Western corn rootworm resistance in New York

decrease font size  Resize text   increase font size       Printer-friendly version of this article Printer-friendly version of this article


Elson Shields reported a corn field in Cayuga County showing symptoms of a failed corn rootworm (Cry3Bb1) Bt hybrid. The field planted to a Monsanto VT3 single event Bt hybrid has extensive goose necking, lodging and severely pruned roots characteristic of corn rootworm (CRW) injury.

Aerial view of CRW resistant Bt corn hybrid field damaged by corn rootworm, Cayuga County, NY. Photos by Elson Shields, Cornell Entomology.

Performance problems with Cry3Bb1 were first reported in the Minnesota and Iowa in 2009 (and Nebraska since 2007). Since then similar reports have emerged from locations in Colorado, Illinois, Kansas, Missouri, Nebraska, South Dakota, and Wisconsin. This recent sighting in New York is among our first in the northeast. The following information is drawn from the Cornell and Penn State articles cited below.

Problem fields share the following characteristics:

  • Planting corn continuously for multiple years (typically more than four years)
  • Using the same (Cry3Bb1) Bt trait year after year as a single event.
  • Refuge compliance was (often) problematic (no/not enough refuge, or refuge too far from the Bt field) on farms with unexpected damage.

Warning signs of potential corn rootworm resistance:

  • Large number of CRW beetles in the field, possibly leaf feeding, clipped silks resulting in poor pollination.(this is a very weak indicator since the beetles are strong fliers)
  • Unexpected lodging and root damage that cannot be explained by an agronomic or environmental problem, or presence of another root-feeding pest.

Recommendations to reduce the selection pressure on corn rootworm to develop resistance to CRW-BT corn:

  • ROTATE-ROTATE–ROTATE corn with non-host crops such as alfalfa, soybeans, small grains.
  • Fields with low levels of CRW pressure should be planted to a non-CRW-BT variety. These fields are typically first or second year fields. First year fields do not need any rootworm insecticide, but second year fields may need a high rate of seed treatment or a reduced rate of soil insecticide.
  • Only plant CRW-BT corn varieties in fields with high rootworm pressure. These fields are typically continuous corn fields in 3 or longer years of continuous corn.

For more information see:

Corn Rootworm Resistance to BT-Corn Reported

 Managing Western Corn Rootworm Resistance to Bt on the Fringe


Buyers Guide

Doyle Equipment Manufacturing Co.
Doyle Equipment Manufacturing prides themselves as being “The King of the Rotary’s” with their Direct Drive Rotary Blend Systems. With numerous setup possibilities and sizes, ranging from a  more...
A.J. Sackett Sons & Company
Sackett Blend Towers feature the H.I.M, High Intensity Mixer, the next generation of blending and coating technology which supports Precision Fertilizer Blending®. Its unique design allows  more...
R&R Manufacturing Inc.
The R&R Minuteman Blend System is the original proven performer. Fast, precise blending with a compact foot print. Significantly lower horsepower requirement. Low inload height with large  more...
Junge Control Inc.
Junge Control Inc. creates state-of-the-art product blending and measuring solutions that allow you to totally maximize operating efficiency with amazing accuracy and repeatability, superior  more...
Yargus Manufacturing
The flagship blending system for the Layco product line is the fully automated Layco DW System™. The advanced technology of the Layco DW (Declining Weight) system results in a blending  more...
Yargus Manufacturing
The LAYCOTE™ Automated Coating System provides a new level of coating accuracy for a stand-alone coating system or for coating (impregnating) in an automated blending system. The unique  more...
John Deere
The DN345 Drawn Dry Spreader can carry more than 12 tons of fertilizer and 17.5 tons of lime. Designed to operate at field speeds up to 20 MPH with full loads and the G4 spreader uniformly  more...
Force Unlimited
The Pro-Force is a multi-purpose spreader with a wider apron and steeper sides. Our Pro-Force has the most aggressive 30” spinner on the market, and is capable of spreading higher rates of  more...
BBI Spreaders
MagnaSpread 2 & MagnaSpread 3 — With BBI’s patented multi-bin technology, these spreaders operate multiple hoppers guided by independent, variable-rate technology. These models are built on  more...


Comments (0) Leave a comment 

Name
e-Mail (required)
Location

Comment:

characters left


Field Profit Planner Dashboard

With GEOSYS Field Profit Planner, you can plan for the future using information from previous years. Agronomic decisions made during ... Read More

View all Products in this segment

View All Buyers Guides

Feedback Form
Feedback Form