Effect of salinity on growth and germination of five rice varieties cultivated in Ampara district

Abstract

Five new improved rice varieties released by Rice Research and Development Institute, Bathalagoda were screened against salt tolerance for seed germination and early seedling growth using five different salinity levels (0, 4, 8, 12, and 16 dS/m). Measurements were taken for root length, shoot length, fresh weight of seedlings, dry weight of seedlings, germination energy, speed of germination and final germination percentage. All the tested variables, except dry weight of seedlings, decreased with increasing salinity and had a significant difference (p<0.05) between salinity levels. Osmotic stress due to increasing salinity and toxic effect due to high sodium ion concentration interfere water absorption by plants and affect physiological activities in seeds and seed germination. Among the rice varieties used, Bg 357 rice variety had a higher root length, shoot length, fresh weight of seedlings, germination energy, speed of germination and final germination percentage and was considered as tolerant to salt. All the other rice varieties had different degrees of sensitivity to salinity.