IPM-13

KENTUCKY PEPPER

INTEGRATED CROP MANAGEMENT

GROWER MANUAL

Prepared by

Terry Jones; Extension HorticulturistRic Bessin; Extension Entomologist

John Strang; Extension HorticulturistBrent Rowell; Extension Vegetable Specialist

Dave Spalding; Extension Associate

January, 2000

TABLE OF CONTENTS

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Field Selection and Crop Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Soil Preparation and Fertilization . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Cover Crops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Field Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Transplants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Transplanting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

IRRIGATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Drip Irrigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

SPRAYING EQUIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Nozzles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

WEED MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Herbicides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Cultivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Sanitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 INSECT MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

European corn borer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Beet armyworm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Aphids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

DISEASE MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Diseases and Control Strategies . . . . . . . . . . . . . . . . . . . . . . . . . . 19Anthracnose, Cercospora Leaf Spot, & Alternaria Fruit Rot . . . 19Bacterial Soft Rot of Fruit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Bacterial Leaf Spot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Sclerotinia Stem Blight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Phytophthora Blight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Southern Stem Blight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Tomato Spotted Wilt & Impatiens Necrotic Spot Viruses . . . . . 23

Pepper Virus Complex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Nematodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

PHYSIOLOGICAL PROBLEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Flower Drop and Abortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Blossom End Rot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Sunscald . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

COMMON PEPPER NUTRIENT DEFICIENCIES . . . . . . . . . . . . . . . . . . . . . . . 27

SCOUTING AND SPRAY PROGRAM RATIONAL . . . . . . . . . . . . . . . . . . . . . 27

HARVESTING GRADING AND PACKING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Fresh Market Pepper Harvest . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Processing Market Pepper Harvest . . . . . . . . . . . . . . . . . . . . . . . . 29Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

BELL PEPPER PRODUCTION SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 PICTURE SHEETS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

APPENDICESPepper Integrated Pest Management Scout Form . . . . . . . . . . . . 36

Activities by Month . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Predicting Corn Borer Development . . . . . . . . . . . . . . . . . . . . . . . 38

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INTRODUCTION

Peppers are grown in Kentucky for boththe fresh and processing markets. Bellpeppers are one of the leading vegetablecrops grown in Kentucky in terms of totalacreage and dollar returns. Yields of 15tons or greater per acre (1,000-30 poundboxes) of bell peppers have been achievedwith good production practices andfavorable weather conditions. A dailyaverage temperature near 75EF is ideal forpepper growth and development. Peppersgrow well in a wide range of soil types butgrow best in light, fertile well drained soil.The following information was prepared tohelp you achieve maximum returns fromyour crop.

Consult Horticulture Crop EnterpriseCost and Return Estimates (ID-99) for freshmarket and processing pepper budgets.

FIELD SELECTION & CROP ROTATIONWell drained, rolling or flat upland soil

is most desirable for peppers. Avoid low,bottom land areas along creek banks whereair drainage may be poor in order to reducefoliar disease problems. Bacterial leaf spotdisease is very serious under conditions ofhigh humidity and warm temperatures.

Light textured soils with a south facingorientation will warm up faster in thespring allowing earlier fruit productionwhen the price is higher. Select fields thatare free of hard pans and excess weed seedaccumulations.

Crop rotations help reduce weedproblems, as well as diseases such asbacterial leaf spot, phytophthora root rotand verticillium wilt (see Table 1). Corn isa good rotational crop for peppers becauseherbicides available for use in corn control

nightshade and field bindweed. Also, cornis not a host for pepper viruses. Alfalfa isalso a good choice for a rotational cropbecause its frequent cutting cycle reducesmany weeds and available herbicideseliminate most other weed problems.Other crops considered to be usefulrotational crops with peppers includegrasses, cereals, cole crops and beans.

Peppers should not follow tobacco,tomatoes, potatoes or eggplant in a rotationsince they are in the same family aspeppers (Solanaceae) and serious diseaseand or insect problems may result. Inaddition, similar herbicides are used intheir production, resulting in similaruncontrolled weeds. If tobacco is grown inthe rotation it should be planted the yearfollowing peppers.

Table 1 . Rotation for Peppers FromVarious Crop Groups

Crop GroupProbability of

Disease overlap

Pepper, Tomato,Tobacco

Very High

Pumpkin, Melon,Cucumber

High

Cabbage, Broccoli,Cauliflower

Medium

Soybean, Alfalfa, Peas Medium

Corn, Wheat, Grasses Very Rare

Avoid fields where herbicide carry-overmay be a problem (Table 2). Manyherbicides like scepter or atrazine are usedin Kentucky soybean and corn fields andcan carryover and cause serious injury topeppers, especially following dry years.

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Growers should also attempt to locatepepper plantings as far away from tobaccoplantings as possible because of the dangerof aphid movement and virus diseasespread from tobacco to peppers.

Table 2. Rotational Restrictions for PeppersFollowing Soybean and Corn Herbicides

Soybean Herbicides (In months)

CanopyClassicCommandDualLexone or SencorLoroxProwlPursuitReflexSaluteScepterSquadronTri-SceptStatus or BlazerTreflanTurbo

18-B*

BNR12*

12*

4*

AH 16*

18*

12*

18*

18*

18*

AHNR**

12*

Corn Herbicides

AAtrex and othersAccentBeconBicepBladexPeakPrincep

SY10***

18*

24*

AH18*

SY * The rotational restrictions are in months afterapplication.** Read label for additional restrictions due to soil pH,application rate, etc.*** 18 months with a soil pH of greater than or equal to6.5.B = A field bioassay is required before planting the crop;

consult label.NR = No rotational requirementAH = After harvest - can be planted in fall or spring

following application.SY = The crop cannot be planted until the second year

after application (cannot be planted the yearfollowing application).

Fields where tobacco or a legume crop

was grown the previous year may alsopresent a problem if the organic matter andcarryover nitrogen level is high. Someexcellent pepper crops have been grown ontobacco fields, but care should be taken toreduce the initial nitrogen application onsuch fields.

Peppers may follow crops such aswheat, soybeans, cabbage, sweet corn,cantaloupes or cucumbers in the rotation.If peppers are to follow crucifers orcucurbits any potential weed problemsshould be noted since these crops often usethe same herbicides as peppers.

S O I L P R E P A R A T I O N A N DFERTILIZATION

Peppers do extremely well followingfescue sod when the sod is plowed at leasta month prior to planting. Pepper rootsystems have an effective rooting depth of12 to 18 inches with one-half the roots inthe top 6 inches. Hard pans, plow pans,compacted soils, high water tables, andtight soils will restrict root developmentand total yield. Excessive tillage tends tocompact the soil. Subsoiling to a depth of16 to 18in. can improve air and waterdrainage and allows for the development ofa more extensive root system. Use aninsecticide in the setter water for cutwormcontrol especially on sod ground or grassysites. A well prepared plant bed free fromclods that may hold weed seeds is veryimportant. Herbicides will be much moreeffective if the soil is moist, well preparedand free of clods.

Soil preparation and fertilization of thepepper crop varies depending on the cropproduction system used. Regardless of thesystem used, the field should be fallplowed if erosion is not a problem orplowed in the spring as early as possible to

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a depth of 8 to 10 inches. Take a soilsample and have it tested for pH,phosphorus, potassium, calcium, andmagnesium. Soil tests can be sent offthrough the local County Extension Officefor analysis.

Potassium and especially phosphorusare likely to accumulate in most Kentuckysoils following several years of heavyapplications for vegetable crops or tobacco.Soil pH influences plant growth andavailability of nutrients in the soil and isoften low in tobacco fields. Have your soiltested the fall prior to planting so that anyneeded lime can be applied and will havetime to react. Calcium has limited mobilityin the soil, so broadcast and incorporateneeded lime to a depth of six inches in thefall if possible, particularly on sod ground.

A pH range of 6.5 to 7.0 is best forpeppers and liming may be required if soilpH falls below 6.0. Soil test results shouldshow at least 1,500 pounds of calcium and100 pounds of magnesium prior totransplanting. If magnesium levels are low(less than 100 lbs/acre) and lime is needed,use dolomitic limestone. If the soil pH issatisfactory but the magnesium level is low,Epsom Salts (MgSO4) or magnesium oxideor some other source of magnesium may beused.

Soils known to be high in residualnitrogen should be avoided to preventpeppers from producing excessive foliageat the expense of fruit. Consider theprevious crop when deciding how muchnitrogen to apply; there will probably besome residual nitrogen following a cropwhich received heavy doses of nitrogenfertilizer during the previous season.Simple, hand-held electronic meters arenow available which growers can use to

quickly determine the nitrate nitrogenstatus of soils and plants. These Cardymeters can be used to determine residualnitrate levels in soils prior to planting aswell as to measure nitrate levels in plantsap in order to assess the efficiency offertigation.

Nitrate is the form of nitrogen which ismost readily available for use by crops.Soils also contain varying amounts ofammonium forms of nitrogen whichbacteria convert to nitrate forms over time.Nitrate ion meters like the Cardy do notmeasure ammonium nitrogen and thereforemay underestimate some of the nitrogenbecoming available to plants during thecourse of the growing season.

For bare ground plantings on soilsknown to be relatively poor, apply 50pounds of nitrogen per acre preplant.Apply one-half at plowing and one-halfjust prior to transplanting and disk into thesoil. On more fertile soils, apply 25 to 30pounds of nitrogen per acre prior totransplanting.

For processing bell pepper productionwhere plastic mulch is not used,sidedressing or banding additionalnitrogen to either side of the plant whenthe first fruit begin setting is essential forgood yields. Apply 30 pounds of nitrogenper acre at the first sidedressing. A secondsidedressing of 30 pounds of nitrogen twoweeks later should also be made. Nitrogenfertilizer placed up against the plant stemcan burn and injure the plant. Cautionshould also be exercised that too much nitrogennot be put on before pepper pods (1-11/2"diameter) have set on the plant or the plantmay grow vegetatively rather than set fruit.Pepper plants must, however, obtainsufficient size and foliage before bloom and

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fruit set in order to prevent sunscald. Fruitset on small plants will stunt plant growthand such plants will fail to develop the sizeneeded to produce a profitable crop.

For fresh market bell pepper productionon most medium-textured soils whereraised beds, plastic mulch and dripirrigation are being used, we recommendthat all of the phosphorus, all thepotassium, and 30 to 50 percent of thenitrogen requirement be applied prior tobedding and laying plastic. The fertigatedportion of the total nitrogen requirementcan be divided into equal amounts(remaining nitrogen requirement dividedby the number of weeks until final harvest)and injected weekly as in Table 3. (basedon 14,500 plants per acre). Growers withvery sandy soils should also considerapplying 50 to 60 percent of theirpotassium requirement in weeklyincrements through the drip system inaddition to nitrogen. For typical nutrientneeds of a pepper crop see Table 4.

