Impact of seed priming with different UV rays on morphological and physio-biochemical attributes of pea (Pisum sativum L.)

In order to investigate the effect of priming and UV stress on pea (Pisum sativum L. cv. Dorian), a pot experiment was conducted as factorial based on completely randomized design with 22 treatments (11 type of seed priming and 2 UV stress conditions) and four replications at Razi University during 2014. The results showed that the impact of seed pre-treatment was significant on all traits studied. Also, effect of UV stress was significant on relative water content (RWC), maximum quantum yield of PSII, total chlorophyll (Chl total) content and hydrogen peroxide concentration (H2O2). Interaction between seed priming and UV stress was also significant (p≤ 0.01) for RWC, Chl total content and H2O2 concentration. Generally, the results indicated that UV stress has harmful effect on the pea plants. On the other hand, hydro-priming (HP) had a better effect on the morphological characteristics (stem length and fresh weight) and RWC, especially, under non-UV stress condition. But, HP for 12 h + UV-AB for 2 h and also HP for 11 h + UV-AB for 3 h showed the lowest Chl total content, maximum quantum yield of PSII, stem length and fresh weight of plant and also had the highest concentration of H2O2. Therefore, these two pre-treatments have a negative impact on the pea plant and their use is not recommended for the pre-treatment of seeds in pea.