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While confronted with unfavorable growth conditions, bacteria may transform into the dormant state, such as viable but nonculturable (VBNC) state, which is a reversible state characterized by low metabolic activity and lack of division. These dormant cells can be reactivated through the influence of the resuscitation promoting factor (Rpf) family, which are classified as autocrine growth factors and possess peptidoglycan hydrolase activities. To date, with the significant resuscitation or growth promotion ability of Rpf, it has been extensively applied to increasing bacterial diversity and isolating functional microbial species. This review provides a comprehensive analysis of the distribution, mode of action, and functional mechanisms of Rpf proteins in various bacterial species. The aim is to create opportunities for decoding microbial communities and extracting microbial resources from real samples across different research fields.

Key points Degradable mulching film alter the diversity of cotton non-rhizosphere soil fungi. Degradable mulching film alter the soil microbial composition of cotton. Degradable mulching film dose not alter the diversity of cotton rhizosphere fungi. Degradable mulching film dose not alter the diversity of cotton soil bacteria.

The Baijiu-making microbiota has an important role in the alcohol production, flavor, and character of Baijiu. 16S rRNA gene sequencing revolutionized the understanding of Baijiu-making microbiota. In this study, nine phyla, 23 classes, 49 orders, 99 families, and 201 genera were detected in pit muds (PMs) by 16S rRNA gene sequencing. Firmicutes and Bacteroidetes predominated (>99%). At the order level, Clostridiales, Bacteroidales, and Bacillales predominated (>92%). At the genus level, Hydrogenispora, Petrimonas, Proteiniphilum, and Sedimentibacter predominated. The pure culture of Baijiu-making prokaryotes was essential to elucidating the role of these microbes in the fermentation of Baijiu. According to the theory of microbial culturomics, a culturing approach with multiple culture conditions was adopted, combining 16S rRNA gene sequencing. We identified 215 prokaryotic strains, which were assigned to 66 species, 41 genera, four phyla, and 19 potential new species. Gas conditions were key factors in culturomics. In addition, culturomics significantly increased the number of species isolated from the fermentation PM compared with previous reports. With culturomics, the diversity spectrum of culturable bacteria in the PM was increased 273.33% at the genus level. This study confirms the complementary role of culturomics in the exploration of complex microbiota.

Cucumber downy mildew (CDM) is a destructive plant disease caused by the air-borne oomycete pathogen Pseudoperonospora cubensis. CDM causes severe yield reduction of cucumber and significant economic losses. Biocontrol is a promising method to control CDM with the advantage of being beneficial to sustainable agricultural development. However, until now, no reviews of biocontrol of CDM have been reported. The objective of this review is to more comprehensively understand the biocontrol of CDM. In this review, the biological characteristics of P. cubensis are introduced, and strategies for screening biocontrol agents to suppress CDM are recommended. Then the current biocontrol agents, including fungi such as Trichoderma and biocontrol bacteria such as Bacillus, which possess the ability to control CDM, and their control characteristics and ability against CDM are also summarized. The potential mechanisms by which these biocontrol agents prevent CDM are discussed. Finally, several suggestions for future research on the biocontrol of CDM are provided.

Clonostachys rosea is an important mycoparasite, with great potential for controlling numerous plant fungal diseases. Understanding the mechanisms and modes of action will assist the development and application of this biocontrol fungus. In this study, the highly efficient C. rosea 67-1 strain was marked with the green fluorescent protein (GFP), and the transformant possessed the same biological characteristics as the wild-type strain. Fungal interactions with Botrytis cinerea during co-culture and encounter on tomato leaves were assessed by fluorescence confocal and electron microscopy. The results indicated that once the two fungi met, the hyphae of C. rosea grew alongside those of B. cinerea, then attached tightly to the host and developed special structures, via which the biocontrol fungus penetrated the host and absorbed nutrients, eventually disintegrating the cells of the pathogen. Mycoparasitism to B. cinerea was also observed on tomato leaves, suggesting that C. rosea can colonize on plants and act following the invasion of the pathogenic fungus.