COVER CROPSWinter cover crops help protect the soil

from water and wind erosion. Whenincorporated into the soil as "greenmanure," cover crops contribute organicmatter to the soil.

Cover crops help protect the soil fromwater and soil erosion. When incorporatedas green manure crops they contributeorganic matter to the soil. Organic matterimproves soil structure and reducescompaction and crusting. Organic matteralso increases water filtration, decreasesleaching and releases nutrients to theplants. Cover crops should be plowedunder at least one month beforetransplanting the pepper crop.

The planting of cover crops andsubsequent incorporation of the greenmanure into the soil enhances pepperproduction. Pepper growers frequentlyplant wheat, oats, rye or ryegrass as wintercover crops. If these non-nitrogen fixingcover crops are to be incorporated as green

Table 3. Fertigation Recommendations for Bell Peppers.

Totalfertigated Nrequirement*

ActualN/week

(lbs/acre)

Ammoniumnitrate

(lbs/acre/week)

Ammoniumnitrate (lbs./1000 plants/

wk.)

Calciumnitrate (lbs/acre/week)

Calciumnitrate

(lbs/1000plants/wk.)

75 lbs. /acre 6 lbs 4 oz 19 1 lb 5 oz 40 3

100 lbs./acre 8 lbs 5oz 25 1 lb 11oz 54 4 *Fertigation can begin 14 days after transplanting and assumes 50 lbs N/acre was applied preplant and starter fertilizer was used.

Based on a total season N recommendation of 125 lbs actual N/acre with 50 lbs N/acre applied preplant andthe remaining N (125 - 50 = 75 lbs.) divided into equal amounts to be fertigated on a weekly basis (75 lbs ÷ 12weeks = 6 lbs 4 oz N per week). The dose for 1000 plants is based on a plant population of 14,500 plants/acre(i.e., double rows on 6 ft. centers with plants 12 in. apart in the rows). Either the moderate (75 lb) or high (100lb) N rate can be selected below. For seasons extending beyond 12 weeks a maintenance dose of 1 to 1.5 lbsN/week is adequate.

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Table 4. Pounds of The Major NutrientsUsed by a 22,500 lb. Pepper Crop.

N P K

FruitPlant

4595

66

5090

Total 140 12 140

manure, provide them with adequatenitrogen during their growth. Thisincreases the quantity of organic matterproduced and provides a carbon:nitrogen(C:N) ratio less likely to "tie up" orimmobilize nitrogen during decomposition.As a general rule, when non-leguminousorganic matter having a C:N ratioexceeding 30 to 1 is incorporated, asupplemental nitrogen application (usually20 to 30 pounds of nitrogen per acre) priorto incorporation is recommended. Theexact rate required will depend on the C:Nratio, soil type and amount of any residualnitrogen in the soil. Plow green manurecrops under as deep as possible with amoldboard plow at least three weeks priorto transplanting peppers.

Addition of organic matter:

U improves soil structure (helps to reducecompaction and crusting),

U increases water infiltration,

U decreases water and wind erosion,

U increases the soil's ability to resistleaching of many plant nutrients, and

U releases plant nutrients duringdecomposition.

FIELD LAYOUT Good field layout can significantlyreduce harvest labor time. Often more timeis spent carrying peppers out of the fieldthan is spent picking them, especially ifdrive rows are not left to facilitate sprayingand harvest. Lay fields out so that there aredrive rows approximately every 8 rowsand roadways across the field at 150 footintervals. This conserves time in harvestingand loading the fruit onto wagons or trucks(Figure 1). Pickers can start at the middleof each 150 foot long row and work back tothe drive rows.

Figure 1. Field Layout for Hand Harvesting.

Arranging field with cross roads as shownreduces the time required to carry out harvestedpeppers.

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Table 5. Bell Pepper Varieties

VarietyDays tomaturity Comments

Bacterial Leaf Spot Resistant*

Boynton Bell 70-75 Race 1,2,3 resistant; best overall in 1995-97 trials under epidemicleaf spot conditions. Green to red.

Summer Sweet 890 70-75 Race 1,2,3 resistant. Green to red.

Enterprise 70-75 Race 1,2,3 resistant. Green to red. Also acceptable for processing.

Yorktown 70-75 Race 1,2,3 resistant. Green to red.

Aladdin X3R 70-75 Race 1,2,3 resistant. Green to yellow; can be marketed as green.

Lexington 72 Race 1,2,3 resistant. Virus tolerant (TMV, PVY) Green to red. Fruitlarge, dark green. Plant relatively tall.

Wizard X3R 73-75 Race 1,2,3 resistant, TMV. Green to red, blocky; attractive. Not astolerant to bacterial leaf spot as some other varieties.

Phytophthora resistant/tolerant

Paladin 70-75 Not resistant to bacterial leaf spot; high yielding and attractive indisease free trial.

Not Resistant to Bacterial Leaf Spot

North Star 60-65 Medium large fruit. TMV tolerant. Green to red.

Merlin 65-70 Excellent shape. Consistently high yields in diverse environments,large fruit. TMV tolerant. Green to red. Also acceptable forprocessing.

King Arthur 65-70 Very large fruit. Virus tolerant (TMV, PVY, TEV). Green to red.Also acceptable for processing. Fruit appearance variable.

Specialty Bell

Ivory 65-70 Precocious yellow. Medium sized fruit. White to deep yellow.

Early Sunsation 70 For trial; Race 1,2,3 resistant. Maintains firmness in mature stage.Widely grown in the industry. Green to yellow.

Ledoro Very large yellow fruit

Oriole 74 Light orange.

Mandarin 68-72 Dark orange; elongated fruit; excellent color. Susceptible toalternaria.

Valencia 72 Dark orange, very good color, TMV tolerant.

Lilac 68 Lavender to red.

Purple Pepper 60 Dark purple to red; large fruit

Purple Beauty 70 Green to dark purple to red. Large fruit. *Many varieties with resistance to at least 3 races of the pathogen are commercially available; a number of these have beentested for several years by the University of Kentucky. Those recommended have performed well under both epidemic anddisease-free conditions. We recommend that they be used where bacterial leaf spot is a problem. Check with the processingcompany before growing these for processing. See the Disease Control section for more information on management of thisimportant disease. TMV=Tobacco mosaic virus; PVY=Potato virus Y; TEV=Tobacco etch virus.

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TRANSPLANTS Profits are increased by full stands of

stocky, disease-free plants. Plants caneither be homegrown or bought from areliable source. For maximum yields,transplants should never have fruits,flowers, or flower buds beforetransplanting. An ideal transplant is young(8 to 12 inches tall with a stemapproximately 3/8 to 1/4 inch in diameter),does not exhibit rapid vegetative growth,and is slightly hardened at transplantingtime. Rapid growth following transplantinghelps assure a well-established plant beforefruit development. Transplants should beset as soon as possible after removing fromcontainers. If pepper plants are held forseveral days before transplanting, keepthem cool (around 55"- 65"F if possible) anddo not allow the roots to dry out.

A certification label should accompanyall out-of-state grown plants, and should berequested by growers. To be assured ofgood quality plants, growers may want togrow their own or buy plug plants fromreputable greenhouse sources.

Certified PlantsMany pepper plants are grown in

Florida, South Georgia, Alabama andNorth Carolina and shipped north fortransplanting. Transplant producing areashave certification laws and inspectionsystems directed toward producing highquality, disease-free plants. Before buying, observe the following precautions:

U Buy plants carrying a certificationlabel from the state in which grown.Growers should request certified plantswhen they order. Copies of the invoiceshould be kept in case problems arise at

shipment.

U Determine plant producer'sreputation by asking for references fromother growers who have used his/herplants three or more years.

U Accept shipment only if plants are ofthe correct size, variety, count and ingood condition. Observe plants closely tobe sure they have good terminal buds androot systems.

U Accept only pest-free plants thathave a large root system. Generally, thelarger the root system, the greater the yields.

U Observe plants for overheatingsymptoms. It is to the grower’s advantageto buy seed of the desired variety and send itto the plant producer for growing. Thisreduces potential mislabeling of desiredvarieties. Avoid purchasing plants thathave been clipped since this increasesthe chance of disease.

Greenhouse Grown Plants High quality plants are produced

through top management, and manygrowers grow their own plants. Light,temperature, humidity, moisture, fertilizerand the potting mix must be properlymanaged so that disease organisms, insectsand weeds are controlled. Greenhousegrown plants require 6-8 weeks fromseeding to transplant size.

Greenhouse container-grown plants arerecommended for planting with plasticmulch and trickle irrigation. Plants grownin 72-cell trays are considered economicalto grow while of sufficient size to producelarge and vigorous transplants. Seedshould be treated with bleach (Chlorox) by

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the grower to help reduce seedtransmission of bacterial leaf spot (see seedtreatment procedure under "Bacterial Spot"in the Disease Control section inC o m m e r c i a l V e g e t a b l e C r o pRecommendations, ID-36). Bacterial leafspot remains a serious risk to pepperplantings in many parts of the state andgrowers in areas prone to bacterial spotproblems should use resistant varieties.

Advantages realized from locally grown transplants include:

U Plants of the desired variety.

U Plants that are ready for setting duringoptimum soil and weather conditions.

U Plants that produce a uniform stand(higher survival rate), early growth andhigher yield, especially for plug or containergrown plants when compared to bare roottransplants.

U Greater control of diseases and insects.

U Better control of root system size.

U Higher early yields if plants are containergrown.

U Better control of hardened plants forearly, spring planting. Container grownplants resume growth faster than barerootplants.

Size of Transplant ContainerResearch at Kentucky and other

universities has shown that plants grown in2 1/2 to 3-inch containers produce a largerroot system, bloom earlier and have higherearly marketable yields than plants grownin small containers (for fresh market).Growers often use smaller plug plants for

processing pepper production. Returnsfrom higher early yields often offset theadditional cost of plant production. Totalyields may not differ between plants grownin various container sizes. In one Kentuckystudy the gross early return/acre for using1 1/2" plugs was two times that for plugsthat were only 13/16" in diameter.

Greenhouse grown plug plants must behardened off before setting into the field.Plants are moved outside the greenhouse toexpose them to higher light intensities andusually no fertilizer is applied the weekprior to setting.

