Fungal community composition and function but not diversity were significantly affected by continuous cropping and the interaction with sesame genotype

Abstract

Fungi are a substantial diverse group of soil microorganisms, and play a major role in soil and crop health. To investigate the effect of continuous cropping (CC) on sesame rhizosphere fungal community, this study analyzed fungal community through Illumina MiSeq technology. Fungal composition and function, but not diversity and richness, were significantly affected by CC and CC-genotype interaction. Short-term CC had dual effect on rhizosphere fungi that both beneficial fungi, like Chaetomium, Acidomelania, Tausonia, Rhodotorula, Humicola, and pathogenic fungi, like Aspergillus, Polyschema, Curvularia, Phoma, Dihymella and Epicoccum, were increased under CC. However, the specific species were varied among three genotypes, which may be the reason for their different response of plant pathogen and animal pathogen-plant pathogen-undefined saprotroph function to CC. As a result, the abundance of saprotroph-symbiotroph and dung saprotroph function decreased, whereas that of pathotroph-saprotroph-symbiotroph increased under short-term CC. These results provided basic knowledge about the changes of fungal community under short-term CC, but further investigation of the variation under long duration was still needed to fully understand continuous cropping obstacle.