Localization and gene action studies for kernel iron and zinc concentration in groundnut (Arachis hypogaea L.)

Iron (Fe) and zinc (Zn) are important micronutrients for human health and well-being. Groundnut kernels are good sources of Fe and Zn. Localization studies of Fe and Zn in the kernel tissues of ten diverse groundnut genotypes revealed that, cotyledons contribute nearly 85–90% of total Fe and Zn in comparison to seed coat and embryo on dry matter basis. Generation mean analysis revealed the predominant role of additive gene action for kernel Fe and Zn concentration in the cross ICGV 06,040 × ICGV 87,141, and both additive and additive × additive interaction in the cross ICGV 06,099 × ICGV 93,468. Duplicate epistasis was observed for kernel Fe and Zn concentrations in both the crosses. For yield parameters, pod yield per plant and 100-kernel weight, dominance gene action was significant. Additive × additive interaction was also found to be significant for these traits which can be fixed through selection. For days to maturity, additive, dominance, additive × additive and dominance × dominance interactions were significant. The study involved six generations of two crosses involving parents with contrasting kernel Fe and Zn concentrations and was conducted for five economically important traits using a six-parameter model. There was significant positive association between kernel Fe and Zn concentration in both the crosses indicating possibility of simultaneous improvement. Absence of association of kernel Fe and Zn concentration with pod yield per plant will enable the development of high pod-yielding varieties with elevated levels of kernel Fe and Zn concentration.