Influence of elevated CO2 on arbuscular mycorrhizal fungal community elucidated using Illumina MiSeq platform in sub-humid tropical paddy soil

Abstract

Arbuscular mycorrhizal fungi (AMF) are one of the beneficial soil microbial communities, playing an important role in abiotic and biotic stress management in agricultural crops, including rice. Climate change, particularly elevated CO2 (eCO2) alters the soil microbial community, but the alteration of AMF community has received little attention, partly because of inadequacy in understanding of AMF taxonomy. Therefore, an attempt was made to understand AMF community in paddy soil under long-term exposure (8 years) to eCO2 through sequencing 18S rRNA small subunit SSU based Illumina Miseq technique using the primer pair AML1/AML2. Changes in OTUs belonging to 23 AMF species were identified in the ambient (400 ± 10 μmol mol-1) and eCO2 (550 ± 20 μmol mol-1) conditions, respectively based on reads alignment using MaarjAM VT database. Moreover, principal coordinate (PCO) analysis clustered the related OTUs and suggested that long-term exposure of eCO2 suppressed the OTUs of Glomerales and encouraged the OTUs of Diversisporales. Overall, the present study indicates that long-term exposure of paddy soil to eCO2 (550 ppm) drastically reduced the commonly occuring AMF such as Claroideoglomus and Glomus species in sub-humid tropical condition.