施用富集植物秸秆对水田芥生长及镉积累的影响

Effects of Applying Accumulator Plant Straw on Growth and Cadmium Accumulation of Nasturtium officinale

【目的】研究陆生富集植物秸秆对水生富集植物的镉积累影响。【方法】采用盆栽试验,通过向土壤中施用4种陆生镉富集植物(白三叶、旱莲草、小飞蓬和繁缕)秸秆,研究在镉胁迫条件下,施用富集植物秸秆对挺水镉富集植物水田芥生长以及镉积累的影响。【结果】施用4种镉富集植物均提高了水田芥茎秆、叶片和地上部分生物量。与未施用相比,施用富集植物秸秆均提高了水田芥叶片的抗氧化酶活性,增加水田芥叶片的可溶性蛋白含量。施用白三叶、旱莲草、小飞蓬秸秆均降低了水田芥茎秆、叶片与地上部分的镉含量,只有施用繁缕秸秆增加了水田芥茎秆、叶片和地上部分镉含量,较未施用分别增加了40.57%、13.76%和25.44%。施用旱莲草秸秆与施用繁缕秸秆的水田芥茎秆、叶片和地上部分镉积累量增加,其中施用繁缕秸秆比未施用分别增加了53.70%、21.19%和35.62%。施用繁缕秸秆提高了土壤酶(过氧化氢酶、脲酶和蔗糖酶)活性,而其他3种处理则降低了土壤酶活性。【结论】施用繁缕秸秆能够增加水田芥对镉的积累,提高水田芥对镉污染土壤的修复能力。

【Objective】To study the effects of terrestrial accumulator plant straw on cadmium accumulation of aquatic accumulator plant.【Method】The pot experiment was conducted to research the effects of applying four terrestrial accumulator plant species(Trifolium pretense,Eclipta prostrate,Conyza canadensis and Stellaria media) straw in soil on growth and cadmium accumulation of Nasturtium officinale under cadmium stress.【Results】Applying four accumulator plant species straw increased stem,leaf and shoot biomasses of N. officinale. Compared with the control,applying four accumulator plant species straw enhanced the antioxidant enzyme activity,and increased the soluble protein content of N. officinale. When applying the straw of T. pretense,E. prostrate and C. canadensis in soil,the cadmium contents decreased in stems,leaves and shoots of N. officinale,but the straw of S. media increased of that compared with control. The straw of E. prostrate and S. media increased cadmium accumulation amounts in stems,leaves and shoots of N. officinale,and S. media straw increased that by 53.70%,21.19% and35.62% compared with the control,respectively. However,only S. media straw enhanced soil enzyme(catalase,urease and sucrase) activity compared with the control,while other three accumulator species reduced it.【Conclusion】Applying S. media straw could increase cadmium accumulation of N. officinale,and improve the phytoremediation ability of N. officinale for cadmium contaminated soil.