Development of early maturing Pigeonpea lines through induced mutagenesis

Abstract:

Nearly 85% of the world's pigeonpea is grown in India, yet average national productivity has stagnated around 780 kg/ha — partly because most cultivated genotypes take 160-200 days to mature, limiting their fit in intensive cereal-based rotations. This research used induced mutagenesis to develop early maturing pigeonpea lines from two parent cultivars, Pusa 992 and UPAS 120. Seeds were treated with ethyl methanesulfonate (EMS) at 0.2%, 0.4%, and 0.6% concentrations and gamma radiation at 200, 300, and 400 Gy doses. Mutant populations were advanced through four generations (M₁ to M₄) at Pantnagar, Uttarakhand, during 2019-2022. Of 2,174 M₂ plants screened, 28.3% exhibited early flowering (less than 90 days after sowing). By M₄, seven stable mutant lines flowered 23-38 days earlier than their parents while retaining acceptable seed weight and yield. The line PM-EMS-4-17 combined the earliest maturity (118 days) with a grain yield of 1,463 kg/ha, exceeding the UPAS 120 parent by 18.7%. EMS at 0.4% proved the most effective mutagen for generating desirable variation. These findings point to a viable path for incorporating early maturity into pigeonpea improvement programmes targeting short-duration cropping windows.