Effects of long-term fertilization on arbuscular mycorrhizal fungal community in lime concretion black soil.

In agroecosystem, arbuscular mycorrhizal fungi have mutually beneficial symbiosis with roots of many crops. Meanwhile, this special fungal community is also affected by agricultural mana-gements such as fertilization. The objective of this study was to investigate the effects of long-term fertilization managements (no fertilizer, chemical fertilizer, chemical fertilizer combined with straw, chemical fertilizer combined with manure) on arbuscular mycorrhizal fungal community (AM fungal community) in lime concretion black soil, and to identify the indicator species in each fertilization regime. The most dominant arbuscular mycorrhizal fungal phyla in lime concretion black soil were Archaeosporaceae, Diversisporaceae, Gigasporaceae, Claroideoglomeraceae, Glomeraceae and Paraglomeraceae. The genus Paraglomus was strongly and significantly associated with the application of chemical fertilizer and organic fertilizer. Compared with the control, long-term application of chemical fertilizer greatly changed AM fungal community structure and resulted in the decrease of AM fungal diversity, and the addition of wheat straw further decreased the diversity, while the addition of manure could alleviate diversity loss resulted from chemical fertilization. Soil pH and dissolved organic carbon (DOC) were the main factors affecting the changes of AM fungal community. In summary, long-term application of chemical fertilizer combined with different organic materials had different impacts on soil AM fungal community structure and diversity. The combination of chemical fertilizer and manure would be more conducive to the maintenance of AM fungal diversity.