Validation and association analysis of microsatellite markers related to drought and salinity tolerance in Aerobic and Iranian rice under osmotic stress

The present study was conducted to validate microsatellite markers associated with drought tolerance in rice, in the natural population, including foreign varieties, aerobic rice and Iranian varieties. Plant material under normal and two levels of osmotic stress (-8 and -16 bar using of mannitol) were evaluated by standard germination test in terms of 14 traits. Genotyping was done using 26 pairs of microsatellite markers on 53 genotypes of rice. The results of the structure analysis showed the number of clusters that maximizes ΔK parameter is three. Then association analysis was conducted using the matrix structure of the population by GLM and MLM statistical models. Two MLM models identified, 75 and 30 markers for studied traits at 5% level, respectively. The markers RM11943, RM104, RM190, RM28166, RM231, RM510, RM270, RM19367 and RM431 were identified as markers associated with tolerance to osmotic stress with explain variation of several germination traits. Also the results indicated RM270 with 40.4% of the seed vigor, RM276 with explain variation of 33.9% of the percentage of water content of the seedling, and RM523 with explain variation of 40.6% and 30.7% of the speed of germination coefficient, had highest of coefficient of determination under stress relatively to other markers. That could be a reason for conformation of their relationship with germination traits under osmotic stress. Considering of the obtained results, after verification of results in the other genetic backgrounds we can use these markers in the breeding programs.