A comparison of the arbuscular mycorrhizal fungal communities among Bangladeshi modern high yielding and traditional rice varieties

Abstract

AimsArbuscular Mycorrhizal Fungi (AMF) are ubiquitous soil microorganisms playing a vital role in the functioning of agricultural ecosystems. Although AMF are generally considered to have a low host specificity, it has been suggested that modern plant breeding has selected crop genotypes that are more selectively associated with AMF, possibly resulting in modern high yielding varieties (HYV) having a lower AMF diversity than traditional crop varieties.Whether this is true for paddy rice varieties under field conditions is not known so far. Here, we aimed at comparing differences of AMF communities among modern HYV and traditional rice varieties. MethodsWe collected root and soil samples of five Bangladeshi rice varieties (two traditional and three modern HYV) from 40 different rice fields and quantified AMF richness, diversity and community composition through high throughput amplicon sequencing of the small subunit (SSU) of the ribosomal RNA cistron. ResultsOverall, 75 AMF OTUs, distributed over six AMF families with Glomeraceae as predominant family were found.After accounting for differences in soil conditions, we found that AMF diversity significantly differed among the five varieties and was higher in the traditional than modern varieties. The composition and structure of the AMF communities were distinct between the traditional and modern varieties. An indicator species analysis detected 9OTUs significantly associated with traditional rice varieties, whereas no indicator OTUs were found for the modern HYV. ConclusionsWe conclude that modern breeding coupled with high fertilizer application rates provide a plausible explanation for the reduced AMF diversity and the different AMF community composition between Bangladeshi modern HYV and traditional varieties.

A review on the impact of domestication of the rhizosphere of grain crops and a perspective on the potential role of the rhizosphere microbial community for sustainable rice crop production

“…In particular, increasing evidence has been provided suggesting that the domestication of legume crops has affected their compatibility with rhizobial strains and AMF due to the reduced genetic diversity of host plants, resulting in a reduction of AMF diversity and colonization of legume roots (Liu et al, 2020). Analysis of AMF responsiveness in 27 crop species indicated stronger AMF colonization in wild progenitor crops, while domesticated crops only benefited from AMF under low phosphorus availability conditions (Parvin et al, 2021). Recent studies have also suggested that changes in the plant-AMF relationship have occurred in response to the domestication of rice.…”

Variation in mycorrhizal growth response among a spring wheat mapping population shows potential to breed for symbiotic benefit

“…It is important to note that our inoculum comprised a mix of 5 species of AM fungi—without molecular identification we cannot comment on the diversity or evenness of the intraradical community here. The extent to which cereal crop genotype influences intraradical AM fungal community composition is unclear (Aguilera et al, 2014 ; Parvin et al, 2021 ; Stefani et al, 2020 ). Conceivably, lines showing negative response to AM fungal inoculation could have intraradical fungal communities dominated by different fungal genotypes than those found in positive responding lines.…”