苹果树叶面肥的优化及其对果树生长和抗氧化性的影响

Optimization of Apple Leaf Surface Fertilizer and Its Effect on the Growth and Antioxidant Capacity of Fruit Trees

本研究旨在开发一种新型苹果树叶面肥配方,从而为苹果树的栽培提供参考。本研究在2017-2018年间开花之后对160棵‘长富2号’富士苹果树进行叶面施肥,肥料配方为:尿素(N) 0.64%、过磷酸钙(P)0.61%、硝酸钙(Ca) 1.86%、硼酸(B) 0.19%、硫酸锌(Zn) 0.38%、硫酸锰(Mn) 0.25%和硫酸铁(Fe) 0.01%。果实成熟期收集叶片和果实,分别检测叶片和果实中的营养元素含量,并测量苹果树的总花序数量、花序坐果率、春梢和秋梢长度及单株产量。检测两种处理的叶片中超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性及丙二醛(MDA)含量。检测两种处理的果实中总可溶性固形物含量和可溶性糖含量。结果显示,与对照组比较,施肥组的花序坐果率、单株产量、单株苹果个数均显著升高(P<0.05)。两组苹果树叶片中的N、P和Ca水平未见显著差异(P>0.05),但施肥组苹果树的叶片和果实中的B、Zn、Mn和Fe的含量明显升高(P<0.05)。叶面喷施营养元素提高了叶片中SOD、POD和CAT的活性,并降低了MDA的含量(P<0.05)。叶面喷施营养元素提高了果实中总可溶性固形物含量和可溶性糖含量(P<0.05)。本研究表明,叶面营养元素施肥可明显提高苹果树的营养状况,其营养机制可能与B、Zn、Mn和Fe 4种微量元素的补充有关,本研究可为苹果树的叶面施肥方式提供参考依据。

The purpose of this research is to develop a new fertilizer formula for apple leaves,so as to provide a reference for the cultivation of apple trees.In this study,160 ’Changfu No.2’ Fuji apple trees were fertilized after flowering from 2017 to 2018.The fertilizer formula was as follows:Urea(N) 64%,Superphosphate(P) 0.61%,Calcium nitrate(CA) 1.86%,Boric acid(B) 0.19%,Zinc sulfate(Zn) 0.38%,Manganese sulfate(Mn) 0.25% and Iron sulfate(Fe) 0.01%.The leaves and fruits were collected during the fruit maturity period,and the nutrient element contents in the leaves and fruits were detected respectively,and the total inflorescence number,inflorescence fruit setting rate,spring and autumn shoot length and yield per plant of apple trees were measured.The activity of superoxide dismutase(SOD),peroxidase(POD),catalase(CAT) and the content of malondialdehyde(MDA) in the leaves of the two treatments were detected.The total soluble solid content and soluble sugar content in the fruits of the two treatments were detected.The results showed that compared with the control group,the inflorescence fruit setting rate,the yield per plant,and the number of apples per plant in the fertilization group were significantly increased(P<0.05).There was no significant difference in the levels of N,P and Ca in the leaves of the two groups of apple trees(P>0.05).Compared with the control group,the contents of B,Zn,Mn and Fe in the leaves and fruits of apple trees in the fertilization group were significantly increased(P<0.05).Foliar spraying of nutrient elements increased the activities of SOD,POD and CAT in leaves,and reduced the content of MDA(P<0.05).Foliar spraying of nutrient elements increased the total soluble solid content and soluble sugar content in the fruit(P<0.05).This study shows that the fertilization of foliar nutrients can significantly improve the nutritional status of apple trees,and the nutritional mechanism may be related to the supplementation of four trace elements B,Zn,Mn and Fe,this study can provide a reference for the foliar fertilization methods of apple trees.