The Dynamic Change Of Some Senescence Associated Indexes In Different Nutrition Modes

Plant senescence is a complex physiological and biochemical process. this question have been studied for many years to discover the molecular mechanism. Especially, if people make the mechanism sever for mankind in agriculture ,it can extend the yields and the periods of the storage of crops and fruits. So the experiment was developed to gain high yield and quality of the wheat. First We sampled the wheat flag leaf in different cultural modes from anthesis 15 days to 32 days. Then, we measured chlorophyll content , POD activity, SOD activity and protease activity which have a closely relation with leaf senescence. The main results are as follows: 1. The index associated senescence has the same change rule in flag leaf and the second leaf. 2. The result of POD activity showed: Improving POD activity can accelerate the degradation of Chl in the late senescence period. The result in fields indicates that increasing fertilizer improved leaf drought-resistance capability and wheat output after comparison between two nitrogen rate. 3. We have found the senescence leaves have only two bands of the isozymes of superoxide dismutast (SOD) by PAGE. The band with smaller molecular weight has a higher content and 4. Improving the content of Nitrogen is helpful to increase Chl content ,the activity and function time of SOD and Protease. That showed Improving the content of Nitrogen can delay leaf senescence, improve the wheat yield and quality. 5. It is considered that FM(N8) treatment can effectively delay leaf senescence, also it's propitious to nutrition retreatment after comparison among all treatments. 6. After the analysis on the mRNA 3'-UTR of the wheat plasma membrane intrinsic protein(PIP), a fragment about 280bp were cloned . It will be made into probe afer sequencing. And we'll found a method about Northern Blot which can be used to check the the transcription of mRNA. 7. The result in room indicated: Increasing fertilizer could improve leaf RWC under sufficient water condition; Under water stress, increasing fertilizer have little function to leaf RWC. The another result was: phosphorus application is important to water absorptance of drought-resistance wheat. Increasing fertilizer always improved chl content which lies on nitrogen application.