Six-year fertilization modifies the biodiversity of arbuscular mycorrhizal fungi in a temperate steppe in Inner Mongolia

Abstract

a b s t r a c tArbuscular mycorrhizal fungi (AMF) play key roles in supporting ecosystem sustainability, stability and function, but little is known about how fertilization practices affect AMF abundance and community composition in the grassland ecosystems. In the present study, a field trial was established to examine the effects of 6 years of nitrogen (N) and phosphorus (P) fertilization on the community structure of AMF both in soils and plant roots in a typical temperate steppe in Inner Mongolia, northern China. The AMF small-subunit (SSU) rRNA genes were subjected to PCR, cloning, sequencing, and phylogenetic analyses. A total of 1554 sequenced SSU rRNA clones, including 919 clones from the soil and 635 clones from the roots, were analyzed. The 31 AMF sequence types belonging to Glomeromycota were identified: 17 to Glomus group A and 14 to Glomus group B. The experimental results indicated that N fertilization significantly altered the AMF communities in both soils and mixed roots but had no obvious influence on AMF abundance. However, P fertilization showed no significant influence on the AMF community structure, but induced a significant decrease in mycorrhizal colonization rate, arbuscule colonization and hyphal length density. Furthermore, N and P application showed significant interactions in affecting AMF species compositions in soils but not in roots. Generally the AMF diversity in the soil was higher than that in the roots. The study suggested that N fertilization predominantly altered AMF species composition, while P fertilization influenced AMF abundance in this steppe.

Arbuscular Mycorrhizal Diversity and Function in Grassland Ecosystems

“…Microbial diversity was assessed by preparing clone libraries and analysing with Sanger sequencing methods (Chen et al 2014;Liu et al 2012;Santos-González et al 2007;Yang et al 2010). Data generated from these molecular techniques has revealed that the community structure and diversity of AM fungi in grassland are strongly influenced by seasonality, fertilisation and management practices (Chen et al 2014;Montero Sommerfeld et al 2013;Yang et al 2010).…”

“…Microbial diversity was assessed by preparing clone libraries and analysing with Sanger sequencing methods (Chen et al 2014;Liu et al 2012;Santos-González et al 2007;Yang et al 2010). Data generated from these molecular techniques has revealed that the community structure and diversity of AM fungi in grassland are strongly influenced by seasonality, fertilisation and management practices (Chen et al 2014;Montero Sommerfeld et al 2013;Yang et al 2010). With the advent of the next-generation sequencing (NGS), AM fungal diversity, function and distribution patterns are now being examined at levels that were unthinkable only a decade ago (Ö pik et al 2010;Schüßler and Walker 2010;Stürmer 2012) which has significantly improved our understanding of their role in grasslands and other environments (Dumbrell et al 2011;Krüger et al 2012;Redecker et al 2013;Stockinger et al 2010).…”

“…In general, increasing levels of fertilisation, whether they are synthetic or manures, is usually associated with reduced diversity of AM fungi compared to unfertilised grassland soils (Chen et al 2014;Christie and Kilpatric 1992;Murugan et al 2013;Wuen et al 2002). However, the AM fungal community response to fertilisation is largely dependent upon the loading amount, fertiliser type and combination and the method of application (Chen et al 2014;Lin et al 2012).…”

“…However, the AM fungal community response to fertilisation is largely dependent upon the loading amount, fertiliser type and combination and the method of application (Chen et al 2014;Lin et al 2012). For example, AM fungal colonisation in two wild plant species was higher in the unfertilised compared to the grassland receiving phosphate fertilisation (Wuen et al 2002).…”

Fungos micorrízicos arbusculares e endofíticos dark septate em áreas de Mata Atlântica em um gradiente altitudinal

“…Pesquisas recentes mostraram que a planta hospedeira seleciona e determina os parceiros da simbiose através de sinalizadores moleculares presentes nos exsudatos radiciais e que esta pode detectar, discriminar e premiar os melhores parceiros fúngicos com mais carboidratos (KIERS et al, 2011). Semelhante ao estudo em pauta, um domínio na comunidade de FMA por Glomeraceae também foi relatado em outras áreas florestais (HUSBAND et al, 2002;ÖPIK et al, 2008), em pastagens e em áreas agrícolas (HIRIJI et al, 2006;CHEN et al, 2014 Lavras, v. 8, p. 77-87, 2002.…”