Evaluation of TC Blends (R) used in high oil maize production

The Top Cross(R) grain production system is rapidly gaining popularity in t he U.S.A. as the preferred method of producing high oil maize. A blend (TC Blend(R) seed maize) of two types of maize is planted to produce TopCross(R ) high oil grain. The TopCross(R) system may minimize the yield disadvantag e associated with conventional high oil maize hybrids and enhance grain nut rient composition. Evaluations of TC-Blends(R) were preformed in 1997 and 1 998 at two Ohio locations to determine the agronomic performance and grain quality characteristics of TC Blends(R) adapted to eastern U.S. Corn Belt g rowing conditions. Single cross normal and high oil hybrids were also inclu ded in the evaluation. There were significant differences in grain yield am ong the TC Blends(R) evaluated-up to a 2.4 t/ha and 1.5 t/ha difference bet ween the highest and lowest yielding TC Blends(R) in 1997 and 1998, respect ively. Although yields of most TC Blends(R) were less than the check hybrid s, several TC Blends(R) produced grain yields that were similar to checks. TC Blend(R) yields were greater than or equal to the single cross high oil hybrids. TopCross(R) grain oil content differed significantly among TC Blen ds(R) by as much as 1.7 and 2.9 percentage points in 1997 and 1998, respect ively. The oil content of TopCross(R) grain, averaged across entries, locat ions, and years, was 2.9 percentage points higher than normal maize hybrids and 1.3 percentage points greater than the single cross high oil maize hyb rids.