EVALUATION OF RICE GENOTYPES IN RESPONSE TO SALINITY

Abstract

Two experiments (germination test and seedling growth for experiment 1; experiment for yield distributing characteristics and yield on pots for experiment 2) were conducted in a laboratory and shading house respectively, Department of Agronomy, Hajee Mohammad Danesh Science and Technology university (HSTU), Dinajpur during July to December 2015. For the first experiment, germination and seedling growth of 15 rice genotypes were tested in three salinity levels (0,100 and 150 mM) for 16 days in sand culture plastic pots. In the germination characters VI such as GP and GR of all rice genotypes were significantly reduced by the salt stress at 150 mM NaCl as compared to the control. The GP and GR were less affected in Joistakatari, Salna and BRRI dhan34 but Bhinipakri, Badshabhog and Kalojira were highly affected due to salinity levels under study. The study revealed that shoot and root lengths, fresh and dry weights were found to be affected due to the salinization, shoot was more affected than root. Under salinity condition longer shoot and root length were recorded in Joistakatari, Noya Paijam and Radhunipagol. In this study Joistakatari, Salna and BRRI dhan34 showed better performance in terms of root and shoot growth (fresh and dry weight) and proved to be tolerant genotypes to salinity. On the other hand Bhinipakri, Kalojira and Badshabhog were affected seriously in terms of fresh and dry weights by saline environment. After screening from experiment one Joistakatari appeared as the most salt tolerant and Bhinipakri showed the most salt sensitive genotype. On the other hand plant height, number of tiller per hill, effective tiller per hill, panicle lengths, number of grain per panicle, thousand grain weight and grain yield per plant were gradually decreased with increasing levels of salinity compared to control. Unfilled grain per panicle and noneffective tiller were increased with increasing salinity levels. It can be concluded that Joistakatari could be treated as the most salt tolerance and Bhinipakri as the most salt sensitive genotypes