近年来 ,宁夏果树黄化病发生严重 ,主要危害苹果、桃、杏、李子等 ,轻则影响生长发育和产量 ,重则不结果 ,甚至整株枯死 ,这是一种世界性难以防治的果树生理病害。果树黄化的诱因很多 ,如施肥、修剪不当、灌水、挂果太多、地下水位过高 ,磷肥及氮素化肥施用太多及缺铁均可引起 In recent years, Ningxia fruit tree yellowing disease serious, the main harm to apples, peaches, apricots, plums, ranging from the impact of growth and yield, weight is not the result, even the entire dead, which is a worldwide fruit tree is difficult to control Physiological diseases. Many causes of yellowing of fruit trees, such as fertilization, improper pruning, irrigation, fruiting too much groundwater level is too high, phosphorus fertilizer and nitrogen fertilizer too much and iron deficiency can cause