马铃薯对锌元素的奢侈吸收

通过亩施锌肥(ZnSO_4·7H_2O)0,5,50,500和1000公斤来研究马铃著对不同剂量锌,特别是高剂量锌的反应,为生长在可能有重金属污染田块上的块茎类作物进行一些环保和食品卫生方面的分析.试验结果表明,较高剂量的锌(5～500公斤/亩)延缓了马铃薯茎叶的生产,对块茎的产量反而有促进作用.亩施锌1000公斤的处理对茎叶和块茎产量都有显著的抑制作用,但尚未达到大幅度减产或致死的程度.马铃薯体内含锌量的分布为:茎>块茎>叶.块茎富锌幅度为25.5～102.9mg/kg(干重).茎部含锌量在始花期高,收获期低;叶片含锌量在两个时期变化不大,说明茎内锌比叶片内锌更易向块茎转移.

LUXURY ABSORPTION OF ZINC BY POTATO PLANT

The experiment was conducted to study the growth response of potato planted to soils treated with 0,5,50,50,500,1000kg ZnSO_4·7H_2O per mu, and especially those of excessive Zinc (Zn) inputs. The possible hazard which may affect soil environment and people's diet were the main concerns of the rescarch. Rcsult of the experiment indicated that the heavier application of Zn fertilizer (5～500kg/mu) retarded potato stalk and leaves growth while promoted tuber development. The Zn rate of 1000 kg/mu which caused obvious growth reduction to stalk, leaves and tubers showed no drastic decline in potato production and was far from the lethal dosage. The magnitude of Zn contents in potato tissues werc in the order of stalk>tuber>leaves. The tuber Zn concentration ranges from 26～103 mg/kg on the dry matter basis. The leaf Zn was quite stable between periods of florescence and maturity while that in stalk was much higher during florescence than maturity, implying possible Zn transfer from potato stalks to tuber in the course of tuberization.