叶面肥抑制春小麦Cd吸收效应研究

Effect of different foliar fertilizers on alleviating cadmium toxicity in spring wheat

为降低小麦籽粒对镉(Cd)的积累能力,确保食品安全,明确田间条件下不同叶面肥抑制小麦Cd吸收的效应,选取中轻度Cd污染小麦田土壤为对象,采用大田试验,研究了在分蘖期和孕穗期喷施不同种类叶面肥(磷肥(P)、锰锌肥(Mn+Zn)、多元素复合肥(M)、有机水溶性肥(O))对小麦不同器官中Cd的含量、分配以及Cd富集的影响。结果显示:喷施叶面肥后小麦籽粒中Cd含量均可下降到食品污染物标准规定值(≤0.1mg/kg)范围内,以喷施锰锌肥籽粒降Cd效果最佳,降Cd率可达41.72%;锰锌肥、多元素复合肥的施用显著降低了小麦地上部的Cd含量(p<0.05),小麦地下部的Cd含量只有喷施锰锌肥处理显著高于不喷施叶面肥处理(p<0.05);喷施磷肥和锰锌肥使小麦籽粒中Cd的分配比例显著下降了2.12%和2.47%;喷施叶面肥首先抑制了叶对Cd的富集,其次是显著降低了籽粒Cd的富集。综合考虑认为,小麦在分蘖期和孕穗期叶面喷施锰锌微肥籽粒降Cd作用最显著,在生产实践中适宜在中轻度Cd污染农田土壤利用中优先推荐。

In order to reduce the accumulation of cadmium(Cd)in wheat grains and ensure food safety,the effects of different leaf fertilizers on inhibiting Cd absorption in wheat under field conditions were studied.The soils of wheat field with moderate and mild Cd pollution were selected as the object.By field experiment,different kinds of foliar fertilizers(phosphorus fertilizer(P),manganese zinc fertilizer(Mn+Zn),multi-element compound fertilizer(M)and organic water-soluble fertilizer(O),were applied at tillering stage and booting stage,and then the distribution and enrichment of Cd in different organs of wheat were analyzed.Results show that,after spraying foliar fertilizer,the content of Cd in wheat grains is reduced to the standard value of food pollutants(≤0.1mg/kg),and application of manganese zinc fertilizer obtains the best Cd reduction effect in wheat grain,and the Cd reduction rate reaches 41.72%.The application of manganese zinc fertilizer and multi-element compound fertilizer significantly decreases the Cd content in above ground organs of wheat(p<0.05).The Cd content in roots of the wheat treated with manganese zinc fertilizer is significantly higher than that of control(p<0.05).The distribution ratio of Cd in wheat grain decrease by 2.12%and 2.47%after applying phosphorus fertilizer and manganese zinc fertilizer.Foliar fertilizers inhibit the enrichment of Cd in leaves,and then significantly reduce the enrichment of Cd in grains.It is concluded that manganese zinc fertilizer application on wheat leaves at tillering stage and booting stage has the most significant effect on Cd reduction,and is recommended to the wheat field with moderate and mild Cd pollution in production practice.