Evaluation of normalized difference vegetation index (NDVI), yield-related traits, and stripe rust in a winter wheat population, and selected checks in Ontario, Canada

Doubled haploid (DH) winter wheat population ‘25R56’/’E1007R’ was evaluated for yield-related traits across four environments in Ontario, Canada. The objectives were: (1) to evaluate agronomic traits (plant height, heading date, yield and test weight) and normalized difference vegetation index (NDVI); (2) to calculate the correlations among evaluated traits, and (3) to compare population performance with selected check varieties. Experiments were conducted at Ridgetown and Elora in 2015 and 2016. Widespread stripe rust occurred across Ontario in 2016. Yield showed a positive correlation with sum-NDVI (r = 0.87, p < 0.01) and test weight (r = 0.65, p < 0.01), while heading date was negatively correlated with yield. NDVI values decreased over the course of the growing season. The mean values of the DH lines across environments were comparable to those of the parents and checks. Importantly, stripe rust severity showed a significant negative correlation with both yield (r=–0.30 and r = –0.48, at Ridgetown and Elora, respectively) and NDVI (r=-0.58 and r=-0.24, at Elora and Ridgetown, respectively) at the ripening stage, indicating that late-season infection reduced green leaf area and lowered crop productivity.