Transcription profiling of parental lines and bulked salt sensitive and salt tolerant RILs derived from 2 rice varieties

The aim of this study was to minimize the number of candidate genes responsible for salt tolerance between a pair of rice varieties (CSR27 and MI48) with contrasting level of salt tolerance by bulked segregant analysis of their recombinant inbred lines. Microarray analysis of RNA extracted from the tolerant and susceptible parents without and with stress showed 798 and 2407 differentially expressed genes, respectively. The number of differentially expressed genes was drastically reduced to 70 and 30, by pooling the RNAs from ten extreme tolerant and ten extreme susceptible RILs due to normalization of irrelevant differentially expressed genes between the parents. RNA from CSR27, MI48, tolerant bulk and susceptible bulk grown under control and salt stress conditions were analysed in two different biological replications (A and B) making total sixteen samples