作物间作对油菜积累镉与铅的影响

Effects of Intercropping on Accumulation of Cd and Pb in Oilseed Rape

采用盆栽试验,研究了与黑麦草(Lolium perenne)及紫云英(Astragalus siniucus)间作对芥菜型油菜(Bras-sica juncea)和甘蓝型油菜(B.napus)积累镉与铅的影响。结果表明:单种和混种紫云英显著增加土壤氮,单种和混种油菜及黑麦草显著降低土壤氮。栽培植物增加土壤的碱解氮、速效磷、速效钾和有机质,单种紫云英显著降低土壤pH值。间作时,两种油菜的生物量显著增加,其SOD活性显著降低,黑麦草和紫云英的SOD活性显著增加,两种油菜的镉和铅含量显著降低,黑麦草和紫云英的根部的镉和铅含量显著增加,两种油菜地上部和根部的镉与铅的生物富集系数显著下降,黑麦草和紫云英的根部的镉和铅的生物富集系数显著增加。因此,与黑麦草及紫云英间作可减少油菜积累镉与铅,降低重金属对人类危害。

A pot experiment was conducted to investigate the effect of 2 intercrops on Cd and Pb uptake by two oilseed rape species,Brassica juncea and B.napus.The intercrops included ryegrass（Lolium perenne） and Chinese milkvetch（Astragalus siniucus）.Monocropped and intercropped chinese milkvetch significantly increased soil total nitrogen.Monocropped and intercropped oilseed rapes and ryegrass significantly decreased soil total nitrogen.Soil available N,P,K,and organic matter increased with monocropping and intercropping these plants.Soil pH significantly decreased with planting Chinese milkvetch alone.Intercropping significantly increased biomass for both oilseed rapes.SOD activity of seedling,contents of Cd and Pb in tissues and bioconcentration factor of both metals were greatly decreased for both oilseed rapes intercropped with ryegrass and Chinese milkvetch.Intercropping greatly increased SOD activity of seedling,Cd and Pb contents in root,and bioconcentration factor of metals in root for ryegrass and Chinese milkvetch.The results suggested that intercropping might be a feasible tool in decreasing accumulation of Cd and Pb by oilseed rape and reducing the risk of metals to human beings.