Effects Of Priming Treatment With Polyethylene Glycol (PEG) And Vermiculite On The Seed Germination And Seedling Growth Of Non-heading Chinese Cabbage

With continuous improving of the level of national vegetables production, labor costs are getting higher and higher, therefore, scale, mechanization, labor-saving cultivation is the future development direction of vegetable cultivation. Precision cultivation require quality of seeds. Priming treatment can improve the seed vigor, such as the seed of priming can get a higher seedling rate in high temperature summer or winter. Priming technology is necessary to seed treatment of precision cultivation.Many studies have shown that seed priming can effectively improve the seed vigor and production characteristics of lots of vegetables and crops. There are a great quantity of seed priming ways, most of which need expensive materials, complicated steps. Priming treatment with vermiculite has advantages of low cost, easy to obtain, insoluble in water, porosity and large surface area and low water potential. Effects of priming treatment with vermiculite on the seed germination and seedling growth of non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino) that is not any domestic study.The best concentration of priming treatment was obtained by comparing with effects of priming treatment with vermiculite and PEG on the seed vigor. And then studies were carried on about the effects of priming treatment with vermiculite and PEG on the germination characteristics, the changes of the vitality of seeds and physiological characters of seedlings under low and high temperature stress.The seeds of three non-heading Chinese cabbage cultivars ’Xin Xia qing number two’,’Xia Dong qing’, and ’Hua Wang’ were used as experimental materials, and the effects of priming treatment with vermiculite and PEG on the seed germination and physiological characters of seedlings were studied under different temperatures. The results showed that after priming treatment germination rate, germination vigor, germination index, vigor index of seeds, and the fresh and dry weights of seedlings were higher than those of control. The priming treatment with PEG significantly improved the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) of the seedlings but decreased the content of malondiadehyde (MDA), resulting in that the soluble protein and soluble sugar contents in the treated seedlings were significantly higher than those of control. There were some differences in priming effects among different cultivars. Therefore, it was concluded that priming treatment with vermiculite and PEG could improve both the seed vigor and stress resistance of non-heading Chinese cabbage seedlings. But priming treatment with vermiculite is easier than PEG.