Communities of arbuscular mycorrhizal fungi in maize (Zea mays L.) crops along an edaphoclimatic gradient in Northeast Brazil

Abstract

The objective of this study was to determine the species richness, diversity, and communities of arbuscular mycorrhizal fungi (AMF), based on the morphology of their spores, in maize plantations along an edaphoclimatic gradient going from a humid zone (original area of Atlantic rainforest), to a transition zone and a drier zone (original area of Caatinga), to increase the understanding of the ecology of AMF in tropical agroecosystems. We extracted glomerospores from soil samples from maize plantations in each mesoregion and analysed AMF propagules and community structure. A total of 57 AMF taxa were identified, of which two are new to science. The most probable number of AMF infective propagules did not differ among the three areas. A greater number of glomerospores was obtained from the transition site, whereas species richness for AMF differed between the high humidity and transition sites. The composition of AMF communities differed among sites, with edaphic attributes significantly associated with AMF community composition. The environmental conditions of each mesoregion contribute to the structural differences of AMF assemblages in soils cultivated by the same host plant (maize).

Hierarchical spatial sampling reveals factors influencing arbuscular mycorrhizal fungus diversity in Côte d’Ivoire cocoa plantations

“…A work carried out in Cameroon, comparing natural and anthropic ecosystems, reported AMF spore diversity values (Shannon index) as low as 0.39 for agricultural sites, with forests being richer (0.49) (Snoeck et al 2010 ). These figures are especially low considering reports of AMF spore diversity (Shannon) of 1.4 and 2.27 in alfalfa and sorghum crops in Sudan (Abdelhalim et al 2014 ), 1.96 in maize in Brazil (de Mello et al 2018 ), 2.65 in cassava (Sarr et al 2019 ), and between 1.65 and 2.75 in this study using amplicon sequencing.…”

“…Recent efforts have been made to bridge this gap. However, most of these studies have focused on extraction of AMF spores from the soil and subsequent morphological identification (Abdelhalim et al 2014;de Mello et al 2018;Sousa et al 2018;Marinho et al 2019;Solís-Rodríguez et al 2020) rather than using DNA sequences for identification. Large degrees of variation in spore morphology have been reported even within an AMF species (Walker and Vestberg 1998).…”

Global arbuscular mycorrhizal fungal diversity and abundance decreases with soil available phosphorus

“…The production of spores is part of the AMF life cycle and is highly dependent on environmental conditions, their physiological status and life strategy (de Mello et al, 2018; Smith & Read, 1997). We found that MAP was the best predictor of AMF spore abundance worldwide.…”

Monitoring of Nematofauna and Arbuscular Mycorrhizal Fungi in a Caatinga Area and in the Adjacent Culture

“…In Caatinga plants, Mimosa tenui ora, the most common AMF species in the rhizosphere was Ambispora apendicula, while in Commiphora leptophloeos, the most common AMF species in the rhizosphere were Acaulospora scrobiculata, Gigaspora margarita and Racocetra fulgida (Teixeira-Rios et al, 2018). In an area of Caatinga in Serra Talhada, Acaulospora excavata and Acaulospora denticulata dominated (Mello et al, 2018). While in native and regenerating Caatinga, in addition to pasture, Acaulospora scrobiculata, Glomus macrocarpum and Glomus tortuosum were the AMF species found in all areas (Santos et al, 2018).…”