The Study Of Traits And Genes Related To Leaf Senescence After Flowering Of Rice Responding To Tiller And Panicle Nitrogen Feitilizer

The leaf of rice is one of the important organ for photosynthesis,grain-filling carbohydrates needed for most come from the photosynthesis after heading,so the leaf lifespan or the organizational structure and so on directly affect the photosynthetic efficiency and the product quantity,and then influence crop grain yield and quality.Reasonable fertilization can not only prolong leaf life,increase photosynthetic products,improve rice yield and quality,but also improve nitrogen utilization rate and reduce ecological environmental pollution.Tillering fertilizer and panicle fertilizer are important controling measure to control rice population structure,yield and quality.So,understanding after rice floral leaf senescence associated genes and other physiological indexes for different tillers panicle fertilizer genetic response,to clarify molecular regulation mechanism of rice leaf senescence after flowering,and increase the yield and quality has important theoretical and practical significance.In this study choose the cold area panicle weigth type super rice Songjing 9 and spike number type high yield variety Longdao 11,under potted condition of rice varieties tested grouting mature leaf senescence related compounds,enzyme activity and gene transcription expression quantity and yield and quality traits of different tillers spike fertilizer response results,and carries on the correlation analysis.The results of the study are as following:The results of this study indicate that the total grain number,1000-grain weight and seed setting rate of panicle heavy variety Songjing 9 have a strong reaction to the increase of panicle fertilizer,which is manifested as increasing,and thus increasing the grain weight of a single plant.In contrast,the panicle number variety Longdao 11 responded more strongly to tillering fertilizer,increasing the number of effective panicles significantly and increasing the grain weight of a single plant.Two types of varieties of rice the rice quality characters have similar response to panicle and tiller fertilizer ratio,The higher the proportion of panicle fertilizer,PKV,HPV,CPV,BDV and taste value decreased,while,SBV,CSV,protein and amylase content rise,increased panicle fertilizer not good for improving rice quality adverse to improve rice quality.At grouting maturity period,the content of soil total N,NH4⁺-N,NO₃^--N,response to panicle tillering fertilizer is with the increase of panicle fertilizer,the decrease rate of soil nitrogen was significantly delayed,Keep the soil well supplied with nitrogen for a long time.At grouting maturity period,the inclusions of leaf response for the panicle tillers fertilizer ratio,leaf total nitrogen and chlorophyll content increased with the increase of panicle fertilizer application,performance in each time period for the T1>T2>T3>T4,and soluble sugar content and the performance of the carbon nitrogen ratio,by contrast,are characterized by T4 in each periods of time>T3>T2>T1.Two varieties of soluble sugar content of tillers spike fertilizer response differences,panicle heavy type variety Songjing 9,the soluble sugar content increased first and then decreased showed the single peak curve,while panicle number type variety Longdao11 showed slowly decreased curve.Illustrate the variety of different types during earing grouting to spike tillers fertilizer ratio response differences,should be appropriate adjustments according to the characteristics of different types.At grouting maturity period,the leaf photosynthesis response to the spike tillers fertilizer ratio,with applying panicle fertilizer content is higher,significantly increase photosynthesis speed limit Rubisco enzyme gene family each gene expression,and significantly prolonged the time of high expression,two varieties OsRBCL and OsRBCS4 gene expression of genes have been rising after falling single curve trend,two varieties OsRBCL genes and OsRBCS4 gene expression peak appeared in 15d after heading,OsRBCS2 and OsRBCS3 gene expression quality showed a trend of gradual decline.The photosynthetic response was more significant to the increase of nitrogen application in panicle fertilizer.At grouting maturity period,the response of antioxidant enzyme activity and MDA content in leaves to tillering panicle fertilizer ratio was as follows:with the increase of nitrogen fertilizer application,antioxidant enzyme SOD and POD activity were significantly increased,and MDA content was decreased.The activity of SOD and POD of the two tested varieties was T1>T2>T3>T4.In contrast,MDA content changes as T4>T3>T2>T1 during the whole grouting process.Leaves in the process of grouting,two varieties tested cysteine protease gene transcriptional expression quantity have been increased after reducing single curve changes,between these two varieties,panicle type variety Longdao 11 peak time appeared earlier about 5d contrast panicle heavy variety Songjing 9,With the decrease of nitrogen application in tiller fertilizer and the increase of nitrogen application in panicle fertilizer,the transcription expression of cysteine protease gene was decreased.