Influence On Seed Oil Content By Activities Of Several Key Enzymes In Grease Synthesis And Photosynthesis Of The Brassica Napus

In recent years,high oil content has become a new goal of rapeseed quality breeding,and many studies have been done on breeding,cultivation and genetic engineering of domestic and foreign scholars to improve the oil content of rape seeds.However,there are few studies on the physiological and biochemical aspects of rapeseed high oil content In this paper,we mainly focus on the effects of related enzyme activities and photosynthesis on the oil content of rapeseed,and try to find out the key factors affecting the oil content of rapeseed.This study mainly carried out the following work and achieved the relevant results:1.Using Brassica napus varieties or strains with different oil content as experimental material,the activity of 4 key enzymes in the process of grease accumulation,such as Acetyl Co Acarboxylase(ACCase)?Glucose-6-Phosphate Dehydrogenase(G6PDH)?Phospha-tidic acid phophyhydrolase(PPase)?Diacylglycero-lacyl transferase(DGAT),have been detectedby ELISA methods in seed andpod peel at different developmental stages,and the correlation between enzyme activity and seed oil content has been analyzed.The resultshave indicated that the variation trend of enzyme activities in seeds and pod peel of rapeseed cultivars with different oil contents was basically the same,enzymeactivity increased rapidly from the 17 th day after flowering(DAF)to the 24 th DAF,and reached the peak at the 38 thDAF,then decreased gradually.but the enzymeactivity decreased rapidly in Huayou8 with shorter pod ripening time,such as 40.2 days,earlier than the other three varieties for a week.The correlation analysis has showed that the activities of DGAT,PPase and G6 PDH in seeds were extremely significant positively correlated with the seed oil content,the activities of ACCasewere positively correlated with the seed oil content,While the activity of ACCase,G6 PDH,PPase and DGAT in pod peel was positively correlated with the oil content of rapeseed,but did not reach the significant level,The correlations of enzyme activity to oil content of the four kinds of enzymes were DGAT,PPase,G6 PDH and ACCase.Therefore,the gene expression level and enzyme activity level of DGAT and PPase genes in oil accumulation should be considered during the breeding of high oil content rapeseed varieties.2.The photosynthetic intensity and respiration intensity of the four kinds of materials were determined by photosynthesis analyzer,and the correlation analysis was carried out.The results showed that the oil content of rapeseed was consistent with the net photosynthetic rate of leaves,and the leaf respiration had little effect on oil content.