Study On The Activity Of Photosynthesis Enzymes And Protective Enzymes In Super High Yield Corns And Common Corns

The corn is a C₄ farm crop,in the photosynthesis process,a lot of materials participate the conversion of inorganic matter.Among them,some enzymes are all very important and have close ralationships with yield,such as PEPCase and RuBPCase.In The process of growing,plant have a perfect defending system of live oxygen clearance,so the dynamic equilibrium was set up about the live oxygen creation and clearance. The plant's protective enzymes system under the adverse circumstances include Superoxide Dismutase(SOD), Peroxidase(POD),Catalase(CAT)etc.Studing the regulations of these materials' variety and the trend of variety in the super high yield corns and common corns will have a important guide meaning to our corn production on theories and reality.In this study,we use super high yield corns xianyu 335,zhengdan 958 and common corns nongda 364,sanbei 9 as meterials,We studied the regulations of some physiological and bio-chemical index in the progress of super high yield corns.Through the research on the photosynthesis enzymes and protective enzymes in the growing progress and the mensuration of several materials in the photosynthesis and senescence progress,we work out the characteristics of enzymes' activity variety and the relation between every indexes and yield to find the rule of photosynthesis enzymes and protective enzymes' variation.The results showed that there are not obvious differences between super high yield corns' plant types and common corns'.The LAI of super high yield corns is higher than common corns',mean while,the foregoing trend line is more abrupt,more quick when rising and more even slow when descending.In filling Stage,four cultivars' max LAI are 7.23,7.07,6.89,6.45.The sequence of them is xianyu 335＞zhengdan 958＞nongda 364＞sanbei 9.They have all the same variation trend of CHL content.The super high yield corns' CHL content is higher than commons'.The common corns' CHL content declines more quickly in the end than super high yield corns'.The CHL content of xianyu 335 is higher than zhengdan 958.The sequence of four cultivars' CHL content is xianyu 335＞zhengdan 958＞nongda 364＞sanbei 9.The soluble protein content of super high yield corns is higher than common corns' obviously all the time.The max soluble protein content of zhengdan 958 is 48mg/g while two commons' are only 43.2 and 44.8mg/g.The two trends of soluble sugar variation in the leaf are the same.The super high yield corns' soluble sugar content is lower than commons' in prophase but higher in anaphase.The super high yields' POD activity is higher than commons'. The max POD activity of them are 210u/(g·min),195u/(g·min),185u/(g·min) and 177u/(g·min).The sequence is xianyu 335＞zhengdan 958＞nongda 364＞sanbei 9.The super high yields' SOD activity is higher than commons'.The max SOD activity of them are 540 u/(g·min),480 u/(g·min),473 u/(g·min),458 u/(g·min).The sequence is xianyu 335＞zhengdan 958＞nongda 364＞sanbei 9.The super high yields' CAT activity is higher than commons' obviously.The CAT activities of xianyn 335 and zhengdan 958 were rising reciprocally in prophase and closely in anaphase.The max activities are 62.9 u/(g·min),60 u/(g·min),57.1 u/(g·min) and 54.1 u/(g·min).Before filling stage the sequence is xianyu 335＞zhengdan 958＞nongda 364＞sanbei 9.There is not obvious difference on MDA content between two types of corns in prophase.But in anaphase,the MDA content of commons' is higher than the others' significantly.The PEP activity and RuBP activity of supers' are all higher than commons'.Accompanied by the photosynthesis ability descending, the two activities are declining finally.Two types of corns' RuBP activities reach the top and the difference is obvious between two types of corns before filling stage.There is obvious difference between the two types of corns' yield.The yield of Xianyu 335 is the highest,and 3.6%higher than Zhengdan 958,43.3%than Nongda 364,54.4%than Sanbei 9.The sequence is Xianyu 335＞Zhengdan 958＞Nongda 364＞Sanbei 9.