Download - North Carolina Corn Insect Pest 2014 Update
North Carolina Corn Insect Pest 2014 Update
Dominic Reisig NCSU Entomology
Contents of This Presentation• Refuge compliance• Does corn earworm impact corn yield?• Cry1F-resistant fall armyworm
• Seed treatment value for NC corn• Resistance development of corn earworm to Bt• Stink bug management in corn
Research Issues Not in This Presentation
Description Caterpillar Traits Rootworm Traits
Agrisure CB/LL Cry 1AB (Bt11) None
Agrisure 3000GT Cry 1AB (Bt11) Cry 3A (modified)
Herculex I (HX1) Cry 1F (HX1) None
Herculex XTRA (HXX) Cry 1F (HX1) Cry 34/35Ab1
YieldGard VT Triple (VT3) Cry 1AB (YGCB) Cry 3Bb1
Genuity VT Triple Pro (GENVT3P) Cry 1A.105 + Cry2Ab2 Cry 3Bb1
Genuity VT Double Pro (GENVT2P) Cry 1A.105 + Cry2Ab2 None
Genuity VT Double Pro RIB (GENVT2P RIB) Same as above + RIB * None
Genuity or Dow AgroSciences SmartStax (GENSS or SSX) Cry 1A.105 + Cry2Ab2 + Cry 1F (HX1) Cry 3Bb1 + Cry 34/35Ab1
Genuity or Dow AgroSciences SmartStax RIB (GENSS or SSX) Same as above + RIB * Same as above + RIB *
Agrisure Viptera 3110 Cry 1Ab (Bt11) + VIP3A (MIR162) None
Agrisure Viptera 3111 Cry 1Ab (Bt11) + VIP3A (MIR162) Cry 3A (modified)
Agrisure Viptera 3220 Cry 1Ab (Bt11) + VIP3A (MIR162) + Cry1F (HX1) None
Optimum Intrasect Cry1Ab (YGCB) + Cry 1F (HX1) None
Optimum AcreMax Cry1Ab (YGCB) + Cry 1F (HX1) None
Optimum AcreMax Xtra Cry1Ab (YGCB) + Cry 1F (HX1) Cry 34/35Ab1
Traits of Selected, Commercially Available Bt Corn Products
* Non-Bt Refuge in Bag Slide adapted from Scott Stewart, U. Tennessee
* Unless Cry1F-resistant fall armyworm is present Slide adapted from Scott Stewart, U. Tennessee
Traits / Brands Corn borers Cutworm Corn earworm Fall armyworm
Western corn
rootwormAgrisure CB/LL Excellent Poor Fair Good None
Agrisure 3000GT Excellent Poor Fair Good GoodHerculex I (HX1) Excellent Good Poor Very Good * None
Herculex XTRA (HXX) Excellent Good Poor Very Good * ExcellentYieldGard VT Triple (VT3) Excellent Poor Fair Fair Excellent
Genuity VT Triple Pro (GENVT3P) Excellent Poor Good Very Good Excellent
Genuity VT Double Pro (GENVT2P) Excellent Poor Good Very Good None
Genuity VT Double Pro RIB (GENVT2P RIB) Excellent Poor Good Very Good None
Genuity or Dow AgroSciences SmartStax (GENSS or SSX) Excellent Good Very Good Very Good * Excellent
Genuity or Dow AgroSciences SmartStax RIB (GENSS or SSX) Excellent Good Very Good Very Good * Excellent
Agrisure Viptera 3110 Excellent Good Excellent Excellent NoneAgrisure Viptera 3111 Excellent Good Excellent Excellent Good
Agrisure Viptera 3220 Excellent Very Good Excellent Excellent None
Optimum Intrasect Excellent Very Good Fair Very Good * None
Optimum AcreMax Excellent Very Good Fair Very Good * None
Optimum AcreMax Xtra Excellent Very Good Fair Very Good * Excellent
Relative Efficacy of Selected, Commercially Available Bt Corn Products
Traits / Brands Refuge Requirement
Agrisure CB/LL 50% In-field, adjacent, block ½ mileAgrisure 3000GT 50% In-field, adjacent, block ½ mileHerculex I (HX1) 50% In-field, adjacent, block ½ mile
Herculex XTRA (HXX) 50% In-field, adjacentYieldGard VT Triple (VT3) 50% In-field, adjacent
Genuity VT Triple Pro (GENVT3P) 20% In-field, adjacent
Genuity VT Triple Pro RIB (GENVT3P RIB) 20% + RIB * In-field, adjacent
Genuity VT Double Pro (GENVT2P) 20% In-field, adjacent, block ½ mile
Genuity VT Double Pro RIB (GENVT2P RIB) 20% + RIB * In-field, adjacent
Genuity or Dow AgroSciences SmartStax (GENSS or SSX) 20% In-field, adjacent, block ½ mile
Genuity or Dow AgroSciences SmartStax RIB (GENSS or SSX) 20% + RIB * In-field, adjacent, block ½ mile
Agrisure Viptera 3110 20% In-field, adjacent, block ½ mileAgrisure Viptera 3111 20% In-field, adjacentAgrisure Viptera 3220 20% In-field, adjacent, block ½ mile
Optimum Intrasect 20% In-field, adjacent, block ½ mileOptimum AcreMax 20% + RIB * In-field, adjacent, block ½ mile
Optimum AcreMax Xtra 20% + RIB * In-field, adjacent, block ½ mile
Refuge Requirements (Southern US) of Selected, Commercially Available Bt Corn Products
* Non-Bt Refuge in Bag Slide adapted from Scott Stewart, U. Tennessee
Why refuge?
