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锌在玉米栽塔中普遍缺锌。在植株不同生长阶段症状差异很大。最初表现为基部第三张次生叶的叶脉二边退色,并很快蔓延形成二条半透明的灰白带,伸展到叶的顶端。严重时,新叶继续退色,老叶则呈铜红色,以后变成紫色,最后坏死。造成缺锌的原因是:连续耕作,全锌含量减少或耗尽;酸性上施泥灰石或石灰过量;磷养分过多;多次连作;出苗后几周遇低温,湿度过大;栽培方式不良,引起土壤结构恶化。防治方法:Hoorer(1964)主张根据缺锌的程度和土壤情况,在播种以后每公顷施2到20公斤金
Zinc corn planting tower generally zinc deficiency. In different stages of the plant symptoms vary greatly. Initially manifested as the base of the second leaf of the secondary veins fade on both sides, and soon spread to form two translucent gray band, stretching to the top of the leaf. Serious, the new leaves continue to fade, the old leaves were copper red, purple later, finally necrosis. Zinc deficiency caused by the reasons are: continuous farming, reduced or depleted total zinc; acid on the implementation of excessive limestone or lime; too much phosphorus nutrients; multiple continuous cropping; weeks after emergence of low temperature, humidity is too large; cultivation methods Bad, causing the deterioration of soil structure. Control methods: Hoorer (1964) advocated that according to the degree of zinc deficiency and soil conditions, after sowing hectare applied 2 to 20 kg of gold