HETEROGENEITY OF THE WICHITA WHEAT MONOSOMIC SET FOR GRAIN QUALITY AND AGRONOMIC TRAITS

Homogeneity between the chromosome lines of an aneuploid set is necessary to avoid supplemental effects of the genetic background. The objective of this study was to determine the homogeneity of the 'Witchita' (WI) winter wheat (Triticum aestivum L.) monosomic set for grain quality and agronomic traits. Disomics were produced from 20 chromosome lines of the WI monosomic set and 2B disomics from 'Cheyenne' monosomic 2B. Three replications were planted in a field study. Disomics of 5B lines were later heading, shorter, and 2.25% higher in grain protein concentration (GPC) than the WI check. Disomics of 7B lines were shorter and had a lower 100 kernel weight. Disomics of 2B lines were similar to the WI check for GPC, height, and mixogram peak; however, they were later heading and had lower 100 kernel weight. The average GPC of disomic lines from 4B, 6D, and 7B were about 1.5 to 3.0% lower than those of 1A, 5A, 5B, and 6B, while 7A dosmics were 1.5% and 2.25% lower than 5A and 5B, respectively. Mixogram peak and tolerance of the disomics were similar to the WI check; however, lines from 1A, 3B, 5B, 6A, and 6B had shorter mixing times than lines from 4D, 6D, and 7B. Significant variation for several traits measured, specifically GPC, plant height and heading date, supports the contention that homogeneity studies should accompany aneuploid studies, especially when quantitative traits are measured.