TRANSPLANTINGPeppers are a warm season crop and

should be planted only after danger offrosts and freezing has passed. For thecentral, north central and eastern parts ofKentucky the average planting date shouldbe May 7 to 15. For the southern and morewestern counties, transplanting can usuallystart around May 5. It is better to delayplanting a few days than to be too earlyand expose plants to prolonged coldtemperatures. Optimum soil temperaturesfor pepper growth are between 65EF and80EF. Peppers grow best if nighttime soiltemperatures average 60EF or higher.Raised plant beds with black plastic mulchwarm up quickly in the spring and enhanceearlier growth.

When setting plants, roots should beplaced three inches to four inches deep. Attransplanting, apply an appropriatefertilizer starter solution. Aftertransplanting (especially within the firsttwo weeks) it is very important that soilmoisture be maintained so that plant rootscan become well established.

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Peppers for ProcessingTobacco transplanters work very well

for conventional bare root, bare groundpepper production. Peppers grown forprocessing are usually transplanted 16inches apart in rows 36 to 42 inches apart.This will require between 9,957 and 11,616plants per acre. If pimento peppers aregrown, space plants 18 to 22 inches apart inrows 40 to 42 inches apart (7,500 plants peracre). Although processing peppers havetraditionally been grown on bare ground inKentucky, several growers in recent yearshave doubled their profits by using higherplant populations, hybrid varieties, blackplastic mulch, and drip irrigation.

Row spacing and plants/acre are shownin Table 6. Optimal plant population/acredepends upon plant growth habit, plantsize at maturity, vigor, soil fertility, andavailability of irrigation. Adequatepopulations for the many different cultivarsrange from 6,000-15,000 plants/acre. Bellpeppers are fairly compact and rowspacing of 36-42 inches with 12-16 inchesbetween plants are common. For otherkinds of peppers which produce largerplants, the population should be decreasedaccordingly.

Given the higher cost of the raisedbed/plasticulture production system,processors have not objected to growersselling a portion of the crop as fresh greens.Yields can be dramatically increased withplastic and drip irrigation, especially in adry season. Growers are advised to checkwith the processing company, however, asthe benefits of mulch and drip irrigationwill not be as great with open-pollinatedvarieties normally supplied by theprocessor. Techniques (including doublerow spacings) for using this system withprocessing peppers are the same as those

described below for fresh market peppers.

Fresh Market Plasticulture PepperProduction

Planting hybrid bell pepper plants on 6to 8 inch raised beds covered with blackplastic mulch using drip irrigation hasresulted in high yields of excellent qualitypeppers for fresh market sales. A bedshaper/plastic layer and a setter that willtransplant through plastic are essential forthis production system. Two rows ofpeppers spaced 15 inches apart are plantedon each bed; plants are spaced 12 inchesapart within each row. The beds areusually six feet from center to center (14,500plants per acre).

Since a portion of the fertilizer will beapplied though the drip irrigation system(fertigation), uniform watering will ensurethat plants receive adequate nutrients.While the consequences of underwatering(and therefore underfertilizing) areobvious, many growers overlook the factthat overwatering will leach nutrients outof the root zone. Growers using trickleirrigation and plastic mulch shouldcarefully monitor soil moisture usinginexpensive tensiometers. Check themdaily. Don't assume that because it hasrained there will be water in the root zoneunder plastic! For more details on how toset up a trickle irrigation system withfertilizer injection, contact your countyExtension agent or irrigation supplyrepresentative.

Excellent weed control is critical whenplant population is increased because ofdifficulty in cultivating between rows andwith "weeds in the row" which requirehand removal. Never allow herbicides tocollect on the black plastic as pepper plantinjury usually results.

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Starter FertilizersResearch has shown that pepper plants

respond to starter fertilizers high inphosphorus if placed around the plantroots at transplanting. Phosphorus isimportant in promoting rapid root growthand early plant development. Starterfertilizers can be purchased in both thegranular and liquid form. Use 3 pounds ofa granular fertilizer such as 10-52-17,12-48-8, 8-52-16 or similar analysis forevery 50 gallons of water and apply about1 cup of solution around each plant whentransplanting. You will need to use about1 gallon of a liquid starter such as 7-14-7 or6-18-6 per 50 gallons of water to get acomparable amount of phosphorus aroundthe plant roots.

You will usually need from 11 to 12 fiftygallon tanks of starter water to transplantan acre (33-36 pounds of granular starterfertilizer).

Table 6. Pepper Plant Population/Acre WithDifferent Row and Plant Spacings.

Row Width(in)

Plant Spacing(in) Plants/Acre

34 12 15,376

34 14 13,188

34 16 11,531

36 12 14,520

36 14 12,445

36 16 10,890

42 12 12,445

42 14 10,667

42 16 9,334

DR* 12 14,520DR = Double Row - Rows 12" apart with plants 12"apart in row with 6 feet between beds on center.

IRRIGATION

A uniform soil moisture supplythroughout the growing season is essentialto produce consistent yields of quality fruit.Irrigation increases pepper yields from 20to 60 percent and eliminates disastrouscrop losses resulting from severe drought.Long dry periods will cause plants to abortflowers and produce small fruit. Droughtinjured plants are usually slow to recover.Moisture stress in peppers also causes fruitdrop, sunscalding and blossom end rot.Soil moisture should be maintainedbetween 65 and 80 percent of field capacity.Soil at 100% field capacity is saturated andtoo wet for prolonged growth of the plants.Use tensiometers to determine when toirrigate. Transplanting, flowering and fruitdevelopment are the most critical stageswhere a lack of water will severely reduceproduction.

DRIP IRRIGATIONDrip irrigation with black plastic mulch

has become essential for profitable pepperproduction. One of the major advantages ofdrip irrigation is its water use efficiency.Vegetables always require some irrigation.Using drip irrigation results in watersavings of 60% compared to sprinklerirrigation. Weeds are also less of a problemsince only the rows are watered and themiddles remain dry. Studies have alsoshown significant yield increases with dripirrigation and plastic mulch whencompared with sprinkler irrigated peppers.The most dramatic yield increases havebeen attained by using drip irrigation,plastic mulch and supplementing nutrientsby injecting fertilizers into the drip system(fertigation).

Drip tubing may be installed on the soilsurface or buried two to three inches deep.

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When used in conjunction with plasticmulch, the tubing is installed at the sametime the plastic mulch is laid. Usually oneline of tubing is installed on each bed. Iftwo rows of peppers are planted on a bedand they are not more than 12 inches apart,then both rows can be watered from thesame drip line. A field with beds spacedfive feet center to center will require 8,712feet of tubing per acre (one tube per bed).The tubing is available in various wallthicknesses ranging from three mils to 25mils. Most growers use thin wall tubing (8-10 mils) and replace it every year. Heavierwall tubing can be rolled up at the end ofthe season and reused; however, take carein removing it from the field and store in ashelter. Labor costs for removing, storing,and reinstalling irrigation tubing are oftenprohibitive.

Excellent results have been achieved byinjecting at least half of the nitrogenthrough the drip system. This allows plantnutrients to be supplied to the field asneeded. This method also eliminates theneed for heavy fertilizer applications earlyin the season which tend to leach beyondthe reach of root systems or cause salttoxicity problems. Only water solubleformulations can be injected through dripsystems. Nitrogen formulations tend to bemore water soluble and consequently, areeasily injected. Nitrogen also tends to leachquicker and needs to be supplementedduring the growing season. Drip systemsshould be thoroughly flushed with freshwater following each fertilizer injection.

Surface water used in a drip irrigationsystem should be well filtered to removeany particulate matter which might plugthe tubing. The water should be tested forminerals which could precipitate and causeplugging problems.

Tensiometers or soil moisture blocks tomeasure soil moisture levels can bepurchased and placed in the soil. Whenusing tensiometers, on silt loam soilsmaintain the soil moisture below 40centibars at the 12 in. depth. Do not applytoo much water, especially beneath blackplastic mulch.

SPRAYING EQUIPMENT

Sprayers are used for applyinginsecticides, fungicides, herbicides andfoliar fertilizers. Basically, there are twotypes of sprayers: boom and air blast. Boomsprayers are most often recommended forpepper growers. Boom sprayers with theaid of drop nozzles provide better coverageof the plant canopy than air blast sprayers.Boom sprayers get their name from thearrangement of the conduit that carries thespray liquid to the nozzles. Booms or longarms on the sprayer extend across a givenwidth to cover a particular swath as thesprayer passes over the field. Eachcomponent is important for efficient andeffective application.

Most materials applied by a sprayer area mixture or suspension. Uniformapplication demands a uniform tank mix.Most boom sprayers have a tank agitator tomaintain uniform mixing of the spraymaterials. The agitation (mixing) may beproduced by jet agitators, volume boosters(sometimes referred to as hydraulicagitators) or mechanical agitators. Thesecan be purchased separately and installedon sprayers. Make sure an agitator is onevery sprayer. Some growers make themistake of not operating the agitator whenmoving from field to field or whenstopping for a few minutes. Always agitate

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continuously when using pesticides thattend to settle out. If pesticides are notuniformly mixed, inadequate controland/or plant injury may result.

PUMPSBefore selecting a pump, factors such as

intended use, cost, service, operatingspeeds, flow rate, pressure and wearshould be considered. For sprayingpeppers, a diaphragm pump isrecommended because of serviceability andpressures required. A typical pump shouldbe able to apply 60-80 gal/acre at 100-150psi.

Factors to consider in selecting theproper pump for a sprayer are:

U Capacity - The pump should be ofproper capacity or size to supply boomoutput and to provide for agitation. Theboom output, depending upon the numberand size of nozzles, plus 20-30 percent forpump wear is recommended. Capacities ofpumps are given in gallons per minute orper hour.

U Pressure - The pump must produce thedesired operating pressure for the sprayingjob to be done. Pressures are indicated aspounds per square inch (psi).

U Resistance to corrosion and wear - Thepump must be able to handle the chemicalspray materials without excessive corrosionor wear. Use care in selecting a pump ifwettable powders are to be used. Thesematerials will enhance pump wear.

NOZZLESNozzle tips are the most neglected and

abused part of the sprayer. Since clogging

can occur when spraying, clean and test thenozzle tips and strainers before eachapplication. When applying chemicals, besure to maintain proper ground speed,operating pressure, spray height, etc. Thiswill ensure adequate placement of therecommended amounts of pesticides to theplant canopy.

Rapid nozzle wear is a commonproblem. Nozzles are made of differenttypes of materials. To reduce the rate ofwear, ceramic or stainless steel nozzlesshould be used. Use a flat fan type nozzleto apply broadcast herbicides. Flat fannozzles produce an elliptical pattern, wherethe edges are light and heavy in the center.These should be spaced on the boom for 30- 40 percent overlap. When it becomesnecessary to band apply herbicides, use aneven fan or flood nozzle. These nozzlesproduce a uniform pattern across the areasprayed. The fan nozzles should beoperated at 20-40 psi. Flood nozzles aredesigned to operate at lower pressures of 5- 15 psi. The capacity of both type nozzlesshould be 15-20 gpa.

