INTRODUCTION

This assignment explains the growing of vegetable onion crop which was undertaken during the

period of January to April. It also discusses how onion was prepared from nursery bed

transplant and states the botanic name of it as well as explaining the time the seeding was

transplanted. It further state two soil and climate requirement, give reason why water is

required, crop weeding management, application of chemicals for vegetable onion crop and

calculation of plant population.

Like any other crop, onion is a leafy green biennial plant grown as annual vegetable crop and it

has long green and shallow leaves and flattened stem. The lower part of the hallow leaves

become swollen to form a distinct bulb which varies in size (small, medium, large) shape

(flatted, round, globular) color (white, yellow, red) and pungency (state to variety). Onion

vegetable crops are best suitable for growing in the open ground contains silt and loam soil

Bruchac (1994) say that "onion primarily originated from Asia and Iraq (generally the middle

east)and it has a botanic name called Allium cepa." Onion is in the family of Amyryllidaceae

and is monocotyledons and normally has some of the characteristic such as: store carbohydrate

in a usually swollen basal portion, posses a characteristic odors and flavor, develop a non

extensive root system, and produce perfect insect pollination flowers.

Onion is propagated by seed and by onion sets i.e. using bulb. Kalley (2012) postulated that

there can be considered overlap in these categories and not all varieties will perform the same as

to their maturity one year to the next.

The best way or time for onion planting is January to April and august to December. Early

planting promote high yield but the percentage of plants that bolt is high. Late planting leads to

small bulbs and low yield. To count for climatically, allium cepa grows wells in semi-arid

conditions with less or no front and needs cool temperature range during the seeding stage and

moderately high temperature range during building stage (Amiran:2006). At below 10-15 only

leafage occurs, between 15-21C bulbs begin to form and between 21-26*C good bulb

formation and matures properly with reference to ADEO (2013). Only short day or day neutral

bulb onion cultivars can be grown in Zambia. Long day cultivars from the northern hemisphere

will not produce bulbs in the tropic including Zambia. The soil should be well drained and not

subject to water logging. The allium cepa grow optimally well on fertile. Friable soil such as

loam soil which are supplied with humus and PH of between 6.0 and 6.5. heavy soil which bake

after rains or irrigation are not desired.

Furthermore it uses as a flavor in relish and soup, Alliuir, cepa serves to enhance human

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memory and to fight certain health relate problems like some forms of rash.

EQUIPMENT OR TOOLS

Tools that were used in this vegetable Allium cepa crop production include: hoc, sprayer

garden fork, sprinkler for water and portable

PLANT BEDS PREPARATION AND NURSERY

Having find the required land for the vegetable onion crop, 1000m nursery in enough for

planting a hectare or 2500m of plant bed, it will be 400cm squire (20cm x 20cm) seedbed

(also called nursery bed) was prepared by using a hoe to the depth of 25cm and the basal

fertilizer (compound D) was spread, the soil was leveled at selected site at home in the

garden (by direct proportion or scaling down) and raised to about 15 cm in the rain season

and spacing between the 2 row of sown onion seeds on the nursery bed was 10cm as per

recommendation.

25cm by 25cm of (1000cm) plant bed was similarly prepared using a hoe in the leveled.

Selection for the sites of both the nursery and plant beds was primarily based on the pre-

determined PH values arid less considerable previous record of attack from onion pests or

insects and diseases.

Following the recommended seed rate of 3kg of seeds for 1000m, 0.12 grams seeds were

sown (after calculation by direct proportion from the seed rate) on the nursery bed into 2

rows at a depth of 1.2 cm and covered with grass were germinated by both irrigation and

rains.

TRANSPLANTING

Before transplanting the seed bed that was planted in the bed, it was watered and waited for

a day to avoid having an over wetted seedbed and later then transplanted. Actual process

of transplanting was done when seedlings were 6 weeks old and 13 cm high in the evening,

the seedling was transplanted in the evening to promote the transplanted seedlings enough

chance to establish their roots in the new bed for water and nutrient absorption and for

upright support before sunrise after dawn which threatened death of seedlings due wilting

or drying up. Poorly developed seedlings were discarded. Immediately after, irrigation was

performed until 2 weeks before harvest twice per day (in the morning and evening) not

only to keep the plants alive, but also for upright hydro support since onions, like other

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vegetable arc herbaceous plant (i.e. non woody or monocotyledonous plants) which need

water for hydro skeletal upright growth. The vegetable onion plants need water for

biochemical process primarily photosynthesis in presence of carbon dioxide and sunlight to

make carbohydrate and other nutrients. It's combined with atmospheric carbon dioxide to

form plants foot such as carbohydrates which is needed for respiration in onion and as a

starting point for the manufacturing of other nutrients like protein and oil. Furthermore,

controlling the tales through hydrotropism. Water is used to dissolve plant nutrient for

absorption from the planted soil and translocation In addition water serves as a medium for

transportation (nutrient absorb salt so on even to remove other unwanted pathogens and waste

(carbon dioxide or metabolized chemicals). Watering by the plant bed was stopped 2 weeks

before harvesting in order to start the curing process.

