Osmo- and hydropriming enhance germination rate and reduce thermal time requirement of pea (Pisum sativum L. cv. Winner) seeds

Authors : Erdal ELKOCA

Pages : 1-12

View : 27 | Download : 35

Publication Date : 2015-03-01

Article Type : Research Paper

Abstract :The effects of various seed priming treatments and seed soaking durations on germination performance of pea (Pisum sativum L. cv. Winner) seeds were examined. Seeds were osmoprimed in polyethylene glycol (PEG 6000) (-0.5, -1.0 and -1.5 bar) or in mannitol (1%, 2% and 3%) and hydroprimed with water for 12 or 24 h at 25 ± 0.5 °C in darkness. Primed seeds were subjected to germination tests at ten different constant temperatures ranging from 5 to 32 ± 0.5 °C. Priming treatments had no significant effect on germination percentage. But, osmo- and hydroprimig treatments improved germination rate and decreased thermal time requirements significantly and induced more synchronous germination at some of the temperatures tested. Reductions in thermal time requirements ranged between 3.4 °C d and 11.3 °C d, 6.6 °C d and 17.4 °C d, and 11.6 °C d and 27.5 °C d for 10%, 50% and 90% germination, respectively. As compared with the priming duration of 12 h, priming duration of 24 h had generally negative effect on the 50% germination time and thermal time requirement. Among the osmopriming treatments, seeds treated with -0.5 bar solution of PEG and 1% solution of mannitol, and also hyropriming gave the best results. Consequently, above osmo- and hydropriming treatments for 12 h might be recommended for better germination of pea.
Keywords : Germination rate, germination synchrony, mannitol, polyethylene glycol PEG, thermal time requirement