When applying insecticides andfungicides, use solid or hollow cone typenozzles. The two patterns that aredeveloped by solid or hollow cone nozzlescan be produced by different tipconfigurations.

Nozzle ArrangementsWhen applying insecticides or

fungicides, you must completely cover bothsides of all leaves with spray material.When pepper plants are small (up to 12inches) one or two nozzles over the top issufficient. Then, as the plant starts to bushor branch, add drop nozzles. This directsspray material from all directions into thepepper canopy. As the plant increases in

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height, add another nozzle for every eightto 10 inches of growth. In all sprayconfigurations, the nozzle tips should beapproximately 6-10 inches from thefoliage.

Properly selected nozzles should be ableto apply 25-125 gallons per acre operatingat 90-200 psi. Actual capacity and pressurerequired will vary depending on the crop'sstage of development. In most cases, morethan one size nozzle will be needed to carryout a season spray program. Generally,ground speed should be between 2-4 milesper hour. Calibrate pepper sprayers often.Calibration should be conducted every eight to10 hours of operation to ensure proper pesticideapplication.

WEED MANAGEMENT

Weeds reduce pepper yields bycompeting for light, water, and nutrients;delaying maturity; and by reducing harvestefficiency. Peppers are a warm season cropthat need a long growing season, but theyare very poor competitors with weeds earlyin the season. Weeds interfere with harvestand produce seeds that are troublesome inrotational crops. Effective weedmanagement in peppers begins with properfield selection and identification ofpotential weed problems. It involvescultivation, proper land preparation,sanitation, and proper selection ofherbicides. When combined with goodcultural practices, available herbicides cancontrol many of the weed species found inpepper fields. Herbicide choice dependsupon the weed species present and thecultural practices followed by the grower.

Many major weed problems can bereduced by avoiding fields that are

severely infested with weeds such asnightshade, field bindweed, nutsedge, andpigweed which compete effectively withpeppers. Avoid moving weed seed intofields on equipment. When equipment hasbeen used in a weedy field, clean it beforeentering other fields. Deep plowing (9 to 10inches) with a moldboard plow beforedisking and bed preparation can burynutsedge tubers deep enough to preventtheir emergence.

HERBICIDESPreemergence herbicides are applied tothe soil before weeds emerge. They areeffective against germinating weed seedsand usually give residual control. Applypreemergent herbicides just beforeplanting. Some are mechanicallyincorporated into the soil. If weeds havealready emerged, a postemergent treatmentmay also be necessary. Preemergentherbicides are effective against germinatingseeds, not dry seeds. Do not apply thesematerials to wet soils, however, ascompaction can occur.

Postemergence herbicides are sprayedonto the foliage of the weeds after theyhave emerged. They are absorbed by theweeds and translocated to the site of action;thus they work best when sprayed onunstressed plants. Herbicides work best ifthey are applied when soil moisture isadequate for plant growth.

In pepper production, many growersapply glyphosate (Roundup) or paraquat(Gramoxone Extra) between the plasticrows after weed seedlings emerge.Preemergent herbicides may also be tankmixed with glyphosate or paraquat afterweed emergence to provide control ofweed seeds that may germinate latter.

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Cultural practicesThe use of black plastic mulch inhibits

weed growth on pepper beds. However,weeds will emerge at the base of thepepper plant where it is inserted into theplastic. These must be removed by handearly in the season.

If black plastic mulch is used be sure tocontrol weeds that grow between theplastic strips. Tilling between the strips isdifficult because of plastic tearing.

Herbicide useIf fields are infested with perennial

weeds such as Johnsongrass orBermudagrass, they should be treated withRoundup the year before planting toreduce weed problems during the peppergrowing season. Roundup is very effectivein killing the roots of these perennial weedsand does not result in residual carry-over,but it will not control weeds from seed. Allherbicides should be applied at the timesand rates given on the label. Some may beapplied before setting while others must beapplied after setting. Chemicals that can beapplied before planting are usuallyeffective in controlling grasses and a fewbroadleaf weeds, but they do not give totalseason control of Johnsongrass,bermudagrass, barnyardgrass, ragweed,lambsquarters, nutsedge or morningglories.

Annual grasses are usually controlled inpeppers by preplant or post-plantpreemergent herbicides incorporated 2"-3"deep. Barnyard and crabgrass may becomea problem after an incorporated herbicidehas lost its effectiveness. Laybyapplications where annual grasses areprevalent are effective.

Herbicides are no more effective thanthe techniques used to apply them. Sprayer

calibration is of prime importance whenapplying materials at uniform rates. It isextremely important that efforts be made toapply herbicides at uniform rates over theentire area to be treated. This includesusing identical nozzle tips, good agitation,correct pressure and speed. Post-emergentherbicides may require a surfactant.

Rainfall or irrigation within 4-5 days ofherbicide application is necessary for somechemicals to be effective.

There are no foliar-applied herbicidesthat selectively control broadleaf weeds inpeppers; however, sethoxydim (Poast) canbe applied to control most annual andperennial grasses during the season. Poasthas good selectivity on peppers, but maycause some phytotoxic symptoms if thetemperatures are above 85° to 90°F. ForPoast to work well, the grass should begrowing vigorously. Napropamide(Devrinol) can be applied over the top oftransplants immediately before a rain orsprinkler irrigated into the soil.Metalachlor (Dual) may be applied prior tosetting or up to 48 hrs after setting peppers.Both clomazone (Command) andtrifluralin (Treflan) are applied andincorporated before transplanting

Where black plastic mulch is used, Dualand shielded Gramoxone Extra sprays haveworked well between the beds for weedcontrol.

On bare ground plantings the bestpreemergence weed control is obtained byapplying two herbicides such as Treflanand Command, Treflan and Dual, orTreflan and Devrinol. This provides abroader spectrum of weed control.

For weed control recommendations,

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refer to the current issue of ID-36C o m m e r c i a l V e g e t a b l e C r o pRecommendations, available through yourlocal county Extension office.

MONITORINGTo plan a weed management program,

it is essential to know which weed speciesare present and the relative abundance ofeach. Conduct weed surveys of each field atleast twice a year: the first after plantingbut before weeding and the second justbefore harvest. Records from previouscrops will indicate what weeds escapedcontrol and will likely infest the peppercrop. Also examine fence rows and ditchbanks, as these are other sources for weedinvasion. Pay special attention to whereperennial weeds occur so that follow-upcontrol measures can be taken.

Weeds compete for water, fertilizer andsunlight as well as harbor insects anddiseases. They greatly reduce harvestingefficiency thereby increasing costs.

Pigweed, lambsquarters, morning gloryand weeds of the nightshade family causethe most common weed problems inpeppers. Growers should survey theweeds in the field before planting andcheck the Guide to relative response ofweeds to herbicides chart in the front of ID36, Commercial Vegetable CropRecommendations to see if these weeds canbe e f fec t ive ly contro l led wi threcommended herbicides. Remember thatmajor variations in soil type within a fieldmake application of herbicides difficultbecause the rates must be adjusted.Rotation helps prevent difficult weedproblems because the changes in plantingtimes, cultural practices and herbicideshelp eliminate those conditions favoring aparticular weed. Sweet corn is a valuable

rotation crop for peppers because severalherbicides are available for corn that willcontrol morning glory and weeds in thenightshade family. Cucurbits (cucumbers,cantaloupes, etc.) do not provide a goodrotation because they use many of the sameherbicides used with peppers. To plan aweed management program you mustknow what weeds are present. Do notapply granular treflan with your fertilizeras this often leads to uneven distributionand very poor weed control.

CULTIVATIONHerbicides seldom provide complete

control of all weeds when applied, so somecultivation and hand hoeing is needed inmost pepper crops. Remember the oldsaying, "one years seeding results in sevenyears weeding." Cultivate while weeds aresmall in order to keep cultivation shallow.Cultivation after fruit set (if necessary)should be shallow. Root pruning bycultivation slows plant development,reduces yield and promotes blossom dropand blossom end rot. Even a small stand ofweed seedlings can deplete the soilmoisture in the upper soil layer.

SANITATION Rogue out or spot treat small

infestations of troublesome perennials.Clean fence rows to prevent weed spreadinto the field. Glyphosate and gramoxoneherbicides are valuable tools in eliminatingemerged weed seedlings and perennialweed problems.

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INSECT MANAGEMENT

Pepper production in Kentucky isplagued by moderate levels of insect pests.This includes European corn borer and beetarmyworm that attack the fruit (directpests) as well as insects attacking thefoliage such as aphids and flea beetles(indirect pests). Occasionally, cornearworms and yellowstriped armywormcan attack pepper fruits, but this is lesscommon. However, as with most insectsencountered in the Midwest, populations ofindividual pests vary from year to year andlocation to location reinforcing the need toroutinely monitor pepper fields.

EUROPEAN CORN BOREREuropean corn borer can cause severe

damage to peppers in commercial fieldsthroughout Kentucky. Feeding by cornborer larvae can cause several problems,the most serious of which is direct damageto the fruit and premature drop of smallfruit. Borer entrance holes in larger fruitallow water to enter, resulting in fruit rot.When rotting begins, borers often leave andmove to infest new fruit. In this way, onelarva can damage several fruit. In addition,plants may break due to tunneling by theborers in the stems.

European corn borer larvae areflesh-colored with inconspicuous, lightbrown stripes down the body. They areabout l-inch long when full-grown. Adultfemale moths are pale yellow-brown withirregular, wavy, dark bands across thewings. Males are distinctly darker witholive brown markings on the wings. Themoths are good fliers, and are active oncalm nights.

European corn borer moths tend tocongregate in tall grassy areas around fieldmargins, these are called action sites.Females fly into fields at night to lay theireggs. Weather conditions during egg layingcan greatly affect the severity of corn borerproblems. Calm warm nights are mostfavorable for moth activity while few eggsare laid on windy, stormy nights.

European corn borer eggs are laid inmasses of 15 to 30 eggs per mass. Eggs areround and flattened and overlap each otherlike fish scales. Often they are placed on theunderside of the pepper leaf near themidrib. Age of the egg mass is indicated byits color: freshly laid eggs are white, thencream. When a distinct black spot, the headof the larva, can be seen in the egg, it willhatch within 24 hours.

