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Fungi play an essential role in recovering the quality and fertility of soil. There is a limited understating of the complex response of fungal diversity to different organic materials in clay loam soil. Here, we report the response of soil fungi toward the short-term application of manure (M), sugarcane straw (S), and sugarcane straw plus manure (MS), including no organic material control (CK) at two different time points (50 and 100 days after application). Illumina sequencing was used to examine the fungal communities. Our results reveal a significant shift among the soil fungal community structure associated with each organic material application. After both time points, amendments—especially M and MS—decreased the fungal richness and stimulated the copiotrophic fungal group (Ascomycota) compared to the control soil (CK) and S-amended soil. On the contrary, as compared to the M and MS-amended soils, the CK and S-amended soils at both time points increased the fungal richness and stimulated the oligotrophic fungal groups. Organic material use, especially M and MS, showed variable results regarding pathogenic fungi enhancing the abundance of Lophodermium and Cercophora and decreasing Fusarium. Concerning the abundance of plant-beneficial fungi, Mortierella was reduced, and Podospora was increased by M and MS input. FUNGuild showed that the amendment of organic materials efficiently declined the abundance of endophytes and plant pathogens, but also enhanced the animal pathogens in terms of abundance with respect to CK at two time points. This study could be useful to provide a novel understanding of the management of soil-borne pathogens by organic amendments for the sustainable production of short-term crops.

Cyanobacteria play an important role in maintaining soil fertility in rice fields. Some cyanobacterial members can grow heterotrophically under dark conditions, which might be an important trait for the survival of cyanobacteria during the drained period after harvest. This study aimed to elucidate the heterotrophic growth of cyanobacteria and the microbial loop mediated by cyanophages (cyanobacteria-cyanophagesdissolved organic carbon) in soil using carbon-13 ( 13 C)-labeled dried callus cells as a model material of plant residues. This study used the stable isotope probing (SIP) method coupled with denaturing gradient gel electrophoresis (DGGE). Although heterotrophic growth of cyanobacteria in soil was not observed, the phage-mediated microbial loop in the transformation of callus carbon was elucidated from the detection of 13 C-labeled g20 genes in the heaviest fractions (buoyant density: 1.754 g mL À1). The closest relatives of eleven sequenced DGGE bands from the heaviest fractions were uncultured cyanophage g20 clones that had been obtained from rice field soils in Japan. Proliferation of bacteriophages having cyanophage-related g20 genes with no detectable heterotrophic growth of cyanobacteria strongly indicates that bacteriophages having these g20 genes infected bacteria other than cyanobacteria.

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