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杨树是世界中纬度平原地区栽培面积最大的速生树种之一,具有生长快、成材早、产量高、易于更新和适宜工业化加工等优点,被广泛地用于集约栽培和四旁绿化。随着杨树人工林栽培面积的不断增加和新品系逐年引进,杨树病虫害的发生与危害呈现出日趋加重的局面。最近几年的林木病虫情况调查表明:杨树缺铁性黄化病的发生面积、株数逐年增多,已由当初发生于杨树育苗地,发展到定植后2年～5年生的幼树,由点状零星到大面积连片发生,发生时间也由过去6月提前到现在的4月上中旬。是一种非寄生性的杨树病害,系林地土壤缺铁所致。
Poplar is one of the fast-growing tree species with the largest cultivated area in the mid-latitude plains in the world. It has the advantages of rapid growth, early harvest, high yield, easy regeneration and industrialized processing. It is widely used in intensive cultivation and greening around. With the growing area of poplar plantations and the introduction of new lines year after year, the occurrence and harm of poplar pests and diseases are showing an increasingly serious situation. In recent years, surveys of forest pests and diseases showed that the area and number of poplar trees with iron-deficiency yellow disease increased year by year from the original poplar seedling growing area to the saplings aged from 2 to 5 years after planting, From sporadic sporadic to large area contiguous occurred, the timing of the advance from the previous June to the present mid-April. Is a non-parasitic poplar disease, Department of forest soil iron deficiency caused.