Diversity in Selected Grain Mineral and Protein among Pigeonpea Landraces

Pigeonpea (Cajanus cajan) is an important grain legume that provides highly nutritious food for human consumption. It contains high amounts of protein, carbohydrates, fats as well as both macro- and micronutrients. This study examined the genetic diversity of grain mineral and protein content among fourteen pigeonpea landraces. There were highly significant differences (p ≤ 0.001) among the landraces for most of the mineral elements including calcium (Ca), copper (Cu), potassium (K), magnesium (Mg), manganese (Mn), phosphorus (P) and zinc (Zn). The K and P content ranged from 8874.21 to 15,817.38 mg/kg and 2899.23 to 4945.12 mg/kg, respectively. Relatively high amounts of Ca (2103.43 mg/kg) and Mn (73.11 mg/kg) were observed in ‘G-03’, but ‘G-09’ attained the highest content of K (15,817.38 mg/kg) and Zn (38.56 mg/kg). Highly significant (p ≤ 0.001) negative correlations were observed between Mn and Cu. The principal component analysis showed that three landraces (‘G-03’, ‘G-04’ and ‘G-05’) were highly associated with Ca, P, Mg and Mn. The three landraces (‘G-03’ for Ca and Mn; ‘G-04’ for Mg and P; ‘G-09’ for Cu, K and Zn) possessing high grain mineral and protein (‘G-10’) contents can be utilized in pigeonpea breeding programs that are aimed at improving the grain’s traits.