Integrating marker-assisted selection and doubled haploidy for rapid introgression of semi-dwarfing and blast resistance genes into a Basmati rice variety ‘Ranbir Basmati’

Abstract

Ranbir Basmati, an early maturing pure line selection of traditional Basmati 370, is widely cultivated Basmati variety in the Indian state of Jammu and Kashmir. The variety is tall statured, prone to lodging and highly susceptible to rice blast. The present study was carried out for genetic improvement of Ranbir Basmati for semi dwarf stature and resistance to blast by introgressing semi-dwarfing gene, sd1, and blast resistance gene, Pi9 from an improved Basmati rice variety, Pusa Basmati 1637 (PB 1637).The selfed progenies of two superior BC2F1 recombinants of the cross Ranbir Basmati/PB 1637 showing maximum recovery of recurrent parent genome and phenome were analyzed with gene-based markers to select plants homozygous for both Pi9 and sd1. These plants were processed via anther culture to produce homozygous doubled haploid (DH) lines. All the anther culture derived DH plants were short-statured compared to Ranbir Basmati and exhibited high level of resistance to blast. The analysis of yield and its component traits revealed the presence of superior transgressive segregants for various traits namely, effective tillers, grains per panicle and yield per plant. Combined use of marker-assisted selection and anther culture ensured speedy conversion of Ranbir Basmati into semi-dwarf genotypes with in-built resistance to rice blast. The study demonstrated the utility of anther culture as an adjunct to marker-assisted backcross breeding schemes for instant elimination of the residual background heterozygosity of the selected recombinants.