Marker assisted introgression of bacterial blight resistance in Samba Mahsuri, an elite indica rice variety

Abstract

Samba Mahsuri (BPT5204) is a medium slender grain indica rice variety that is very popular with farmers and consumers across India because of its high yield and excellent cooking quality. However, the variety is susceptible to several diseases and pests, including bacterial blight (BB). We have used PCR based molecular markers in a backcross-breeding program to introgress three major BB resistance genes (Xa21, xa13 and xa5) into Samba Mahsuri from a donor line (SS1113) in which all the three genes are present in a homozygous condition. At each backcross generation, markers closely linked to the three genes were used to select plants possessing these resistance genes (foreground selection) and microsatellite markers polymorphic between donor and recurrent parent were used to select plants that have maximum contribution from the recurrent parent genome (background selection). A selected BC 4 F 1 plant was selfed to generate homozygous BC 4 F 2 plants with different combinations of BB resistance genes. The three-gene pyramid and twogene pyramid lines exhibited high levels of resistance against the BB pathogen. Under conditions of BB infection, the three-gene pyramid lines exhibited a significant yield advantage over Samba Mahsuri. Most importantly, these lines retain the excellent grain and cooking qualities of Samba Mahsuri without compromising the yield as determined in multi-location trials. This work demonstrates the successful application of marker-assisted selection for targeted introgression of multiple resistance genes into a premium quality rice variety.

Multi-Location Evaluation of Gene Pyramided Lines of Mtu 1010 and JGL 1798 against Bacterial Blight of Rice

“…Pyramiding multiple resistance genes for different biotic stresses provides in-built resistance to the popular and widely adopted cultivars and thereby reduces the yield loss due to biotic stresses. A number of research laboratories are carrying out gene pyramiding program by introgressing multiple BB resistance genes in popular rice varieties to provide in-built resistance against this disease (Sundaram et al, 2008;2009;Salgotra et al, 2012;Hajira et al, 2014;Ellur et al, 2016a;Ellur et al, 2016b). In this study, two broadspectrum BB resistance genes, Xa21 and xa13 were pyramided in two popular rice varieties, MTU 1010 and JGL 1798 to provide in-built BB resistance.…”

Past, present and future of rice blast management

“…Another variety of rice resistant to bacterial blight was developed in non basmati type rice in India by using MAS. PCR based molecular markers were used in a backcross breeding program to introgress three major bacterial blight resistance genes (Xa21, Xa13 and Xa5) into Samba Mashuri from a donor line (SS1113) in which all the three genes are present in a homozygous condition (Sundaram et al, 2008). These two reports successfully demonstrate the application of MAS to control the pathogens.…”

Markers Assisted Selection for Pyramiding of Gallmidge Resistance Genes in Kavya, a Popular Rice Variety

“…Genes leading to different races or biotypes being resistant to a disease or insect pest can be effectively pyramided using tightly linked molecular markers to develop lines with multi-race or multi-biotype resistances (Sundaram, et al, 2008;Rajapurohit, et al, 2010;Divya, et al, 2015 andPradhan, et al, 2015). These multi-race or multi-biotype resistant genotypes proved to be more durable than any single-race or single-biotype resistance.…”