Zn肥基施对水稻吸收转运Cd的影响

Effect of Zinc Fertilization on Cadmium Absorption and Transport in Rice

为探明湖南典型镉(Cd)污染稻田施锌(Zn)对水稻Cd吸收积累的效果,采用Zn肥基施的方法研究施Cd-Zn交互作用对水稻Cd吸收转运的影响,指导Cd污染稻田Zn肥的施用。结果表明,施Zn可显著提高土壤有效态Zn含量,增加水稻对Zn的吸收积累,并显著抑制水稻对Cd的吸收,但对土壤有效态Cd含量无显著影响。早稻基施Zn肥15~60 kg/hm^2的米Cd含量降低17.52%~37.13%、晚稻米Cd含量降低11.21%~66.00%,早稻米Cd含量随Zn肥施用量的增加呈"报酬递减"规律,而晚稻米Cd含量则随Zn肥施用量的增加呈直线下降趋势;其中,早稻较佳Zn肥施用量为45 kg/hm^2。试验结果还表明,水稻米、茎、叶间Zn-Cd交互作用显著,施Zn可显著抑制水稻对土壤Cd的吸收转运,且米Cd含量既受水稻吸收转运Cd能力的影响,还受水稻植株和土壤中Cd-Zn拮抗作用的调控。

To explore the effect of zinc fertilization on cadmium absorption and transport in rice,using zinc fertilization application in typical Cd-Contaminated paddy soil to investigate the influence of Cd-Zn interaction on Cd uptake and translocation in rice,so to guide the using of Zn fertilizer on Cd-Contaminated paddy soil.Data showed application of the Zn fertilizer resulted in soil available Cd contents reduced,Zn fertilizers accumulation increased and an obviously inhibition of Cd absorption in rice,however,there was no significant effect on the available Cd content decrease in soil.The Zn fertilizer applied at 15-60 kg/ha reduced the Cd concentration in early rice grain about 17.52%-37.13%and late rice about 11.21%-66.00%.Cd content in early rice decreased with the Zn fertilizer application accumulation,which coincided with the law of diminishing return.While Cd content in late rice declined linearly with increased of Zn fertilizer application.Results demonstrated optimal Zn fertilizer application amount was 45 kg/ha.In addition,interaction of Zn-Cd in rice,stems and leaves were remarkable.Zn application significantly inhibit the absorption and translocation of Cd from soil.Rice Cd contents was both affected by rice absorption and translocation ability and controlled by the antagonistic action of Cd-Zn in rice plants and soil.