Wednesday, November 15, 2006

Evaluating the Agronomic Performance of Short Season Bt Hybrids in Late Planting Environments in Ohio.

Peter Thomison, The Ohio State University, Hort.& Crop Sci. Dept, 2021 Coffey Rd., Columbus, OH 43210-4068, Allen Geyer, The Ohio State University, 2021 Coffey Rd, Columbus, OH 43210, Brad Miller, Monsanto Company, 91 E Street, Ashville, OH 43103, and Jeffrey Taylor, Monsanto, 8516 Graw Road, Arcanum, OH 45304-9421.

In one out of five years, a significant number of corn acres are planted late in Ohio, usually as the result of excessive rainfall. The use of short season Bt hybrids to minimize the impact of harvest delays on the agronomic performance of late planted corn has received little attention. A study was established at six Ohio sites in 2004 and 2005 to develop a better understanding of short season Bt hybrid response to late planting conditions, with regard to yield potential, stalk and grain quality. Ten Bt corn hybrids and their conventional isolines (conventional hybrid counterparts) representing a range of maturities from 96 to 108 days relative mature were planted after June 1. Plots were harvested on two dates (mid/late Oct. and late Nov./early Dec.). Although European corn borer injury was generally either moderate or low, the Bt hybrids consistently out yielded the non-Bt isolines across locations. Grain moisture averaged higher in the Bt hybrids. Although stalk lodging varied considerably across locations, lodging was generally comparable for the Bt hybrids and isolines. With harvest delays, the Bt hybrids continued to exhibit significant yield advantages over the non Bt isolines. However at several locations the differences in yield between the Bt and non Bt hybrids decreased with later harvest. Grain moisture remained consistently higher for the Bt hybrids with harvest delays. Stalk lodging increased sharply on the second harvest date and at some sites lodging was higher in the Bt than non-Bt corn. The increase in lodging may explain in part the reduced yield differential between the Bt and non-Bt isolines on the second harvest date.

Handout (.pdf format, 879.0 kb)