Effects of different salt levels on germination and seedling growth of sesame (Sesamum indicum L.) cultivars

Sesame (Sesamum indicum L.) is rated as moderately salt tolerant and it can produce profitable crops on saline soils. Salinity reduces germination and delays emergence and sesame stands tend to be irregular and crop yield is depressed. However, some cultivars are less affected by salinity than others. In this study, we aimed to determine the effects of salinity levels (0, 0.08, 0.16, 0.24 and 0.32 ds.m-1) on germination and seedling growth of three sesame cultivars (Ahvaz, Mobarake and Shiraz). Germination rate, root and shoot length, root and shoot dry weight and germination percentage were determined. On average, Mobarake gave the highest germination percentage and root length, while Shiraz showed the lowest value for germination percentage, root length, shoot length, shoot dry weight, root dry weight and germination rate. As salinity levels increased, germination percentage, root length, shoot length, shoot dry weight and germination rate decreased. At the highest salinity levels, Mobarake had the highest germination rate, root length, shoot length, root dry weight, shoot dry weight and germination percentage, while Ahvaz and Shiraz only had the shoot length and shoot dry weight at 0 and 0.08 ds.m-1. There was no significant difference between the cultivars up to 0.16 ds.m-1 salinity levels, however, there were significant differences between the cultivars beyond this salinity levels. Information on the response of seed germination and seedling growth to salinity for sesame in different environments so far. Differences in salt tolerance among cultivars indicating that selection within cultivars could be possible for more salt tolerant cultivars at germination stage. Mobarake had the highest tolerance against salinity, and may performed better at germination stage under salty soils.