Marker-Assisted Introgression of Saltol QTL to enhances seedling stage salt tolerance in cytoplasmic male sterile background of rice

Abstract

Rice is a most salt sensitive cereal crop with a threshold of 3 dSm1 for most cultivated varieties and it is one of the major obstacles to increase rice production worldwide. Hybrid rice offers a wide opportunity to improve rice productivity in India. Hybrid rice has the potential to increase yields by 15% to 20% over those of conventionally bred varieties (Virmani, 1994). Most popular CMS sources of rice hybrids also sensitive to salinity. Here, we studied single sequence repeat polymorphism in between a highly salt tolerant line FL478 and widely adopted salt sensitive CMS source IR58025B for Saltol QTL located at chromosome No.1. Saltol QTL linked 50 markers served for targeted QTL with both lines and ten foreground markers found polymorphic between rice cytoplasmic male sterile maintainer 58025B and Saltol QTL donor FL478 at targeted Saltol QTL region on chromosome. These identified polymorphic markers are served on F2 population of IR58025BXFL478 to recover the targeted Saltol QTL on chr.-.1 for identification of maintainability, Rf marker RM6100 used to avoid the restorer plants and selected plants utilized to develop homogenous maintainer population.