Estimating genetic variation and genetic parameters for grain iron, zinc and protein concentrations in bread wheat genotypes grown in Iran

The low grain micronutrient concentrations particularly iron and zinc are well documented problems in wheat. Eighty bread wheat genotypes were assessed for grain iron (GFeC), zinc (GZnC) and protein (GPC) concentrations along with agronomic traits for two consecutive years under normal and terminal drought stress conditions within each year. The results of combined ANOVA revealed high significant genotypic variations for GFeC, GZnC and GPC as well as agronomic traits under both conditions. The genotype x year interaction was significant for thousand kernel weight (TIM) and GPC under normal and for TIM/under drought stress conditions. According to average of both years, drought stress caused reduction in kernel yield (KY) and its components, while raising trends in GFeC, GZnC and GPC were observed. In all environments, KY had negative phenotypic and genotypic correlations with GFeC, GZnC and GPC. Broad sense heritability of GZnC, GFeC and GPC were observed as moderate to high under normal conditions across two years. Cluster analysis showed that the older genotypes and landraces were located on a separate cluster with high GFeC, GZnC and GPC and low KY. Finally, the two extreme groups of genotypes were identified in order to be used as parent in crossing programs. (C) 2018 Elsevier Ltd. All rights reserved.