Slide adapted from Department of Soil and Crop Sciences at Colorado State University
Example Refuge Configurations
Image adapted from Canadian Corn Pest Coalition
Common Refuge Questions• Can the refuge be protected from lep. pests?
– Yes, using non-Bt insecticides• How should the refuge hybrid be selected?
– Chose a hybrid with a similar maturity and plant it as close in time as possible to the Bt hybrid
• What happens to those who don’t plant refuge?– Required by law through EPA– Contract occurs at time of purchase of Bt hybrid– Warning letter on first offense, with compliance
assessment the following year– No Bt corn after second offense (in consecutive year)
Common Refuge Questions• Who checks for compliance
– Independent third parties• Telephone survey, on-farm visits
• Are seed purchases tracked?– Of course, but companies don’t share information
• How can I know the refuge requirement?– Check the bag tag– Online search “refuge calculator”
• Yes, there is an app for that- iPhone and Android…
Common mid- to late-season lep. pest
Occasional mid- to late-season lep. pests
Cutworm
Armyworms
Southern cornstalk borer
European corn borer
Corn earworm
No control• Agrisure RW• Herculex RW• YieldGard Rootworm• YieldGard VT
Rootworm/RR2
Poor-fair control• Herculex I• Herculex XTRA
Fair-good
Very good• YieldGard VT2 Pro• YieldGard VT Triple Pro • SmartStax
• Agrisure CB/LL• YieldGard Corn Borer• Agrisure CB/LL/RW• Agrisure GT3000• YieldGard Plus• YieldGard VT Triple
Corn earworm control with Bt hybrids
Excellent• Agrisure Viptera
Slide from F.P.F. Reay-Jones, Clemson U.
To date, I have not documented a single yield loss due to corn earworm feeding in the ear in
North Carolina
Does corn earworm impact yield?
Example of past experiment- 2011
Does Corn Earworm Affect Yield?• Plots of 14 rows x 50 ft planted in Florence, SC, and in Plymouth, NC
(n = 4 replications).• Near-isolines for Bt and non-Bt hybrids (HX1; HX1 + YGCB; VT3;
VT2Pro).• Applications of Prevathon (20 oz/ac) twice a week (15 applications in
Florence, 18 applications in Plymouth) using a backpack sprayer.• Created treated and untreated subplots
• Sampled 20 ears per plot for corn earworm injury and yield
Florence, SC Plymouth, NC
Area of Kernels Injured by Earworm in 2012
= hybrids shared same genetic background
Florence, SC Plymouth, NC
Area of Kernels Injured by Earworm in 2013
= hybrids shared same genetic background
Relationship between feeding and yield
Conclusions• Corn earworm did not affect yield (NC or SC)• Hybrids should be chosen based on other agronomic
considerations than earworm• Bt is probably still necessary for stalk pests (southern
cornstalk borer & European corn borer)• Some of these genes active against corn earworm
also have activity on other pests– May have fit for late-planted corn
– Aflatoxin level may be reduced by eliminating earworm, but effect is highly dependent on hybrid genetics and environment
armyworm
Safe for any use
Fit only for cattle, will not accept above this level
Non-Bt
Cry1F-resistant fall armyworm found in Hyde County, 2013
What adjustments should we make in 2014?
• Hybrids with Genuity SmartStax, Herculex and Optimum Intrasect contain Cry1F– Widestrike countains Cry1F + Cry1Ac
• Closely monitor corn and cotton for resistance– August
• Plant refuge• Plant refuge• Plant refuge