Analysis of Genotype-by-Environment Interaction in Winter Wheat Growth in Organic Production System

Abstract

The goal of this study was to evaluate the performance of 36 wheat winter (Triticum aestivum L.) lines in organic systems in three locations in Nebraska, to compare the performance of the released cultivars with experimental lines to help in the process of selection, to study the magnitude and behavior of genotype-by-environment interaction for grain yield, anthesis date, plant height, protein content, grain volume weight and vegetation index, and to identify the more stable genotypes. Linear mixed models and site regression model was implemented for reaching the objectives of the present research. Genotypic and GE interaction are significant across the three locations for all traits except for anthesis date. Environment were significant for the six traits. Yield is negative correlated with protein content and plant height. In general the genetic correlation explained more of the genotype performance, although the GE interaction was significant. The best genotypes for grain yield across the three environments were genotypes NW03666, SD07165, NE07444 and Overland. For vegetation index the best lines were: Lyman and Buckskin. For grain volume weight the best lines were: Lyman, NW03681, Danby and Goodstreak. For anthesis date all genotypes were similar. For plant height, the best lines were Goodstreak, Buckskin and Clarkscream. For protein content, the best lines were Goodstreak, Karl92, Lyman, and Clarkscream. In general the average grain yield of the experimental lines was better than the released lines. For anthesis date, the performance was similar between experimental and released lines. However, for vegetation index, plant height, grain volume weight and protein content, the average performance of the experimental lines was lower than the released lines.