叶面喷施氮素对葡萄成熟后期叶片生理生化指标及果实品质的影响

摘要

在葡萄果实成熟后期,为延缓叶片衰老,提高功能叶的光合功能,采取田间试验,研究了喷施不同浓度的氮素对设施栽培中葡萄叶片衰老生理以及果实品质的影响.结果表明:在适度浓度下,叶面喷施尿素,(1)增加了葡萄叶片的叶绿素、可溶性蛋白含量,提高叶片的净光合速率,有助于叶片养分的积累;(2)增强了叶片中的SOD、POD等抗氧化酶活性,降低了叶片MDA含量,提高了叶片的抗衰老性;(3)提高了葡萄果实的可溶性固形物、Vc、总糖以及糖酸比,降低了果实的有机酸含量,一定程度上提高了果实品质.其中喷施0.4％和0.8％的尿素能使葡萄叶片衰老延缓15 d左右,但较高浓度的尿素对花青素的合成可能产生一定的阻碍.%The effects of spraying different concentrations of nitrogen on leaf senescence physiology and fruit quality of grape were studied.The results showed that with the experimental concentration,foliage spraying nitrogen can increase contents of chlorophyll and soluble protein in grape leaf and leaf Pn,so it is contributive to accumulate nutrients of leaf; it also can enhance the activities of antioxidative enzymes (SOD and POD) in leaf,decrease the leaf MDA content,thereby improving anti-aging capability of leaf; in additional,it increased the contents of soluble solids,Vc and total sugar and the ratio of sugar to acid of grape fruit,and decreased the content of organic acid in fruit,thus improving the fruit quality.Treatment with foliage spraying of 0.4％ or 0.8％ urea could make senescence of grape leaves delaying about 15 d.However,the high concentration of nitrogen may block the synthesis of anthocyanin.