Baseline status and effect of genotype, environment and genotype x environment interactions on iron and zinc content in Indian chickpeas (Cicer arietinumL.)

Genetic biofortification is a cost-effective strategy to address iron (Fe) and zinc (Zn) deficiencies prevalent worldwide. Being a rich and cheap protein source, chickpea, a food legume grown and consumed across the globe, is a good target for biofortification. Nineteen popular commercial cultivars of India were analysed for Fe and Zn content at four locations representing different agro-climatic zones to study the genotypic and genotype x environment interactions on Fe and Zn. Distribution of phytic acid (PA), an important anti-nutrient that chelates and reduces the mineral bioavailability, was also analysed. Influence of other agronomic traits like days to flowering, plant height and 100 seed weight on Fe and Zn content was also studied. All the traits showed significant G and G x E interactions; however, the magnitude of variance of GXE was lesser than that of G alone. Genotype + genotype-by-environment and genotype-by-trait biplots were used to assess the relations between different environments, genotypes and traits. Iron and zinc content showed positive correlation between them indicating a possibility of their co-selection in breeding. A negative correlation between Zn and PA was observed. However, there was very low variability for PA content in the cultivars under study, indicating that moderate PA is naturally selected in these cultivars during breeding. Despite significant GXE interactions, cultivars with high Fe (> 70 mu g/g) and Zn content (> 40 mu g/g) at three out of four test locations were identified. Such genotypes will be useful in breeding programs for enhancing mineral micronutrient content and understanding the molecular mechanisms governing their differential uptake.