An Experimental Approach to Determine the Economic Incentive for Breeding Corn, Cotton, and Soybean Cultivars Adapted to Reduced-tillage Systems

Crop cultivars now being grown in no-till production systems were developed by selecting for performance in conventionally tilled environments. In order to maximize production of corn (Zea mays L.), cotton (Gossypium barbadense L.), and soybean [Glycine max (L.) Merr.] in a no-till environment, it may be necessary to select for performance under the same conditions. The economic incentive for developing cultivars to produce in no-till environments cannot be determined without measuring the genotype times tillage interaction using genotypes that have not been selected for previous performance in a specific tillage regime. The experimental approach outlined here for determining the potential for improving performance in no-till systems is two-fold. The first experiment entails measuring crop and root growth rates, agronomic characteristics, and yield of commercial cultivars in conventional and no-till environments. Results from the first study should help identify cultivars with superior performance in no-till regimes and perhaps assist in establishing selection criteria for cultivar development programs. The second experiment measures the same performance parameters using randomly selected experimental strains that have not undergone selection in a specific tillage system. The second experiment should provide a reasonable measure of the genotype times tillage interaction for cultivars developed from crosses between elite parents, the source of most new commercial cultivars.