Arbuscular mycorrhizal colonization of a Cd hyperaccumulator Viola baoshanensis at Baoshan Pb/Zn Mine

Abstract

Abstract Despite great potential for arbuscular mycorrhizal (AM) fungi associated with heavy metals (HMs) hyperaccumulators in the phytoremediation of contaminated sites, rather limited information is available in literature about the community structure of AM fungi (AMF) in the rhizosphere of hyperaccumulators in nature. A field survey was conducted to investigate the colonization status and community structure of AMF of Viola baoshanensis, a Cd hyperaccumulator, growing at Baoshan Pb/Zn Mine. Shoot/root ratios of 1.78 for Cd, and 2.57 for Zn in V. baoshanensis indicate that these two metals were preferentially transported from roots to shoots, whereas Pb was mainly stored in roots. The roots of V. basshanensis were extensively colonized by AMF with M% of 69.1%, and A% of 46.9%, whereas mycorrhizal colonization was not affected by concentrations of Cd, Zn and Pb in the soil. 15 AMF species ( 5 Glomus, 3Rhizophagus,2 Claroideoglomus, 2 Septoglomus, and each one of Ambispora, Funneliformis, and Sclerocystis ) were identified by a morphological method. The dominant AMF genus was Glomus, showing high tolerance to excess Cd, Zn and Pb, while Glomus ambisporum and Claroideoglomus etunicatum were the most abundant species in the rhizosphere of V. baoshanensis.