Effects Of Warming And Fertilizing Methods On Seedling Gowth And Physiological And Biochemical Indexes Of Tobacco

This paper studies the effects of warming and fertilizing methods on seedling biological traits and physiological and biochemical indexes of tobacco. Main research results obtained are as follows1. The floating seedling test results in using different ways of warming showed that increasing environmental temperature was beneficial to the growth of tobacco seedlings. Among them, by heating water temperature and shed temperature processing, leaf width, stem circumference, above-ground fresh weight, root fresh weight of floating seedling significantly were greater than sealed sheds treatment and no-heating treatment, the difference was significant (P<0.01). From the point of physiological and biochemical indexes, the way of heating water temperature and shed-air temperature can improve the seedling root system vigor, increase chlorophyll content in tobacco leaves and reduce tobacco seedling proline content.2. Test results showed that seedling stage significantly be prolonged in fertilizating once compared with two times and three times, It was better that the first time of fertilization was in the period of two cotyledons flatting. Increasing the times of fertilization can thicken seedling stem girth obviously, but there was not significant difference between the same treatments of fertilization times. With the increase of the fertilization times, the root activity of tobacco seedling improved greatly and the chlorophyll content in leaves increased correspondingly. The two time interval for15days of fertilization, fertilization3times’7leaves and one-heart stage tobacco seedling, nitrate reductase activity was35%higher than that of fertilization1times. Compared tobacco seedlings of fertilization three times in5-leaf-1-heart,6-leaf-1-heart and7-leaf-1-heart, the reducing sugar content respectively was8.1%,9.6%,15.3%higher than that of fertilization one time. And the reducing sugar content showed no obvious difference between the diffirent treatments with the same times of fertilization. The results of the tobacco seedling invertase experiment with diffirent treatments of fertilization showed that in the period of4-leaf-1-heart,5-leaf-1-heart and6-leaf-1-heart, the activity of invertase in the one time fertilization was obviously lower than the other treatments. In7-leaf-1-heart stage, the level of invertase activity among the three groups with the diffirent fertilization time treatments showed significantly diffirences.3. The research results of different fertilization amount showed that in the7-leaf-l-heart stage, stem girth, above-ground fresh weight and root activity of tobacco seedling with fertilization1000mg/L was the highest. The underground fresh weight and root/shoot ratio were best for fertilization1500mg/L. And the chlorophyll content was highest fertilization1250mg/L. Besides, the nitrate reductase activity in tobacco leaf improves with the increasing of the fertilization amount. However, when the fertilization amount exceeds1500mg/L, the activity of nitrate reductase reduces instead. Combining the research results of physiological and biochemical indexes, the author thinks that the fertilization1250mg/L was the most benefit to the growth and development of tobacoo seedling.