The effect of different priming treatments on germination of sesame (Sesamum indicum L.) seeds under drought stress

摘要

The objectives of this research were to evaluate the effects of priming on germination and plant growth characteristics of sesame, experimental design was factorial with complete randomized design as base design with 4 replications. The first factor waspriming by PEG 6000 (-0.4Mpa), KN03 (2%), NaCl (0.5 mM), CaC12 (2%) GA (50 ppm) and water for 24 h at 20±1°C and secondary factor was combinations 6 levels of stress (0, -0.2, -0.4, -0.6, -0.8 and -1 Mpa) and tertiary factor was two cultivars (Oltan and Ts-3). The results indicated that priming, drought, cultivar and interaction effects on all traits such as germination percentage (GP), root length (RL), shoot length (SL), seedling fresh weight (SFW), seed dry weight (SDW) and germination rate (GR) were significant. Results also showed that priming on plant height and plant dry weight were significant p<0.05 and on plant fresh weight non-significant. The effect of drought stress on plant height and plant dry weight were significant at 1% and 5% probability level, respectively and on plant fresh weight non-significant. The effect of cultivar on plant height was significant (p<0.05) and on plant fresh weight and plant dry weight non-significant. Interaction effects of priming and stress on plant height were significant (p<0.05) and on plant fresh weight and plant dry weight non-significant (Table 8), also other interaction effects on all traits was non-significant. From the following results indicated that measured germination and plant growth characteristics were declined with drought stress in both cultivars, but this reduction was greater for Oltan cv as compared to Ts-3 and also results showed that priming treatments increases germination characteristics and plant growth under drought stress forboth cultivars. In the final results indicated that priming with KN03 had a greater all traits than unprimed and other priming treatments, thus the best priming treatment under drought stress conditions was primed by KN03.