丛枝菌根真菌对旱稻生长、Cd吸收累积和土壤酶活性的影响

Effects of Arbuscular Mycorrhizal Fungi(AMF) on Growth and Cd accumulation of Upland Rice and Soil Enzyme Activities in Cadmium Contaminated Soil

通过盆栽实验,研究了土壤不同Cd添加水平(0、2、10 mg·kg-1)下,接种丛枝菌根真菌摩西球囊霉(Glomus mosseae,GM)对旱稻(Oryza Sativa L.)生长、Cd吸收累积和根际土壤酶(脲酶和蔗糖酶)活性的影响。结果表明,GM菌可有效侵染旱稻根系,其侵染率为37%~72%,随Cd污染程度增加而显著降低。接种GM菌使旱稻根际土壤脲酶及蔗糖酶活性显著提高,提高幅度为9.6%~44.5%,从而促进根际土壤碳素和氮素循环,并显著提高旱稻根系、地上部和籽粒的生物量,提高幅度为10.4%~57.1%;接种GM菌同时可降低旱稻对Cd的富集和转运能力,从而显著降低其各部分尤其是籽粒中的Cd含量,降幅为26.8%~57.1%。

Arbuscular mycorrhizal fungi(AMF)have showed to enhance plant resistance to environmental stresses. In this study, the effects of AMF(Glomus mosseae, GM)on growth and Cd accumulation and rhizospheric soil enzyme(urease and invertase)activities of upland rice were investigated under different Cd addition levels(0, 2, 10 mg·kg-1) in a pot trail. The colonization rates of upland rice roots by GM ranged from 37% to 72% and decreased with increasing soil Cd concentrations. The mycorrhizal colonization significantly enhanced soil en-zyme(urease and sucrase)activities(ranging from 9.6%~44.5%), promoted carbon and nitrogen metabolisms in the rhizosphere, and in-creased upland rice biomass(ranging from 10.4%~57.1%), as compared with the non-mycorrhizal upland rice. The uptake and transfer of Cd in upland rice and Cd concentrations in rice grains(ranging from 26.8%~57.1%)were significantly decreased by GM inoculation.