Newly hatched larvae, about 1/16 inchlong, leave the mass and crawl toward thedeveloping fruit. They do little feeding onpepper leaves. Within 2 to 24 hours afterhatch, young larvae reach the calyx of thepepper fruit. Once under the calyx, they areprotected from insecticides and naturalenemies.

There are two to three generations ofthis pest each year. The first appears in lateMay through early June. This firstgeneration does not attack peppers, soproducers do not need to use an insecticideat this time. This generation attacks cornand other weeds. The second generationdevelops from late July through August. Apartial third generation may occur in someyears in early September. The second andthird, or midsummer generations, are mostlikely to cause problems for commercialpepper producers.

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ManagementAbundance of European corn borers

varies from year to year. Inspection ofpepper leaves for corn borer egg massesand young larvae is impractical andineffective. Growers are encouraged to usepheromone traps and/or black light trapsto determine if corn borer moths are activeand when treatments should be applied tocontrol small larvae before they enter thepepper fruit. If corn borers are caught intraps, then begin looking in grassy areasnear your field. If moths are found in theseaction sites and the plants have fruit, thena spray is justified.

European corn borer is difficult tocontrol because of the short intervalbetween egg hatch and larval tunneling ofthe fruit. An insecticide must be appliedbefore larvae have entered the fruit orstems and spray coverage must bethorough. Over reliance on pyrethroidinsecticides (Ambush, Asana, Baythroid,and Pounce) can lead to the rapid buildupof aphids on pepper foliage through thereduction of natural enemies. Whilepyrethoid insecticides can provide effectivecorn borer control, they should be used inrotation with other classes of insecticides toprevent aphid outbreaks.

Try to avoid insecticide sprayapplications during the bloom period toprevent unnecessary bee kills. If treatmentis necessary, then spray in the earlymorning or late evening when bees are notactive. A dry spray deposit is lessdangerous to foraging bees.

Corn Borer ModelA degree day model that predicts the

occurrence of the corn borer life stages isavailable at the University of Kentucky. Itis recommended that these predictions be

used in combination with field scouting ofmoth activity in action sites or pheromonetrapping in order to make managementdecisions. These predictions will alert youto when it is necessary to monitorpheromone traps closely and scout fields.

Current degree day accumulations areavailable for European corn borer, as wellas other insects for many locations in thestate through the Agricultural WeatherCenter maintained by the UK Departmentof Agricultural Engineering. Up-to-dateEuropean corn borer estimates are availablethrough the World Wide Web using thef o l l o w i n g a d d r e s s"http://wwwagwx.ca.uky.edu/." SeeENTFACT 106 for a explanation of how touse the degree day estimates (Appendix 3).

BEET ARMYWORMThe beet armyworm is a major pest in

the southwestern and southern USattacking alfalfa, beans, beets, cole crops,corn, lettuce, onion, peppers, potatoes,peas, and tomatoes. It is an occasionalinvader of vegetable crops in the OhioRiver Valley. Although it cannotoverwinter here, it is a significant pest forvegetable growers because of its wide hostrange and resistance to most insecticides.Producers of fall vegetable crops need towatch out for this pest during August andSeptember. This insect is killed by the firsthard frosts in the fall.

The beet armyworm is a light-green toblack larva with four pairs of abdominalprolegs and a dark head. There are manyfine, white wavy lines along the back and abroader stripe along each side. There isusually a distinctive dark spot on each sidejust above the second pair of true legs.Female moths lay masses of up to 80 eggsunderneath a covering of cottony-white

18

scales, as many as 600 eggs over a 3 to7-day period. These eggs hatch in 2 to 3days and the larvae first feed together in agroup near the egg cluster. As they grow,they gradually move away from the eggmasses. Many small larvae die during thiswandering stage and the behavior tends tospread out the infestation. Beet armywormis quite mobile, one larvae may attackseveral plants in a row. Older larvae mayfeed on fruit as well as leaves. After theycomplete their feeding, the 1-1/4" inchlarvae pupate in the soil in a loose cocooncontaining soil particles and leaf fragments.The life cycle takes about a month tocomplete.

Beet armyworm feeding on youngtender growth can be very damaging tosmall transplants. Often a fine webbing isproduced by smaller larvae near thesefeeding sites. Older plants can becomerapidly defoliated. Vegetable growersshould pay particular attention to fallplantings of beans, tomatoes, crucifers,other truck crops.

ManagementRegular scouting of fields to detect the

first indications of a beet armyworminfestation is critical. Growers in Kentuckyand southern Indiana should scout theirfields weekly and watch for small beetarmyworm larvae feeding in groups onyoung leaves. If beet armyworm larvae arefound, a spray is justified. Sprayscontaining Bacillus thuringiensis var azawaiare effective when used at higher labeledrates against young larvae.

Beet armyworm has few effectiveparasites or predators which can effectivelyreduce its numbers. Broad-spectruminsecticides are needed when large numberof larvae are present. If a complex of insect

pests including beet armyworm arepresent, treat them as beet armywormwhen selecting an insecticide. SpinTor(spinosad) is a new class of chemistry thatcan provide high levels of control of beetarmyworm. Cyfluthrin (Baythroid) andmethomyl (Lannate) are also recommendedfor beet armyworm control, but theyprovide only moderate control, at best, ofsevere infestations.

Timing of insecticide applications isvery important. Once larvae are 1/2 inch orlonger, they become very difficult to killwith insecticides. So treatment must betargeted against young larvae. Only withfrequent field surveys can these pests bedetected and controlled effectively.Coverage is also an importantconsideration. Because insecticides canprovide only moderate levels of control, itis important to deliver the proper dose tothe pest. Drop nozzles, high pressure (200psi), hollow cone nozzles, reducing sprayerspeed (2 to 2.5 mph), and a high volumespray will allow for thorough coverage ofthese vegetable crops.

APHIDSSeveral aphids species may be

commonly found infesting peppers duringmost of the growing season. The mostcommon aphid on peppers is the greenpeach aphid. Large numbers of aphids canaffect pepper production in two ways.Honeydew produced by aphids can leavea sticky film on the surface of the fruit andcause the development of sooty mold fungi.Various species of aphids can also transmitviruses, notably potato virus Y, that canreduce yields. Aphid infestations maybegin in the greenhouse on peppertransplants.

As aphid colonies begin to form on the

19

leaves, development occurs rapidly.Aphids reproduce without mating andindividual generations may be completedwithin one week during the summer.Winged adult aphids develop periodicallyand disperse from fields following periodsof overcrowding. Colonies are found on theundersides of leaves, usually in the lowercanopy.

ManagementSome insecticides used for other pepper

insect pests can contribute to rapidincreases of aphids. Natural enemies suchas lady beetles, green lacewings, anddamsel bugs usually control aphidpopulations adequately. Broad spectruminsecticides, particularly pyrethroidinsecticides, can deplete these naturalenemies and allow aphid populations todevelop unchecked. Insecticides shouldonly be applied for other insects whennecessary, as determined by trap catchesand scouting, and care should be taken toselect insecticides that do not favorsecondary aphid problems.

DISEASE MANAGEMENT

DISEASES & CONTROL STRATEGIESIn the early 1980's Kentucky produced

over 8,000 acres of bell peppers each yearfor 5 processing companies and severalfresh market cooperatives but due tobacterial leaf spot, the acreage declineddramatically. Consequently bacterial leafspot is considered to be the most seriousdisease in pepper production in Kentuckyand surrounding states (Table 7). Todaythere is one bell pepper processorcontracting in Kentucky and fresh marketbell pepper acreage, through the use of leafspot resistant cultivars, is just beginning torecover.

Table 7. Importance of Pepper Diseases ByState

Disease KY OH IN TN

Anthracnose 3 2 - 2

Bacterial spot 1 1 1 1

Phytophthora 5 2 2 4

S. rolfsii 6 - - 3

Cercospora 7 - - 7

Poty-viruses 2 - - 6

TSWV 4 4 3 5- = not important# ranked, 1 = most serious problem

ANTHRACNOSE, CERCOSPORA LEAFSPOT, AND ALTERNARIA FRUIT ROT

Anthracnose occurs as sunken spots onripe fruit, accompanied by pinkish sporemasses during wet conditions; infectionoccurs on both green and ripe fruit.Anthracnose and Alternaria Fruit Rotfrequently develop on injured or over-ripefruit. Protecting fruit from the effects ofbacterial leaf spot and sunscald andharvesting carefully will reduce problemsfrom these fruit diseases. Cercospora leafspot develops as large circular to oblongspots usually with a white to gray centerduring prolonged periods of hot, wetweather. Alternaria develops as a blackmass of spores on damaged areas of thefruits. Use disease-free seed and ortransplants. Rotate for 3 to 4 years to cropsnot related to pepper (see Table 1),controlling solanaceous weeds during therotation. Plow down crop residuesimmediately after harvest. Weeklyfungicide sprays with Maneb 80 at 1.5 to3.0 lbs/A are effective if sprays start priorto or at the time when first symptomsappear and are maintained past bloom tocontrol anthracnose and the fruit phases ofthese diseases. Copper fungicides are alsolabeled, but have limited value on thesediseases . For more complete

20

recommendations, see ID-36 CommercialVegetable Crop Recommendationsavailable at your County Extension Office.

BACTERIAL SOFT ROT OF FRUITBacterial soft rot causes a very soft

slimy rot with a strong odor. The bacteriacausing it are commonly present on thefruit surface and enter the fruit throughwounds, especially those caused byEuropean corn bores. Control insect pests(especially corn borers) and spottingdiseases to minimize wounding. If washwater is used in packing operations, itshould contain 25 ppm of availablechlorine. A number of chlorine sources areavailable, but for most small operations inKentucky the most available option is touse household bleach (those containing5.25% sodium hypochlorite) at the rate of 1tablespoon of bleach per 8 gallons of wateror 1 pt/264 gallons of water. To keep thechlorine available, it is important that theinitial water pH be 6.0 to 7.5, that the waterremain clean and is changed often, and thatthe water is near the temperature of thefruit (no colder than 10EF below that of theharvested fruit). If the wash water is toocold, the wash water will be pulled into thefruit and promote disease development.

BACTERIAL LEAF SPOTBacterial leaf spot occurs as

water-soaked, black to tan, irregularshaped spots on the leaf (see figures),especially the margins, and on fruits asraised spots. Defoliation of infected leavescan be extensive, greatly impacting fruitquality. This disease can be a limitingfactor in pepper production in Kentuckyand chemical controls have been marginalunder strong disease pressure. Fortunately,major improvements in control optionshave recently become available in the formof resistant varieties. Bacterial Leaf Spotcan result in severe damage to pepper

crops. It has been one of the most seriousand costly problems affecting peppers inKentucky, causing thousands of dollarsworth of damage. The successful growermust understand and appreciate thisdisease's potential, to successfully growpeppers. Bacterial leaf spot is favored bywarm, wet weather and its spread is aidedby driving rain or wind-blown soil anddebris.

