果树正常生长发育不仅需要大量元素,而且还需要较少的锌、硼、镁等微量元素。土壤中缺乏镁、硼、锌等微量元素,影响果树生长发育和开花结实。一、缺锌症锌是果树所必需的营养元素。缺锌的果树吲哚乙酸减少,果树生长受到抑制,表现出小叶病或簇叶病等。锌能促进愈伤 Normal growth and development of fruit trees not only need a large number of elements, but also less zinc, boron, magnesium and other trace elements. The lack of soil magnesium, boron, zinc and other trace elements, affecting the growth and development of fruit trees and flowering and fruiting. First, zinc deficiency Zinc is a fruit tree essential nutrients. Zinc deficiency in the fruit of indole acetic acid decreased, inhibited the growth of fruit trees, showing leaflet disease or leaf-leaf disease. Zinc can promote callus