Immediately after preparation (before onion seedlings transplantation) 240 mg (or 0.24g) pre

determined 75% soil pesticide was sprayed on the plant bed in much the same way the nursery

bed was sprayed with 96mg (or O.o96g) of decthal 75% soil pesticide before sowing following

the recommendation shown below.

Though the recommended inter (i.e. between rows) and intra (i.e. within rows) row spacing of

40-60 cm and 30-60 cm respectively, onion seedlings were transplanted from the nursery bed to

the plant bed with the inter and intra row spacing of 12cm and 10cm respectively following the

small size (i.e. 1000cm or 25 cm by 40 cm) of the onion plot, hence they were 2 rows, 4

columns and 8 transplanted seedlings in total in the plant bed.

The recommended onion plant population is 40000 plant/ hectare or 10000 plants/ lima. It is also

recommended in a flat area of 50m x 50m in between the plants, there must be 3 rows in a bed

and 45 cm between the plants in a row. Based on this recommendation, below shows the

calculation for the population of transplant onion plants on % lima plots.

ONION POPULATION % LIMA PLOT

The recommendation population on onion is 10000 Lima or 40000 hectare. This means that on 1

lima plot, the recommendation number of onion seedlings to be planted are 10000 such as 1 lima

= 10000 onion seedlings, then recommendation number of onion seedlings to be planted on a %

lima plots will be represented by x and calculated by direct proportion as follows:

1 Lima = 10000 onion seedlings 3/4 Lima= x X=3/4 x 10000=7500 onion seedlings

4 Lima= 1 hectare but 1 Lima = 50m x 50m = 2500m

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MANAGEMENT OF WEED

After seedlings transplanted, hand weeding was effectively used to remove most weed species.

In order to reduce crop damage by the use of mechanical tools such as a hoe, hand weeding was

conducted when both the onion plants and weeds were small. In addition plants weed management

includes the stale method which did not involve the use of habiholder cultivation of the desired

area several times as weeds emerge before planting shallow inter cultivation controlled weeds and

aerated the plant bed soil.

Like the nursery bed, the onion planted bed was surely made it was all time weed free in order

to reduce competition for light, nutrients, water, and space between the onion crops and weeds

especially also that onion grows more slowly and is less competitive with weeds. Otherwise

some weeds are better nutrients and water competitors than onion and hence may deprive onion

plants of these requirements. Onion vegetable was all time weed free not only to reduce harvest-

able bulbs through competition and interfering with harvesting process by disturbing hand

harvesting, but also weeds can also harbor destructive insects and diseases that can severely

damage the onion. The 1000cm onion plot was monitored periodically to identify the need for

post emergence weed control measure.

APPLICATION OF FERTILIZER

Considering the recommendation that is required, the total predetermined of 4g of ammonium

nitrate (A/N) per hectare was applied and incorporated well in the soil and to avoid excess

application nitrogen at once which may lead to thick neck effect, the application of this amount

of A/N was done in two phases. In second week after transplanting, 2g of A/N per hectare was

applied and fourth week after the first application in phase one while the other 2g of A/N was

applied four week after the first application in phase two. Considering the recommendation, the

pre determined 8g of compound D was applied and incorporated well in the soil at preparation

nursery and plant beds.

The regime for top dressing fertilizer (ammonium nitrate or A/N) per hectare

regime Amount of top dressing fertilizer (A/N) pre hectareWeek 1-3 50kg ammonium nitrate per week + 120kg poly feed

Week 4-7 50kg ammonium nitrate per week + 7.5 multi k

Week 8- 10 20g multi k per week

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FromADOE02013

The basal dressing fertilizer (compound D) requirements (kg/ha)

Management level Basal dressing (kg/ha)Small scale Compound D 200Medium scale Compound D 400

Also from ADOE02013

Upper fertilizer was applied after the weeds were controlled and removed. As per

recommended amounts of two different fertilizers shown in the table. The following

calculation show how the right amount of applied basal Dressing fertilizer (compound D) after

preparing the plant bed and top Dressing fertilizer (A/N) after onion seedlings transplantation to

plant bed were done.

Basal Dressing fertilizer (compound D)

Considering the reference above, onion requires 200kg of compound D fertilizer per hectare as

per recommendation i.e. the recommendation amount of D on 1 hectare plot is 200kg.

200kg of D= 1 hectare where 1 hectare =4 lima=2500m (=50m by 50m)

Onion plot was 1000cm or O.lm since 1m is equivalent to 10000cm. thus the total amount of

applied D. compound (D) fertilizer is represented by y and was calculated by direct proportion

as follows:

200kg= 2500m Y = 0.1m

Y=200 x 0.1/2500 = 2/2500= 0.008 kg of compound D= 8g of compound D

Hence on the 1000cm (or O.lm) onion plot or plant bed, 8 gram of compound D fertilizer was

applied and incorporated well in the soil preparation plant beds.