U Use Resistant Varieties: Based on studiesdone in Kentucky, resistant varieties shouldbe used for both fresh market andprocessing where possible. See the peppervariety table (Table 5.) for a listing ofseveral recommended resistant cultivars.Other control options will continue to berecommended because susceptible peppervarieties will continue to be released .These control options are also necessary tomanage strains of the bacterium that maynot be controlled by resistant varieties.

U Seed-borne Disease: The bacteriumcausing this disease is seed-borne,transplant-borne, and over winters on siteand nearby in weeds such as nightshade,horse nettle and ground cherry andresidues. Bacterial leaf spot remains viableon plant residues as long as there is anyresidue left. The bacteria may survive aslatent epiphytes (living without causing aninfection) on the leaves of "healthy" plants.Once it is introduced into the planting andunder prolonged wet conditions, control islimited because of the rapid rate ofreproduction and limitation of availablechemicals. Therefore, control is centeredaround preventing introduction of thebacterium rather than eradication of itonce present!

U Use crop rotations of 2 to 3 years,excluding peppers, eggplant, tomatoes, andtobacco from the total rotation, also

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excluding small grains in the rotation theseason before peppers are to be planted.Control broadleaf weeds during therotation and around the field borders. Diskall crop residues into the soil promptlyafter harvest to encourage more rapiddecline of the bacterium and plow covercrops very early in the spring to minimizecarry-over.

U Do not work plantings while wet.Spraying plants while wet with highpressure may encourage spread by blowingbacteria about the field.

U Use Disease-free seed and transplants:Plant disease-free seed whenever possibleand treat them before planting withhousehold bleach (2 pts household bleachto 1 gallon of water per lb of seed, washingfor 40 minutes with continuous agitation).Air dry, dust seed with Thiram 65 W at 1tsp/lb of seed, and sow promptly to controldamping off. While in the seedbeds andstarting with the first true leaf stage, makefrequent applications (3 to 5 days) of theantibiotic Streptomycin 17% at 200 ppm or2 teaspoons/ gallon of water. (Note:streptomycin is labeled only for use prior totransplanting and is not labeled for use in thefield and should not be used in the field.) Also,note that streptomycin is not specificallylabeled for greenhouse use, so use fixedcoppers in greenhouse transplantproduction, but do not expect the highdegree of control available withstreptomycin.

U If transplants are purchased from offthe farm, obtain only certified disease-freetransplants and assume that you probablyhave still purchased some low level ofinfection. Plant them into soil withrecommended rates of N and K, but at thehigh end of the scale. Losses from bacterialspot are greatest when peppers become

deficient in N or K and the disease can beminimized by maintaining high fertility,being careful not to get the plants into anoverly vegetative state or fruit set will beseriously reduced.

U Foliar Sprays: Sprays made early in theseason before symptoms are evident are themost valuable at keeping population of thebacteria low. Start sprays immediately aftertransplanting with fixed copper ( 1.0 lb ofactive ingredient) plus Maneb 80 at 1.5lbs/A and continue at 7-day intervalsduring wet weather to reduce buildup andspread of the bacterium in the field (seelabels for rates). After mixing Maneb andfixed copper in the spray tank, let it sit for 30minutes with agitation. During this period anew chemical compound will be formed that ismore effective at controlling bacterial spot thaneither of the two individual materials. Notethe copper material can be applied morefrequently, but maneb is labeled for nocloser than 7-day intervals, plus note thatmaneb has a 7-day preharvest intervalwhile coppers have zero.

22

Table 8. Bacterial Leaf Spot - Coppers &Maneb

Material

Rate ofMaterialto Use/A

Minimum Days To:

Harvest Reentry

Copper(Kocide 101)

2.5 lb 0 2

Kocide DF 2.5 lb 0 2

Copper-Count N

3 qt 0 2

Kocide 606 2 qt 0 2

ChampFlowable

2 qt 0 2

basiccoppersulfate

3 lb 0 1

maneb 4F 2.5 pt 7 1

maneb 80WP

1.5 lb 7 1

maneb 75DF

1.5 lb 7 1

SCLEROTINIA STEM BLIGHTSclerotinia Stem Blight is caused by a

fungus living in the soil and attacking thebase of the pepper plants. The disease isfavored when organic matter plowedunder is not completely broken downbefore planting. Sclerotinia is characterizedby white cottony growth on the stem andsmall hard black seed like structures(sclerotia) which form in the pepper stems.Good site selection and good fieldpreparation will help control this disease.Crop rotation must also be used.

PHYTOPHTHORA BLIGHTPathogens: Phytophthora capsici, P. parasiticaThis disease can cause serious losses, butfor some reason has caused limitedproblems in Kentucky. This could rapidly

change with changes in production,especially water management.

Symptoms:Above ground symptoms of

Phytophthora root and crown rot includerapid wilting and death of affected pepperplants. Phytophthora blight occurs as arapid wilting and death of plants,especially in wet areas of the field. Fruitrot occurs as a water-soaked, dark rotusually surrounded by a halo of lightercolor. Close examination of the roots andstems of affected plants is necessary toconfirm the cause of disease. The diseasecan develop at any plant growth stage. Taproots and smaller lateral roots show watersoaked, very dark brown discoloration.Stem lesions are first dark green andwatersoaked, then dry and turn brown.Factors that influence the development ofroot and crown rot in peppers in a givenseason include varietal susceptibility,amount and frequency of irrigation, andsoil compaction and drainage. The fungussurvives in the soil for several years and issimilar to tobacco black shank. The blackshank fungus can also cause a fruit rot ofpeppers.

Cultural Control:The disease can be effectively prevented

by a program integrating crop rotations of2 years that exclude susceptible plants,irrigation management, and clean seed andtransplants. In heavy soils that are poorlydrained, root and crown rot may bereduced by carefully managed dripirrigation. Practices that reduce or alleviatesoil compaction may improve control; forexample, growing plants on raised beds.One variety is available which hasperformed well in Kentucky trials and hasresistance to Phytophthora (but which isnot resistant to bacterial leaf spot--Seecultivar Table 5.

23

Chemical Control: Fungicides are sometimes used in fieldswith histories of root rot or problems withdrainage. Soil drainage is critical tocontrol; avoid wet fields, and plant onraised beds in well drained soils. Rotate tonon-solanaceous crops and non-cucurbitcrops for 3 to 4 years to reduce diseasepotential. If planting into fields with ahistory of disease, make a preplantincorporated application of Ridomil GoldEC at 1 pt/A before transplanting, plusadditional applications at 30 and 60 daysafter transplanting, directing the spray as aband on either side of the plant. Thecopper/maneb sprays used for bacterialspot control should also reducePhytophthora fruit infections, but will notcontrol the root and stem phases of thisdisease. Ridomil Gold/Copper 70W at 2.5lbs/A as a foliar spray at 10-14 dayintervals is also an option for preventingthe stem and fruit phases.

SOUTHERN STEM BLIGHT Sclerotium rolfsii

This disease can be a problem whererotation includes soybeans, tomatoes orother susceptible crops. The fungus attacksthe stem near or at the soil line and formswhite mold on the stem. Later small roundbrown bodies (sclerotia) appear in themold. Infected plants wilt and die slowly.This disease is often found in lots oftransplants, so set clean plants. Avoid fieldswith a history of this disease and rotateproblem fields with sod crops. Sclerotiumrolfsii has a wide host range and is commonin Kentucky on tobacco, soybeans, peppers,and tomatoes. Deep plow to bury sclerotiaand crop debris. Incorporate cover cropsearly to ensure they are well rotted beforetransplanting into the site. Maintain goodweed and grass control through preventivemeans because the fungus can attack dyingweeds then move onto pepper transplants.

The fungicide PCNB (Terrachlor 75 WP) at3 to 5 lbs/ 100 gallons in the transplantwater is an aid to control, but better resultsare obtained if the material is sprayed intothe transplant furrow using 10 lbs/ 100gallons over 14,500 ft of row. It is importantto maintain agitation [see label].

TOMATO SPOTTED WILT ANDIMPATIENS NECROTIC SPOT VIRUSES

These viruses are carried by thrips andcan cause serious losses in transplantproduction or when introduced in thetransplants. Ensure that transplants arefrom fields or greenhouses certified to befree of TSWV. Local transplant producersshould take steps to reduce the spread ofTSWV and INSV by followingrecommended thrip control and notproducing pepper transplants in houseswhere ornamentals are being produced orsold. Rogue out infected plants as soon asthey are found and maintain a thrip controlprogram. Avoid using transplants fromsources containing these viruses.

PEPPER VIRUS COMPLEX This is the name given to several virus

diseases that attack peppers in Kentucky.Viruses are the second most importantdisease problem (Table 7) on Kentuckypeppers because of the production oftobacco. At least four viruses areresponsible, tobacco mosaic (TMV), tobaccoetch virus (TEV), cucumber mosaic virus(CMV) and potato virus (PVY). All exceptTMV are transmitted primarily by aphids.On occasion, tomato spotted wilt virus(TSWV) which is transmitted by the adultthrip has been found. Aphids carry theseviruses to pepper fields from perennialweeds growing nearby. Plants infectedearly in their life may be stunted, havedeformed leaves with mosaic or mottlingpatterns, and produce small, discolored,misshaped fruit (see figures). Plants

24

infected later in the season are not as badlystunted. Pepper viruses may also causeflower drop in pepper which alsocontributes to lower yields.

Pepper Virus Complex Control:1) Plant peppers in and surrounded by fieldsused for row crops "barrier crops". Six rows ofcorn around a pepper planting will reducevirus transmission to the peppers by 80%and delay the time of aphid infection anddevelopment. Peppers planted near woods,fence rows, hay, or pastures may beexposed to virus-carrying aphids fromnearby weedy perennial hosts. Partialisolation from infected aphids can beaccomplished by locating fields betweenplantings of corn or other non-host, fieldcrops where the weeds are killed beforepeppers are transplanted. Do not growpeppers within 150 ft of virus susceptibletobacco. Controlling aphids in tobaccolocated near peppers, especially at thetimes of tobacco topping and harvest, mayhelp to reduce movement of aphids andviruses to peppers.

2) Plant peppers as early as possible. Virusdiseases normally show up in earlysummer. Since aphids feeding for only ashort time will introduce viruses into theplant, aphid controls are not effective.

3) Control weeds, especially those in thenightshade family, in and around the pepperfields.

