ارزیابی تحمل ژنوتیپ‌های مختلف برنج به شوری آب آبیاری

To study the responses of seven rice genotypes (Khazar, SA13, Deylam, Sange Joe, Sepidrud, 831 and T5) to different levels of irrigation water salinity, and determining grain yield based on tolerance indices, a CRD based factorial pot experiment with five levels of irrigation water salinity (1, 2, 4, 6 and 8 dSm-1) and three replications was carried out at Rice Research Institute of Iran in 2011. Indices such as SSI, TOL, MP, GMP, HM, STI, YI and YSI were calculated and their correlations with grain yield were estimated for both stress and non-stress conditions. Results indicated significant differences among genotypes and the indices within both conditions. Results also showed that STI and MP indices could be considered as the best indices to screen salt tolerant genotypes. Among the genotypes used in the experiment, T5 produced the highest yield in both non-stress (19.71 g/plant) and stress (10.69 g/plant) conditions, while the lowest yield in normal (11.84 g/plant) and stressful (4.29 g/plant) conditions was recorded for Deylam and Khazar, respectively. The highest and the lowest percentage of yield reduction were found in Khazar (69.49%) and Sange Joe (31.48%) in stressful conditions, respectively. Overall, genotypes T5, 831, Sepidrud and Sange Joe can probably be considered as superior high yielding genotypes in both saline and non-saline conditions for further research.