To Dressing fertilizer (Ammonium nitrate or A/N)

With reference above. Onion requires 100kg of ammonium nitrate (A/N) fertilizer per hectare as

per recommendation i.e. the recommendation amount of A/N on 1 hectare plots is 100kg:

100kg = 1 hectare where 1 hectare =41ima=2500m (=50m by 50m)

Onion plot was 1000m or O.lm since 1m is equivalent to 10000cm. thus the total applied A/N

fertilizer is represented by Z and was calculated by direct proportion as follows:

100kg =2500m Z =0.1m

Z=l 00 x 0.1/2500-1/2500=0.004 kg of A/N- 4g of A/N

Hence on the 1000cm or 0.1 m onion plot or plan! bed, 4 grains of ammonium nitrate (A/N)

fertilizer was applied and incorporated well in the soil: 2g of A/N was applied two weeks after

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transplanted and another 2g of A/N four weeks after the first application.

Commonly compound D was calculated for the 400cm (0.04m) nursery plot.

APPLICATION OF PESTICIDE

Both the onion seeds is the 400cm nursery bed and seedlings in the nursery and 1000 cm

planted were treated from pests that attacked the vegetable using the recommended chemical

pesticides (Dacthal 57% and malalhion 25% wp) as per rate of recommendation shown before.

Preventive measure and careful scouting were done to minimize or eliminate any potential

problem. Soil borne insects such as ( cutworms, onion maggots, wireworms etc.) were

controlled with pre-plant applications of an appropriate soil pesticide. Foliar pests (small leaf

eating caterpillars) were also controlled with foliar pesticide.

By direct proportion the amount of soil pesticide (Dacthal 75%) that were sprayed on the 400 cm

nursery bed before sowing and on the 1000cm before the transplantation of onion seedlings to

plant bed were 96 mg and 240 mg respectively following the recommendation giving in

information above.

Similarly by direct proportion the amount of foliar pesticide (Malathion 25% WP) that were

sprayed on the 400cm nursery bed 2 weeks after the emergence of seeds and the 1000 cm 4

week after the onion seedlings transplantation to planted were 56mg and 140 mg respectively as

per recommendation shown above.

Recommendation types and qualities of onion pesticide

Onion production stage Insecticide type Recommendation

amount

Actual sprayed amount

Before sowing in seed

bed

Dacthal 75% /

malathion 25% WP

6kg/ha 73.5 kg/ha 96mg(0.096g) /56mg

/(0.056g)Before transplantation

in plant bed

Dacthal 75%

/malathion 25% WP

6kg/ha/3.5kg/ha 240mg (0.24g)

140mg(0.14g)

1 ha=2500m, 1m-1000cm and 1 kg=1000g=1000000mg.

To avoid stand loss seed com maggots, the fields containing high levels of organic matter were

avoided.

Observations; The onion bed [nursery and plant beds] were regularly checked particularly

twice a day i.e. early in the morning and late in the afternoon and all the observations of onions

growth any other usual happening on the plots were recorded. The monitoring of the beds was

periodical and aimed at evaluating the success of the weed management program, application of

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pesticide and fertilizers, among other activities and to determine the need for further pesticides

and fertilizers application, addition weed control measures and so on.

Table 1,4; Various observations that were made alter several post-transplanting works

Activities Observation on Onion Plants bed

After 27 days of transplanting and weeding Good response; Faster rate of groeth

After 2 1 days of pesticides spraying Good response; health growth, greenAfter 15 days of fertilizer application Good response; faster rate of growthDiscussion; the project of onion production was embarked on 1 January, 2015 on a 1000cm

Plot and manual harvesting was done on 30 April, 2015 implying that the project took

particularly 16 weeks to complete. As maturity approached, the tops of onion plats began to bend

and fall over, Harvesting started when about one third of the tops have fallen over.

During this period of production, one challenges which was encountered was that effect weed

control was often more difficult to achieve because onion grows more slowly and is less

competitive with weeds. Another challenge that was faced was the small size of the onion plot

or plant bed. The 1000cm [25cm by 40cm] onion plot was too small to accommodate at least 8

onion plants hence resulted in reducing the recommended intra row spacing from

recommended 40-60 cm to 12 cm and from 30-60 cm 10 cm respectively. This resulted in the

subsequent reduced the numbers of number of rows [2], columns [4] and onion population [8

onion plants] in the plan-bed. Beside, mobilization of financial resources to provide other

materials like more pesticides and other requirements was a stressful setback.

Conclusion: in conclusion onion production was successful with excellent yield despite the

challenges and its tiresome and stressful nature

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REFERENCE

ADEO (2013) Agriculture diary for extension officer January to June. Version 10

ministry of agriculture and livestock.

KALLEY, W. (2012) Georgia onion research extension report. University of

Georgia, georgia

AMIRAN, K.(2006) Guidelines for onion growing. Lusaka Zambia: star

technology amiran limited Zambia.

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Botanic name called allium cepa

Onion is in the family of amyryillidacea

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