4) Use virus resistant pepper and tobaccocultivars (Table 9) whenever possible.Observations from recent surveys indicatethat growing tobacco varieties resistant tothe aphid-borne virus complex may behelpful in reducing these diseases inpeppers, probably because the pathogenlevel in the nearby plant community isgreatly reduced.

5) Maintain aphid control in peppers. Inproblem fields, with a high value freshmarket crop, spraying weekly with styletoils can be helpful (using 3 qt/100 gallons)[see labels and follow the labeled protocolstrictly], but the value of this treatment hasnot been evaluated in Kentucky. Reflectivemulches show promise in reducing theincidence or delaying the onset of thesediseases in some tests.

NEMATODESRoot knot nematodes, Meloidogyne

incognita, M. hapla, and M. arenaria causeeconomic damage to peppers whenpresent. They are usually a problem insandy soils such as those in a river bottom.Nematodes cause physical damage to rootsystems and open up wounds that allowdisease to become established. Nematodeinfested plants are generally stunted withpale green to light yellow foliage. Soilsinfested with root knot nematodes shouldeither be treated with chemicals(fumigated) or avoided.

25

Table 9. 1999 Burley Tobacco Varieties: Disease Resistance, Relative Yield Scores, and Maturity

Variety Black Shank VirusComplex

Black RootRot

TMV Fusarium RelativeYield Score1

Maturity

Race 0 Race 1

ms KY 14 x L8 10 0 S M R M 7 early

KY 8959 1 1 R H S - 7 late

KY 907 2 2 R H R - 8 med-late

KY 908 4 4 R H R - 2 med-early

KY 910 10* 5* R H R - 2* med-early

NC BH 129 1 1 S H R S 7 med-early

NC 2** 2 2 R H R S 3 medium

NC 3** 2 2 R H R S 7 med-late

TN 86 4 4 R H S S 7 late

TN 90 4 4 R H R - 6 med-late

TN 97 5* 5* R H R - 7* med-late

Hybrid 403 0 0 S M R M 9 medium

N-126 0 0 S M R - 7 medium

NBH 98 2* 2* S M* R - 4* medium

R 610 4 4 S M - - 5 medium

1 = Relative yield scores are based on growth under disease free conditions.* = Based on a limited number of field tests and subject to change.** Resistant to root knot nematode (Meloidogyne incognita, Races 1 and 3).- Resistance not rated for this disease.

PHYSIOLOGICAL PROBLEMS

FLOWER DROP AND ABORTIONFlower drop is an indication of pepper

plant stress at the time of flowering. Thismay be a response to temperature stress(greater than 90EF or less than 50EF), waterstress, root pruning (cultivation), shadingor excess fruit load. Stink bug and pepperviruses will also cause flower drop. Peppercultivars differ greatly in their ability towithstand stress.

FRUIT SETVery little fruit set occurs when

temperatures are above 90EF during theday or below 60EF at night. Fruit that set attemperatures above 85EF are usually smalland deformed. Best fruit set occurs whentemperatures are between 65EF and 80EF.In general hybrid pepper cultivars havebetter tolerance to heat stress than open-pollinated cultivars.

BLOSSOM END ROT Blossom end rot (BER) usually occurson fruit 1/3 to 2/3 mature size as a smallwater soaked spot at or near the blossomend (bottom of the pepper.) The watersoaked spot enlarges and becomes dry,sunken, flattened, brown or black andpapery or leathery.

26

BER is caused by inadequate calciumavailability in the fruit tissues duringperiods of rapid growth. The lack ofadequate calcium can be due to low levelsin soil, but is most often caused by poorcalcium uptake and movement associatedwith uneven soil moisture and/or plantroot damage. Excessive levels of potassium(K+) and the over use of ammoniumfertilizers may aggravate this problem. Themost effective control is to maintainuniform soil moisture conditionsthroughout the growing season and notdamage roots during cultivation orfertilization. Be especially careful of soilmoisture conditions when using raisedbeds which can dry more quickly. Foliarcalcium sprays are not considered an effectivetreatment, but proper soil calcium levels shouldbe maintained.

B E R Control (Prevention)

U Grow pepper crop on well drained soils,avoid water logged fields. Plant on raised bedsto ensure good drainage.

U Apply fertilizer according to soil test.Maintain adequate calcium and avoid excessiveammonium nitrogen applications, highlysoluble (K) potassium, (Mg) magnesium or(Na) sodium salts.

U Cultivate shallowly especially after fruit setor in dry weather.

U Maintain uniform soil moisture throughoutthe growing season, especially as fruit develops.Use plastic mulch and trickle irrigation to helpreduce moisture fluctuations on peppers forfresh market.

SUNSCALD Sunscald is a noninfectious problem

caused by exposure of pepper fruit to directsunlight and high temperatures. This is a

common problem on plants havingpremature foliage loss (usually fromdisease, cultivation damage, or hail).Nitrogen deficiency after fruit set delaysplant canopy development and increasessunscald problems. Plants which grewpoorly when small and then set fruit arevery prone to sunscald. Symptoms includean irregular light colored scalded areawhich appears on any fruit surface directlyexposed to the sun. Affected areas becomesunken, wrinkled and creamy white as fruitages. Sunscald areas dry out and becomepaper thin.

Sunscald Control (Prevention)

U Select pepper cultivars which developadequate foliage cover.

U Control diseases and insects.

U Provided adequate nutrient levels(fertilizer, water).

U Use good cultural practices to reduce theincidence of sunscald, (proper plant spacing,double rows, black plastic, irrigation). Somegrowers will stake and tie plants to preventthem from falling over in storms andsunscalding the fruit.

COMMON PEPPER NUTRIENTDEFICIENCIES

LOW SOIL pHIf the soil pH is too low a number of

nutrients can be limiting or present at toxiclevels. Under these conditions plants maybe stunted and yellowish white in colordue to manganese and aluminum toxicity.

NITROGENNitrogen deficient pepper plants are

pale green or yellowish. The plants will

27

tend to be stunted. Older leaves willgradually die and drop from the plant asnitrogen is removed from these and movedto the young leaves.

POTASSIUMDeficient plants show yellowing of leaf

margins which rapidly die leaving leaveswith brown dead edges. A lack ofpotassium affects the oldest leaves first andthe upper part of the plant may be normalin appearance.

PHOSPHORUSThe leaves on phosphorus deficient

plants are small and dark green.Phosphorus deficiency is more commonearly in the season when soils are cold andphosphorus is not readily taken up.

MAGNESIUMMagnesium deficiency is common on

pepper plants. Yellowing of the leaves isapparent in the interveinal areas and veinsremain green. The oldest leaves areaffected first. Sometimes magnesiumdeficiency occurs when excessiveapplications of potassium have been made.It may also show up under extremely hotdry weather.

Apply magnesium as dolomitic lime ifthe pH is low or as magnesium oxide whendolomitic lime is not available or a soil pHchange is not needed.

SCOUTING AND SPRAY PROGRAM RATIONAL

It is strongly recommended thatgrowers plant bacterial leaf spot resistantvarieties, particularly if there is a history ofthis disease in the area. Even though thesevarieties are resistant to the three strains ofthis disease that are most common in

Kentucky, it is important to keep up aspray program to discourage thedevelopment of other strains, there are 10in total now nationwide, of bacterial leafspot. If other strains become widelyestablished in the state, the resistantvarieties will no longer be useful.

As soon as the pepper plants aretransplanted to the field, apply two spraysof fixed copper and Maneb 7-10 days apartto clean up the plants. This will keep theepiphytic population from building up onthe plants by acting as a bacterial leaf spotsuppressant. Watch the weather andcontinue with a fixed copper Maneb sprayprogram on a 10-14 day interval if it is dry.If the weather is wet, use a 7 day sprayinterval. These sprays are to keep thebacterial leaf spot population down, as wellas to control other diseases. Do not waituntil you see bacterial leaf spot beforetrying to control it. This disease works toofast and once it becomes well establishedunder favorable weather conditions thesespray materials will not be able to controlit.

To manage insect pests, walk the fieldsregularly to monitor for beet armyworm,yellowstriped armyworm, hornworms, andcorn earworm. Use pheromone trap catchesto begin sprays for second generation cornborer or alerts from your countyCooperative Extension Service based on thecomputer model. Most sprays should targetEuropean corn borer unless beetarmyworm is present, but that isuncommon.

28

PEPPER HARVEST

FRESH MARKET PEPPERSFresh market peppers require 70-80

days from transplanting to the first harvest.First harvest usually occurs the last week ofJune in southern and western Kentucky,early July in central Kentucky and July 5-10in northern Kentucky. Begin harvesting inthe center of each 150 ft long row and pickdown the row to the roadways. Whenharvesting for fresh market, pick at themature green stage and handle carefully.Fresh market green peppers are normallyharvested when they attain full size butbefore they lose their dark green color.Mature green peppers ready for harvestwill be firm to the touch and stems andcalyxes should be fresh and green. Fruitwith soft, pliable thin walls and a palegreen color are too immature to harvest.Harvest before any visible chocolate or redcoloration or yellowing is apparent.Discard any peppers that are small,misshapen, diseased or damaged byinsects, hail, sunscald or other means toavoid handling these a second time duringgrading.

Do not pick into plastic bags, becausepeppers will heat up and quickly decay.Hard and rough picking containers maycause skin breakage or punctures andshould be avoided. Take care in dumpingoperations to avoid bruising and punctures.Pack only clean, undamaged, insect anddisease-free peppers.

Good harvest management is needed topack high quality peppers. Employeesmust be trained and supervised to avoidpepper damage. Pepper plants have brittlestems that break easily during harvest.Workers must use care during harvest toreduce plant damage. Good pickers snapthe fruit from the plant with a backward

twist. Some retailers prefer to havepeppers cut from the plant with a sharpknife or pair of shears, because the woundheals much faster and there is less loss todecay.

Picking buckets should be cleaned andsanitized before each day's harvest toprevent accumulated disease organismsfrom infecting sound peppers. Rinsebuckets with water to remove debris thenwash them in a sanitizing solutionconsisting of 3.5 ounces of 5.25 percentsodium hypochlorite (household bleach)mixed in 7.5 gallons of water.

Wet peppers should not be harvested,because surface moisture increases fieldheat accumulation in the load and increasesdisease development. Physical damageoccurs during bulk bin loading as peppersdrop onto hard wooden bottoms. Manysplit as they strike the surface, while othersare bruised. It has been demonstrated thatpepper loss during field loading cansignificantly be reduced by padding binbottoms. Placement of insulated carpetingin the bins reduced splitting and bruisingand resulted in a 40 percent decrease inloss. Used carpeting is available to mostgrowers, and its installation wouldimprove the quality and quantity of fieldharvested peppers.

