Leaf senescence and reactive oxygen metabolism of buckwheat under continuous cropping
[Objective] This study aimed to research functional leaf senescence and reactive oxygen metabolism of buckwheat at different years in continuous cropping system,and investigate the mechanism of leaf senescence and the internal physiological mechanism of yield formation.[Method] Taking ‘Xinong 9920’ tartary buckwheat as material and rotation cropping system as control (CK),a series of experiments were conducted on the basis of 4 years to research the change in contents of chlorophyll and soluble protein,activities of SOD and POD,and accumulation of MDA and OFR of buckwheat's functional leaf.The yield,1 000 grain mass,height and number of main stem sections were also measured when harvesting and their relationship with leaf physiological indexes was analyzed.[Result] With the continuation of aging process,SOD activity and contents of chlorophyll and soluble protein decreased,while POD activity and MDA and OFR accumulation increased continuously after anthesis.With the increase of continuous cropping years,contents of chlorophyll and soluble protein decreased,MDA and OFR accumulation increased,and these values of continuous cropping were higher than that of rotation cropping.SOD activity firstly increased followed by decrease.POD activity decreased significantly before anthesis and increased significantly in the late growth stage (21 d after anthesis).The grain yield had a very significant positive correlation with soluble protein content,a significant positive correlation with chlorophyll content,and a very significant or significant negative correlation with POD activity as well as MDA and OFR accumulation.[Conclusion] With the increase of continuous cropping years,the functional period of leaf shortened,the degree of reactive oxygen damage aggravated,and the grain yield decreased.
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万方数据
维普
