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Normalized difference vegetation index (NDVI), which is a measure of leaf greenness (chlorophyll content), is considered to be correlated with crop productivity. This study was conducted to examine genotypic variations for NDVI at different growth stages and its relationship to yield in winter wheat under terminal heat stress. Thirty winter wheat genotypes were evaluated at two locations in 2009–2010 and 2010–2011 in Uzbekistan. The NDVI was recorded at booting, heading, milk and dough stages. The wheat genotypes differed significantly for NDVI at each stage. Grain yield ranged from 3.9 to 6.1 t/ha. Wheat genotypes differed in per cent decline in NDVI from booting to dough stage. However, several high‐yielding genotypes maintained higher NDVI than low‐yielding genotypes when heat stress was evident. The findings suggest change in NDVI during heat stress could be a measure of tolerance. The positive correlation of NDVI with grain yield suggests that it could be used as an indirect selection criterion for identifying physiologically superior, high‐yielding wheat lines under terminal heat stress.

High grain yield and improved quality determine the commercial success of winter wheat (Triticum aestivum L.) varieties in Central Asia. This study was conducted to determine the effect of environment on grain yield, 1000-kernel weight (TKW), test weight (TWT), protein, and gluten content, and to identify superior wheat genotypes for yield and quality. Thirty winter wheat genotypes were evaluated in 3 years (2010-2012) over multiple locations. A genotype and genotype × environment interaction biplot analysis was used to determine the superior genotypes. There were significant effects of environment and genotype × environment interaction on yield and quality traits. The 30 wheat genotypes showed variations for grain yield (3.7-5.6 t ha-1), TKW (33.6-42.4 g), TWT (753-797 g/L), protein (13.3%-14.8%), and gluten (27.2%-29.5%) content. There was a significant positive correlation between grain yield and TKW in three out of seven environments. There was no correlation of grain yield with TWT, protein, and gluten content with one exception. There were different sets of five most superior genotypes for individual traits. However, certain genotypes were superior based on grain yield and quality traits. Gozgon, Elomon, ID800994.W/Vee//Lagos-12, Jaikhun, and Kroshka were the five most superior genotypes for four quality traits. Elomon, Gozgon, Jaikhun, ID800994.W/Vee//Lagos-12, and Kiriya were the five most superior genotypes based on grain yield, TKW, TWT, protein, and gluten content. This study demonstrates success in wheat breeding for combined high yield and improved quality in winter wheat. This study provides information on the combined stability of high yield and improved quality of the internationally important winter wheat genotypes. Therefore, the results of this study could be valuable for national and international winter wheat breeding programs to develop new varieties with high stable grain yield and quality.