Protect peppers from direct sunlightwhile holding them in the field. Sunscalddevelops quickly on exposed peppers inloaded bulk bins. Trucks loaded with thesebins should be parked under shade if thereis any delay (such as a noon meal break) inmoving them to the packing shed. Fieldpacked boxes of peppers should not beheld on flat bed trailers in the heat afterloading. It helps to cover the peppers toreduce heat buildup from sun exposure.

29

A study of the effect of delayed coolingon field packed peppers has shown thatshelf life can be reduced by one-half ifpeppers are allowed to set in full sunlightfor two hours after harvest.

Washing, grading & packingProper washing, grading, and packing

of fresh market bell peppers is critical tomarketing success. Roughly 2/3 of pepperproduction costs are involved inharvesting, cooling, packing and storage.For small operations a small grading linecan be used very successfully to wash andgrade the fruit. Fruit are gently rolled fromthe transporting containers and picked upby a conveyor belt. The peppers are thencarried beneath high pressure waternozzles, brushed and are often rolled oversponge donuts to dry them somewhat.

Fruit should never be washed bydunking them in water for a period of timeor left sitting in water, because the cut stemwill take up water leading to decay andreduced shelf life. See the Bacterial Soft Rotof Fruit section on the importance of watertemperature and the use of chlorine during thewashing operation. Fresh market peppersare generally not waxed or oiled. Next thepeppers are deposited on a rotatinggrading table. At this point the fruit arevisually sized, graded and any cull fruit areremoved.

Peppers are graded into "U.S. Fancy"(not less than 3 inches in diameter and notless than 3 1/2 inches long) and U.S. No. 1(not less than 2 1/2 inches in diameter orlength). All grades must have similarvarietal characteristics, be firm, fairly wellshaped, and free from damage caused byfreezing injury, hail, scars, sunburn,disease, insects, mechanical or other means.Free copies of USDA standards for gradesof peppers and other fruit and vegetables

are available on the internet at:http://www.ams.usda.gov/standards/vegfm.htm or can be obtained free of chargeby writing: USDA, Agricultural MarketingService, Fruit and Vegetable Division,Standardization Section, P.O. Box 96456,Room 2049-S, Washington, D.C.20090-6456. Peppers are usually packed in30 lb 1 1/9 bushel waxed corrugated boxes.Fruit size is designated as extra large, large,medium or small. Most buyers prefer theextra large or 55-60 count pepper size(Table 10). Medium sized fruit are usuallymoved through local markets and it isdifficult to move small peppers.

Table 10. Pepper Box Counts

Size Count/box

Extra large 55-65

Large 65-75

Medium 75-90

Small 90-100

PROCESSING MARKET PEPPERS Processing bell pepper harvest usually

begins in early to mid-August. They arepicked when red ripe. A sound ripepepper will remain in good condition for 7to 10 days after becoming fully ripe.Processing companies want only fully redripe peppers and do not want green orchocolate colored fruit. Green peppers cannot be ripened to a satisfactory red colorafter they are removed from the plant.Before harvesting for the first time,measure off 50 feet of row. If you can pickone half bushel or more of red ripe peppersfrom this 50 feet of row the field is ready toharvest.

Red processing bell peppers must besound, fully ripe and at least 2 1/2 inches

30

in diameter. An average acre of processingpeppers will need to be harvested 3-5 timesbetween mid-August and station closing(usually early October). Each harvest willrequire 12-18 hours of labor/acredepending on field size, layout, yield, labormanagement, amount of weeds, andmethod and frequency of harvest. Withoutaccess roads considerable time is spent orwasted carrying peppers out of the field.

STORAGECool peppers to 45-50°F by putting

them in the cooler as soon as possible afterharvest; cool rooms with forced airequipment will greatly speed the processand extend shelf life. Once fruit areprecooled, hold them at 45-50°F with arelative humidity of 90-95%. Pepperssuffer chilling injury when stored attemperatures below 40°F. Symptoms ofchilling injury are browning at the calyxend and surface pitting. At 35°F fruit willdevelop surface pitting after several days.Chilling injury usually does not show upuntil the pepper temperature is increased,usually at the market.

Do not store peppers with tomatoes,cantaloupes, apples or other produce thatgives off ethylene gas. Ethylene will causethe loss of the green chlorophyll pigment.

BELL PEPPER PRODUCTIONSUMMARY

To be successful perform all of these stepsin a timely manner.

U Determine your market. (See ID-134Marketing Options for Commercial VegetableGrowers). This is the first priority. Keep thebuyers informed of delivery times and amounts.Use packages suitable to the buyers needs.

U Select a variety that meets the demands ofyour particular market and growing conditions.

U Topped transplants from the south are adisease risk for both fresh and processingmarkets and should be avoided if at all possible.

U Take necessary steps to assure that disease-free plants are grown and planted.

U Select a site with medium-textured soilswhich provides good root penetration andmoisture holding capacity and has good airdrainage.

U Apply lime, phosphorus, potassium andminor elements according to soil testrecommendations. Avoid excessive nitrogenapplications which result in increasedproduction costs and delayed fruiting.

U Apply nitrogen according to therecommended fertigation schedule.

U Take necessary precautions to avoid frostinjury to early plantings.

U Space plants according to the variety andmarket. Good weed control is critical toestablishment of a good crown set of largepeppers. Fruit size tends to be slightly smalleron fruit set on the branch tips.

U Irrigate if soil moisture levels are low basedon soil tensiometer readings.

U Monitor pests and control them using provenmethods, equipment and timely applications.

U Harvest at the stage of maturity and sizethat your market requires. Handle pepperscarefully and move them promptly to coolingfacilities at their intended destination. No onewants small, immature, or damaged peppers.

U Take necessary steps to improve productionefficiency and reduce expenses. Records on costs

31

and returns are critical for improvement of youroperation. See ID 99 Horticulture CropEnterprise Cost and Return Estimates for asample budget.

36

Appendix 1

PEPPER INTEGRATED PEST MANAGEMENT FORM

COOPERATOR: SCOUT: FIELD #:

ADDRESS:

CITY: ZIP: VARIETY: ACRES:

COUNTY: PHONE: DATE PLANTED:

SOIL CONDITIONS WEATHER TIME/DATE:

WET MOIST DRY

LOOSE HARD LIGHT CRUST

COOL WARM HOTSUNNY CLOUDY RAINYCALM LIGHT STRONG WIND GROWTH STAGE:

INSECTS/DISEASES: 1 2 3 4 5 6 7 8 TOTAL AVG % INFESTATION

PHEROMONE TRAP INFORMATION

LURE TYPE# MOTHS

LAST VISIT# MOTHS

THIS VISITTOTAL FOR 2 WEEKS

(LAST + THIS VISIT) DATE LURES CHANGED

EUROPEAN CORN BORER

BEET ARMYWORM

PESTICIDES APPLIED RATE/ACRE DATE APPLIED

FERTILIZER APPLIED RATE/ACRE DATE/APPLIED

COMMENTS:

WEEDS:PREDOMINANT SPECIES

37

Appendix 2

ACTIVITIES BY MONTH FOR PRODUCTION OF RED BELL PEPPERS FOR PROCESSING

Apr. May Jun. Jul. Aug. Sept. Oct.

Land prep-plow X

Spread fertilizer X

Land prep-disc X

Disc herbicides X

Transplant with starter solution X

Cultivate/weed control X X

Irrigation/fertigation X X X X

Spray insecticide as needed using IPM X X X X

Spray fungicide X X X

Harvesting and hauling X X X

Labor hours per acre 2.0 10.5 8.5 9.0 37.0 53 20

38

Appendix 3

PREDICTING EUROPEAN CORN BORER DEVELOPMENT

The European corn borer is a seriouspest of corn and peppers in Kentucky. Cornborers overwinter as full-grown larvae incorn stubble. With the return of warmweather in the spring, development isresumed and the larvae pupate.Temperature plays a major role indetermining the rate of corn borerdevelopment. The European corn borer hasa 50" to 85"F temperature range at which itis most comfortable. Below 50"it will nowdevelop, and above 85"F development willslow dramatically. The rate of developmentof European corn borer can be predictedusing this relationship. Dr. Grayson Brownat the University of Kentucky developed adegree day model which accuratelypredicts the occurrence of the different cornborer life stages. It is recommended thatthese predictions be used in combinationwith field scouting or pheromone trappingin order to make management decisions.These predictions will alert you to when itis necessary to monitor pheromone trapsclosely and scout fields for corn borers.

A degree day for European corn borer isone of degree above 50"F over a 24-hourperiod. For example, if the averagetemperature for a 24-hour period was 70"F,then 20 degree days would haveaccumulated (70 - 50 = 20) on that day.These accumulations can be used to predictwhen corn borers will pupate, emerge asadults, lay eggs, and hatch as larvae. WithEuropean corn borer, begin accumulatingdegree days January 1 of each year.Accumulated degree day totals can becompared with the values in the tablesbelow that correspond to various cornborer life history stages. Tables areavailable for the first and second

generation, in some years a thirdgeneration may also occur. Values for thethird generation are not available. Valuescorresponding to initiation indicate whenthe earliest individuals of that stage mayappear. For example, a degree day value of750 would indicate that nearly 100% ofadults have emerged from pupae, of whichslightly more than 50% have flown, egglaying has begun, but is less than 25%complete, and that the earliest first instarlarvae may be present. This exampleillustrates the need to compare theaccumulated degree day total with valuesin several columns of the table. During thegrowing season there is usually a mixtureof different stages in a field. Because cornborers emerge at different times, not allcorn borers will be in the same stage at anyparticular time.

Current degree day accumulations areavailable for European corn borer as wellas other insects for many locations in thestate through the Agricultural WeatherCenter maintained by the UK Departmentof Agricultural Engineering. Up-to-dateEuropean corn borer estimates are availablethrough the World Wide Web using thef o l l o w i n g a d d r e s s"http://wwwagwx.ca.uky.edu/.”

39

European Corn Borer Life History StagesFirst Generation

Percentage Adult Flight Egg 1st Instar 3rd Instar 5th Instar

Initiation 550 610 750 1140 1420

25% 690 790 920 1220 1490

50% 740 850 960 1250 1520

75% 790 900 1000 1280 1550

Peak 900 990 1090 1350 1620

Second Generation

Percentage Adult Flight Egg 1st Instar 3rd Instar 5th Instar

Initiation 1660 1740 1860 2140 2370

25% 1880 2020 2160 2420 2800

50% 1950 2110 2250 2500 2930

75% 2030 2190 2330 2580 3060

Peak 2190 2360 2490 2720 3500