Effect Of Sand Priming And Cold Resistant Pharmaceutical Treatments On The Seed Germination And Anti-cold Of Seedling In Rice(Oryza Sativa L.)

Effect of sand priming and cold resistant pharmaceutical treatments on the seed germination, seedling quality and physiological changes was investigated in four rice varieties (Jiayu 948, Zhongzu No.l, Zhenong 8010 and Zhenong 921). Effect of the two treatments on cold torelance and physiological changes was also researched at 6℃ low temperature stress. Changes of seedling quality in field after treated by sand priming and two cold resistant Pharmaceuticals were observed in Jiayu 948 and Zhongzu No.l. Main results obtained are as follows:The percentage germination, seedling root length, root score and root dry weight in the four rice varieties were significantly increased after cold resistant pharmaceutical treatments and sand priming. The energy of germination, germination index and vigor index were also improved after treated by the two treatments. There was a significant increase in shoot length of the four varieties after sand priming, however there was an increase only in one variety, Jiayu 948, after cold resistant pharmaceutical treatment C, the other were lower compared the control. It was discovered that the two treatments improved the activity of beta-amylase and alpha-amylase in rice seeds. The activity of beta-amylase was significantly increased. The content of chlorophyll and soluble sugar in rice seedlings was significantly increased after the two seed treatments. The proline content of the seedlings was significantly higher than that of two controls (direct-sowing in dry seed and direct-sowing in water imbibited seed) after sand priming. The proline content of Zhongzu No.l and Zhenong 8010 was significantly higher than that of the control (direct-sowing in water imbibited seed) after treated by cold resistant pharmaceuticals. The activity of peroxidase (POD) and catalase (CAT) in the seedling was significantly increased after the two treatments.There is a improvement trend in chlorophyll content, root score, width of basalshoot, shoot dry weight and leaf score in Jiayu 948, Zhongzu No.l after cold resistant pharmaceutical treatments in field experiment. The seedling establishment of Zhongzu Nol was significantly increased after treated by cold resistant pharmaceutical C. The soluble sugar content of two varieties significantly improved after treated by cold resistant pharmaceutical. The soluble sugar content treated by cold resistant pharmaceutical C was higher than that treated by the cold resistant pharmaceutical B in the seedling of the two varieties.It was observed that the chlorophyll content reduced after low temperature stress, then increased after recovering growth for three days in normal temperature (30℃). The increase of chlorophyll content in the two seed treatments was faster than that in the control. There was an increase in the content of proline and soluble sugar of rice seedling in low temperature stress. After recovering growth for three days in normal temperature (BOX), continuous increasing in the content of proline and soluble sugar was observed. It was discovered that the two seed treatments could improve the content increasing. The change of POD activity was similar to the content of proline and soluble sugar. The cold resistant pharmaceutical C was better than the cold resistant pharmaceutical B in anti-cold effect.