Studies On The Regulation Of S-3307 Applied To Seeds On Germination And Strong Seedling Of Wheat

The effects of S-3307 (Uniconazole) applied to seeds with different concentrations (0, 5, 10,20, 40mg/kg) on seeds germination and strong seedlings of wheat c.v. (Mianyan26)were studied. The results were showed as follows:1.S-3307 treatments accelerated the root occurrence, the number of roots for S-3307 treatments in mianyan26 was significantly more than that of control, the higher the concentrations, the more of the number of root, the number of roots for S-3307 treatments entranced high maintain period earlier 1 day than the control. S-3307 treatments inhibited Plumule occurrence, the time of entrance to high maintain was later 1 day than the control. S-3307 treatments decreased, however enhanced the rate of seed germination and made the seed germination line.2.S-3307 treatments were able to promote the speed of wheat DNA synthesis, furthermore, different of S-3307 concentrations were able to induce an unscheduled DNA synthesis in seed embryos of wheat in different level. When the concentration of S-3307 was 20mg/kg, the speed of wheat DNA synthesis was quickest. At the same time, the incorporating 3H-TdR reflected DNA repairing and coping in the early period of wheat seeds germination.3.S-3307 treatments decreased then enhanced GA,ABA contents on endosperm during seed germination and ZT, IAA contents were not significant than that of control; S-3307 treatments decreased GA, IAA contents on plumule and enhanced ZT,ABA contents; S-3307 treatments decreased enhanced GA,ZT,IAA contents on radicle during seed germination and ABA content was lower than control during beginning germination then was higher during later germination.4. S-3307 treatments delayed carbohydrate degradation, inhibited a -diastase on endosperm during wheat seed germination, and S-3307 treatments prolonged starch degradation. At the same time, S-3307 treatments enhanced the active of protease diastase during wheat seed germination and accelerated the speeds of nitrogen47decompose, S-3307 treatments also caused the accumulation speeds of soluble protein, which was good to construction of cell.5. S-3307 treatments increased the chlorophyll and soluble protein contents in the leaves during wheat seedling (before three leaf), and increased chlorophyll a/b ratio. It's benificial for wheat seedling absorbing photosynthety, enhancing photosynthetic rate of leaf and accumulating matter, all of these were the physiological basis of high yield.6.Lower S-3307 treatments enhanced on root active of wheat seedling, higher S-3307 treatments inhibited, and the concentration 20mg/kg was best .At the same time, S-3307 treatments increased the accumulate of soluble sugar. nitrogen content and sugar nitrogen ratio. All of these improved the inner enviroment of the root. And the seedlings in S-3307 treatments showed an appearance of strong root with increase of root number and root thickness.Therefore, it was suggested that the action of S-3307 on seed germination of wheat were improved endogenous hormones balance and carbon and nitrogen metabolis. During the seedling stage, the action of S-3307 on chloroplast ultrastructure increased content of chlorophyll, enhanced use efficiency of solar energy. The physiological mechanisms of S-3307 to improved photosynthetic and the rate of carbodrate accumulating, so that it enhanced photosynthesis and absorbing to root nutriment.