The potato dry rot disease caused by Fusarium spp. seriously reduces potato yield and threatens human health. However, potential biocontrol agents cannot guarantee the stability and activity of biocontrol. Here, 18 synthetic microbial communities of different scales were constructed, and the synthetic microbial communities with the best biocontrol effect on potato dry rot disease were screened through in vitro and in vivo experiments. The results show that the synthetic community composed of Paenibacillus amylolyticus, Pseudomonas putida, Acinetobacter calcoaceticus, Serratia proteamaculans, Actinomycetia bacterium and Bacillus subtilis has the best biocontrol activity. Metabolomics results show that Serratia protoamaculans interacts with other member strains to produce caproic acid and reduce the disease index to 38.01%. Furthermore, the mycelial growth inhibition after treatment with caproic acid was 77.54%, and flow cytometry analysis showed that the living conidia rate after treatment with caproic acid was 11.2%. This study provides potential value for the application of synthetic microbial communities in potatoes, as well as the interaction mechanisms between member strains of synthetic microbial communities.

The application of herbicides to arable land is still the most effective and accepted method to protect plants from weeds. Extensive use of chemicals in conventional agricultural practices has resulted in continuous and serious environmental pollution. Flurochloridone (FLC) is a monophenyl pyrrolidinone selective herbicide that is commonly used to inhibit weeds that occur during the growth of potatoes. In recent years, research on the toxicity of FLC has gradually increased. However, it is relatively rare to analyze the role of FLC by studying the composition of soil microorganisms. Therefore, we used NGS methods to identify the fungal community structure of the low content soil (LS) and high content soil (HS) samples in this study. Subsequently, we identified the fungal community and composition differences of these two group samples using the statistical analysis. Despite the variances of fungal community and composition across the different samples within the group, the fungal composition of the LS samples and the HS samples. LS samples were predominated by Ascomycota, while the HS samples were predominated by Mortierellomycota and Basidiomycota. The major species in the LS samples were Plectosphaerellacucumerina and Trichocladiumasperum, whereas the dominant species in the HS samples were Epicoccum nigrum and Cladosporium chasmanthicola. These results suggested that the LS samples and the HS samples had different rhizosphere soil fungal community and composition changes resulting from implementation of FLC in potato growing areas.

The potato (Solanum tuberosum), an important component of global food security, often faces threats from various diseases during its growth process, especially potato anthracnose (Colletotrichum coccodes), which severely affects crop yield and quality. In this study, we successfully isolated and identified two bacteria with potential for biological control, (Pantoea agglomerans) and (Bacillus subtilis). The experimental results indicate that the bacterial suspensions of strains JZ-1-1-1 and JZ-2-2-2 had a significant inhibitory effect on the pathogen ZL-7, with the inhibition rate of JZ-1-1-1 reaching as high as 55.21%. The inhibition rate of JZ-2-2-2 was 53.48%. When these two strains were mixed at a 4:6 ratio, the inhibitory effect on pathogenic bacteria was even more significant, reaching 68.58% inhibition. In addition, the composite microbial community produced biofilms with their yield gradually increasing within 24 h and showing a slight decrease after 72 h. The efficacy test further indicated that the composite bacterial suspension was highly effective in controlling the spread of lesions, with an efficacy rate as high as 81.40%. In the analysis of defense enzyme activity, peroxidase (POD) and superoxide dismutase (SOD) levels peaked on day seven, while the composite bacterial suspension significantly reduced malondialdehyde (MDA) and polyphenol oxidase (PPO) activity. Quantitative real-time PCR confirmed that these two strains effectively colonized the surface of potato tubers. In summary, this study provides an important theoretical basis and practical guidance for the application of biological methods for the prevention and control of potato anthracnose.

Chinese sacbrood virus (CSBV) is a serious threat to eastern honeybees (Apis cerana), especially larvae. However, the pathological mechanism of this deadly disease is remains unclear. Here, we employed an mRNA-seq and sRNA-seq approach in healthy and CSBV-infected 3 ^rd Apis cerana larval. Gene ontology (GO) and KEGG analysis of 203 differentially expressed genes showed that CSBV infection affected host development by up-regulating the expression of larval cuticle proteins, such as larval cuticle proteins A1A and A3A, resulting in elevated susceptibility to CSBV. In addition, viral infection not only affected the expression of serine protease related to the melanization pathway and but also altered fatty acid metabolism and biosynthesis, thus progressed to disturb host immune response. Interestingly, GO annotation and KEGG analysis on target genes of CSBV-specific siRNA (vsiRNAs) showed that serine/threonine kinase activity and serine-type endopeptidas as well as fatty acid biosynthesis were significantly enriched (P < 0.05). Among these vsiRNAs, vsiRNA-1441 with relatively high expression targeted extracellular serine/threonine protein kinase. This study provides new evidence that CSBV attacks a distinct immune response pathway and mediates the expression of cuticle protein to gain the more chance of proliferation.