Gene expression of salt tolerance in rice (Oryza sativa L.) using gene specific markers

Abstract

The present investigation with fifty-six rice varieties/genotypes was laid out in Randomly Complete Block Design, with replicating thrice during kharif session 2018 and 2019 at the CRC of S. V. P. U. Ag& Tech. Analysis of variance revealed substantial amount of variability in the material. Through SSR analysis 1097 bands are obtained with 22 primers with an average of 49.86 band per primer which shows 100% polymorphism. Maximum band (99) was obtained by OsSOS 1 primer with amplification size of 300bp. PIC ranges from 00.00 (OsMSRMK) to 0.98 (osCAX D) with average of 0.53 and resolving power (RP) ranges from 1.00 (Os GMST1) to 3.54 (OsSOS1-1) with average of 1.80. Fifty-six genotypes were grouped into two main clusters I and II with genetic similarity of 1 and 0.73, cluster I include 1genotype and cluster II include 55 genotypes. Cluster II was further divided into two sub cluster II(a) and II(b)with genetic similarity (GS) of 0.91 and 0.95, including 3 and 52 genotypes in each cluster respectively. On the basis of visual scoring index, 9 genotypes were grouped as highly salt tolerant genotype and other 9 genotype was selected as highly salt susceptible genotype out of which 7 highly salt susceptible genotype was selected as female parent and 4 highly salt tolerant genotype was selected as male parent in the crossing programme. Crosses was made on the basis of line x tester mating design and 28 F1 are obtained, which was further crossed with their male parent to obtained BC1 population out of which two cross combination (TYPE-3 × CSR 36 and 1121 × FL 478) was found to be superior which was used for RNA expression analysis in F1BC1 population. Differential expression (2-ΔΔCt) value of 1121 × FL 478 at 6hr,12hr,18hr at 4ds\m,6ds\m and 9ds\m was found to be 4.05,8.21,0.53 which shows that value of OsSOS1-1, OsNAC 5 and OsWRKY 13 gene is up regulation at low salt concentration and down regulation at high concentrationon the other hand diffrential expression (2-ΔΔCt )value of TYPE-3 × CSR 36 at 6hr,12hr,18hr at 4ds\m,6ds\m and 9ds\m was found to be 2.23,1.73,2.83 which shows that value of OsSOS1-1, OsNAC 5 and OsWRKY 13 gene is up regulation high concentrationon.