Development of Basmati rice genotypes with resistance to both bacterial blight and blast diseases using marker assisted restricted backcross breeding

Abstract

Marker assisted backcross breeding (MABB) is aimed at introgression of trait(s) into a popular variety to augment specific trait(s) in an otherwise popular variety. While MABB can improve a variety with respect to introgressed trait(s), it offers very little scope for improvement of other traits. Marker assisted restricted backcross breeding (MARBB) is an alternative which can help in identifying transgressive segregants especially, when the donor parent is an elite genotype with several desirable traits. In the present study, restricted backcrossing followed by pedigree selection was used for the development of improved genotypes of Basmati rice with BB and blast diseases using an early maturing Basmati rice variety, Pusa Basmati 1509 as recurrent parent and an elite restorer line, Pusa 1790 as donor. Foreground selection for xa13, Xa21, Pi2 and Pi54 in the backcross progenies was combined with phenotypic selection for agronomic and grain quality traits to ensure premium Basmati grain quality in the progenies. Multilocation yield trial was conducted to evaluate the performance of the improved Basmati rice genotypes with both BB and blast resistance. Pusa 1847-12-62-115-20-6 and Pusa 1847-12-62-190-39-7 recorded significantly higher yields of 68.88 and 62.44 q/ha, respectively, compared to PB 1509 (57.88 q/ha). The improved progenies exhibited resistance to BB with an average lesion length of 2 cm, and blast with scores between 0–2, while PB 1509 was highly susceptible. Another genotype, Pusa 1847-12-62-37-8-3 exhibited head rice recovery (HRR) of 63.99%, which was significantly higher than in PB 1509 (56.40%). Marker assisted selection was also effected for fertility restoration genes and improved grain quality traits based on which two improved Basmati rice genotypes pyramided with BB and blast resistance namely, Pusa 1847-12-62-115-20-6 and Pusa 1847-12-62-190-39-7 were found promising, along with improved grain and cooking quality as well as restoration potential, which could be used in breeding better quality hybrids.