Effects of NaCl induced Salinity on the Growth and Yield of Selected Rice (Oryza sativa L.) Cultivars

Abstract

Salinity induced by NaCl is one of the serious abiotic stresses that reduce plant growth, development and productivity worldwide. This experiment was conducted to assess the effects of different salinity levels (100 and 150 mM NaCl) on the growth and yield of selected rice cultivars namely, At 307 and At 308. The rice plants were grown in plastic pots (30 x 30 cm) and the experiment was laid-out in a Completely Randomized Design with six treatments and four replications. Shoot and root length, plant dry weight and yield were significantly reduced by salinity stress. At 307 showed the highest shoot length (35.6 cm) under 100 mMNaCl concentration while the lowest (21.4 cm) was found in At 308 at 150 mM salinity. The highest root length (14.9 cm) was found in At308 at 150 mM salinity and the same was lowest (6.8 cm) in At 307 at 150 mMNaCl concentration. At307 showed the highest plant dry weight (25.2 g) at 100 mM salinity and the lowest (11.5 g) was found in At308 under 150 mM salinity. Salt stress also significantly reduced the yield of tested rice cultivars. The highest yield (3.5 t h a 1) was obtained in At 307 at 100 mMNaCl concentration and the lowest (l.S th a 1) was recorded in At308 under 150 mM salinity. Based on the tested parameters, At 307 was found to grow and produce well at 100 mMNaCl concentration and At 308 did not perform well under the tested salinity levels. Hence, At 307 was identified as the salt tolerant rice genotype among the tested cultivars.