核桃叶片生理性焦枯与矿质元素关系研究

Correlation Analysis between Physiological Scorch and Mineral Elemental Contents in Walnut Leaves

[目的]以叶片营养诊断为主的方法对核桃叶片的矿质元素等指标进行测定和分析,找出核桃叶片焦枯发生的原因,为核桃生产栽培管理提供理论依据。[方法]按叶片焦枯程度对核桃树进行分级,测定不同焦枯程度、不同时期核桃叶片中N、P、K、Na、Ca、Mg、Fe、Mn、Cu、Zn、B元素含量、叶绿素含量,并进行叶片矿质元素间、矿质元素与焦枯程度之间的相关性分析和多元Logistic回归分析。[结果]不同焦枯程度的叶片光合色素的含量随着焦枯程度及时间的推移大体呈下降的趋势,焦枯现象会从叶缘向叶片中部发展。病情程度与N含量呈显著正相关,相关系数为0.63,与P含量呈极显著正相关,相关系数为0.76,与Mn、B含量呈极显著负相关,相关系数分别为-0.73、-0.91。B含量与病情程度的Logistic回归系数值为-0.872,且呈现出0.05水平的显著性(p<0.05),对焦枯程度有显著的负向影响关系。且喷施不同浓度的B肥后焦枯症状得到了有效缓解。[结论]测定分析了‘绿岭’核桃焦枯叶片11种矿质元素含量的关系,发现缺B是引起‘绿岭’核桃叶片焦枯的最主要原因。

[Objective]In this study,the mineral elements and other indicators of walnut leaves were measured and analyzed by the method of leaf nutrition diagnosis,in order to determine the causes of walnut leaf scorching,and then provide a theoretical basis for walnut production,cultivation and management.[Methods]Walnut trees were graded according to the degree of leaf scorch,the contents of mineral elements(N,P,K,Na,Ca,Mg,Fe,Mn,Cu,Zn,B)and chlorophyll in walnut leaves at different scorch degrees and at different periods were measured.And analyze the correlation among mineral elements,and between mineral elements and scorch degree.[Results]The results showed that the contents of photosynthetic pigment in leaves decreased with the increase of scorching degree.The scorching phenomenon developed from the edge to the middle part of the leaves.The degree of illness was significantly positively correlated with N content(R=0.63),significantly positively correlated with P content(R=0.76),and significantly negatively correlated with Mn and B content,with correlation coefficients of-0.73 and-0.91,respectively.The parameter estimated of the content of B in the Logistic regression was-0.872(p<0.05),indicating that B content had a significant negative impact on the degree of scorch.And after spraying different concentrations of B fertilizer,the symptoms of scorching and withering were effectively alleviated.[Conclusion]Lack of B is the main reason for the scorching of‘Lyuling’walnut leaves.