土施富集植物秸秆对牛膝菊生长及镉积累的影响

摘要

To study the allelopathy effects of accumulator straw on hyperaccumulator,a pot experiment was con-ducted to study the effects of applying accumulators (Conyza canadensis,Cardamine hirsuta,Eclipta prostrata and Nasturtium officinale)straws in soil on growth and cadmium accumulation of Galinsoga parviflora under cadmium pollution.The results were as follows:Compared with non-application (control),the application of C.canadensis and C.hirsute straws improved the roots,stems,leaves,shoots and whole plants biomasses of G.parviflora,and the plant height and antioxidant enzymes (SOD,POD and CAT)activity of G.parviflora also increased.The straws of E.pros-trate and N.officinale reduced the biomass,plant height and antioxidant enzyme activity of G.parviflora.The straws of C.canadensis,C.hirsuta,E.prostrata and N.officinale improved cadmium content in shoots of G.parviflora,which improved 1 2.01 %,9.55%,22.03% and 5.39% respectively compared with control,but only C.canadensis and C.hirsuta straws improved the cadmium accumulation in shoots of G.parviflora (which improved by 35.78% and 1 1 .77% respectively compared with control).C.canadensis and C.hirsuta straws increased soil catalase activity, soil urease activity and soil invertase activity,and the straws of E.prostrata and N.officinale reduced soil activity. Therefore,the applying C.canadensis and C.hirsuta straws in soil could improve cadmium contaminated soil remedy ability of G.parviflora,and C.canadensis straw was the best one.%为研究富集植物秸秆对超富集植物的化感作用，通过盆栽试验，研究了镉污染条件下，土施4种镉富集植物（小飞蓬、碎米荠、旱莲草和豆瓣菜）秸秆对牛膝菊生长及镉积累的影响。结果表明：与未施用相比，施用小飞蓬和碎米荠秸秆提高了牛膝菊根系、茎秆、叶片、地上部分及整株生物量，也提高了牛膝菊株高和抗氧化酶（SOD、POD 和CAT）活性，但施用旱莲草和豆瓣菜秸秆则降低了牛膝菊的生物量、株高和抗氧化酶活性。施用小飞蓬、碎米荠、旱莲草和豆瓣菜秸秆均提高了牛膝菊地上部分镉含量，分别比未施用提高了12．01％，9．55％，22．03％，5．39％，但只有施用小飞蓬和碎米荠秸秆的牛膝菊地上部分镉积累量高于未施用（分别比未施用提高了35．78％和11．77％）。施用小飞蓬和碎米荠秸秆提高了土壤过氧化氢酶活性、土壤脲酶活性和土壤蔗糖酶活性，而施用旱莲草和豆瓣菜秸秆则降低了土壤酶活性。因此，土施小飞蓬和碎米荠秸秆均能提高牛膝菊对镉污染土壤的修复能力，以小飞蓬秸秆的效果最佳。