一、目的:锌是植物正常生长不可缺少的微量营养元素。近年来,在新修梯田中种植的玉米出现了“白苗”症状。即玉米出苗一、二周,“白色幼苗”开始呈现,新生的嫩叶片为淡黄色,甚至为白色,基部叶片尤为显著;生长后期,在叶脉间呈现淡黄色和淡绿色相间的斑块或条纹;节间变短,长势衰弱,严重影响玉米的生长和产量。群众称作“白苗病”或 First, the purpose: zinc is an essential micronutrient for normal plant growth. In recent years, the corn planted in the newly-built terraces has the symptoms of “white seedlings.” That is, one or two weeks after the emergence of corn, “white seedlings” began to appear. The newborn leaves were yellowish, even white, especially in the basal leaves. Late in the growth period, patches or streaks of light yellow and light green appeared between the veins, ; Internodes shorter, weakening, seriously affecting the growth and yield of corn. The masses called “white seedling disease” or