Development of advance pearl millet lines tolerant to terminal drought stress using marker-assisted selection

HHB 226 is a popular, high-yielding pearl millet hybrid cultivated widely in the Northern part of India. Drought stress at post-flowering stage is one of the major constraints in realizing potential yields of this hybrid. Developing drought-tolerant pearl millet hybrid HHB 226 is priority for pearl millet breeders. Transferring the drought-tolerant quantitative trait loci (QTLs) from donor source (863 B) to male parent of HHB 226 (HBL 11) was undertaken to improve HHB 226. The drought-tolerant donor source, 863 B was backcrossed with recurrent parent (HBL 11) up to BC3F1 generation and drought-tolerant QTLs were transferred through marker-assisted backcrossing (MABC) strategy. Four polymorphic simple sequence repeat (SSR) markers linked to drought-tolerant QTLs were used to select the plants with drought-tolerant QTLs in each generation. In BC3F1 generation, four such plants were selected. Background selection was done in BC2F1 and BC3F1 generations for recovery of recurrent parent genome. Thirty-two background markers, found polymorphic out of 64 primers screened, were further used for background selection. About 80% of recurrent parent genome has been recovered in selected plants of BC3F1 generation. The results demonstrated that drought-tolerant QTLs transferred through MAS successfully improved drought tolerance in HHB 226. © 2021, Society for Plant Research.