Importance of Priming Application Times on Growth, Relative Water Content and Photosynthetic Pigments of Rapeseed (Brassica napus ssp. oleifera L.) Cultivars Under Salinity Stress

Environmental stress factors affect plant production more and more every day. One of these stress factors is salinity. The use of biostimulants is increasing day by day and gaining importance in order to reduce the effects of stress factors and increase the yield and quality in plant production. Chitosan (Ch) is one of the biostimulants whose use in agriculture is increasing day by day. Seeds of rapeseed cultivars were used in this study, and it is an important oil plant. In this study, the times of priming applications with Ch (3 times) [0 (control) (Ch1), 12 hour (Ch2), 24 hour (Ch3)] and different doses of salt stress (S) [0 (control) (S1), 50 mM L-1 (S2), 100mM L-1 (S3)] in rapeseed cultivars (NK Caravel (C1), Elvis (C2), Champlain (C3) under laboratory conditions were investigated. Germination percentage (GP), seedling length (SL), root length (RL), seedling fresh weight (SFW), root fresh weight (RFW), relative water content (RWC), total chlorophyll (Total Chl), carotenoid (Crt) parameters were examined. As a result of the research, with Ch applications, GP (84.67% to 86.67), SL (7.83 cm to 8.12), RL (6.42 cm to 6.50), SFW (0.10 g to 0.53), RFW ( 0.02 g to 0.06), RWC (62.84% to 63.30), Total Chl (1.60 mg g-1 to 1.90), and Crt (1.60 mg g-1 to 1.89) has increased. It has been determined that Ch application times play an important role in reducing salt stress in the investigated parameters.