Community composition of rhizosphere fungi as affected by Funneliformis mosseae in soybean continuous cropping soil during seedling period

Weiguang Jie1, 2, Jixiang Lin1, Na Guo1, 2, Baiyan Cai3, and Xiufeng Yan1*
Arbuscular mycorrhizal (AM) fungi can enhance plant resistance particularly against soil-borne pathogenic fungi. However, little is known about the effects of Funneliformis mosseae on the community composition of rhizosphere fungi in soybean (Glycine max [L.] Merr.) continuous cropping soil. Here, the disease index of soybean root rot was analyzed, and high throughput sequencing technology was applied to investigate whether F. mosseae could change the composition of fungal communities in the rhizosphere of continuous cropping soybean during seedling period. The results indicated that the disease index of soybean root rot decreased significantly after inoculation of F. mosseae. The root rot disease index was also affected by the increasing of continuous cropping regimes. Furthermore, the relative abundance of fungal community in soybean rhizosphere soil and root samples was influenced after inoculation. Ascomycota was the dominant phylum in most samples. Basidiomycota was the second dominant phylum in all the soil samples, but Olpidiomycota was the second phylum in most root samples. At the genus level, both inoculation and continuous cropping regimes had significant effects on the dominant genus and their relative abundances in all the samples. The relative abundance of some plant pathogenic fungi such as Fusarium in the inoculated root samples was lower than those in the non-inoculated root samples in the same continuous cropping regime. The results can provide new insights into the interactive effects of AM fungi and rhizosphere fungi, and also provide theoretical evidence on biological solutions to alleviate the obstacles of soybean continuous cropping.
Keywords: Continuous cropping, fungal communities, Glycine max, Funneliformis mosseae, high throughput sequencing, soybean.
1Northeast Forestry University, Alkali Soil Natural Environmental Science Center, Ministry of Education, Harbin 150040, China.*Corresponding author (xfyan@nefu.edu.cn). 2Heilongjiang East University, Department of Food and Environment Engineering, Harbin 150066, China.3Heilongjiang University, College of Life Sciences, Harbin 150080, China.