Genetic and environmental factors influence the growth and quality of medicinal plants. In recent years, rhizosphere microorganisms have also emerged as significant factors affecting the quality of medicinal plants. This study aimed to identify Schisandra resources with high lignan content and analyze the microbial diversity of the rhizosphere soil. High-performance liquid chromatography was used to measure the lignan content in nine Schisandra fruits. High-throughput sequencing was used to analyze the 16S rDNA sequences of rhizosphere bacteria to identify bacterial species diversity. The total lignan content of the nine Schisandra resources ranged from 9.726 mg/g to 14.031 mg/g, with ZJ27 having the highest content and ZJ25 the lowest. Among the six lignan components, Schisandrol A had the highest content, ranging from 5.133 mg/g to 6.345 mg/g, with a significant difference between ZJ25, ZJ27, and other resources (p < 0.05). Schizandrin C had the lowest content, ranging from 0.062 mg/g to 0.419 mg/g, with more significant differences among the resources. A total of 903,933 sequences were obtained from the rhizosphere soil of the nine Schisandra resources, clustered into 10,437 OTUs at a 97% similarity level. The dominant bacterial phyla were Actinobacteriota, Acidobacteriota, Proteobacteria, Chloroflexi, Gemmatimonadota, and Verrucomicrobiota. The dominant bacterial genera were Candidatus_Udaeobacter, Candidatus_Solibacter, RB41, Bradyrhizobium, Gaiella, and Arthrobacter. ZJ27 is the Schisandra resource with the highest lignan content, and the rhizosphere bacteria of Schisandra are rich in diversity. Schisandra B is negatively correlated with Bryobacter, Candidatus_Solibacter, and unnamed genera of Gaiellales.

The seasonal changes in environmental conditions can alter the growth states of host plants, thereby affecting the living environment of endophytes and forming different endophytic communities. This study employs Illumina MiSeq next-generation sequencing to analyze the 16SrRNA and ITS rDNA of endophytes in 24 samples of Actinidia arguta stem tissues across different seasons. The results revealed a high richness and diversity of endophytes in Actinidia arguta, with significant seasonal variations in microbial community richness. This study identified 897 genera across 36 phyla for bacteria and 251 genera across 8 phyla for fungi. Notably, 69 bacterial genera and 19 fungal genera significantly contributed to the differences in community structure across seasons. A distinctive feature of coexistence in the endophytic community, both specific and conservative across different seasons, was observed. The bacterial community in winter demonstrated significantly higher richness and diversity compared to the other seasons. Environmental factors likely influence the optimal timing for endophyte colonization. Solar radiation, temperature, precipitation, and relative humidity significantly impact the diversity of endophytic bacteria and fungi. In addition, seasonal variations show significant differences in the nutritional modes of fungal endophytes and the degradation, ligninolysis, and ureolysis functions of bacterial endophytes. This study elucidates the potential role of endophytes in assisting Actinidia arguta in adapting to seasonal changes and provides a theoretical basis for further exploration of functional microbial strains.

SO₂ plays an important role in wine fermentation, and its effects on wine aroma are complex and diverse. In order to investigate the effects of different SO₂ additions on the fermentation process, quality, and flavor of ‘Beibinghong’ ice wine, we fermented ‘Beibinghong’ picked in 2019. We examined the fermentation rate, basic physicochemical properties, and volatile aroma compound concentrations of ‘Beibinghong’ ice wine under different SO₂ additions and constructed a fingerprint of volatile compounds in ice wine. The results showed that 44 typical volatile compounds in ‘Beibinghong’ ice wine were identified and quantified. The OAV and VIP values were calculated using the threshold values of each volatile compound, and t the effect of SO₂ on the volatile compounds of ‘Beibinghong’ ice wine might be related to five aroma compounds: ethyl butyrate, ethyl propionate, ethyl 3-methyl butyrate-M, ethyl 3-methyl butyrate-D, and 3-methyl butyraldehyde. Tasting of ‘Beibinghong’ ice wine at different SO₂ additions revealed that the overall flavor of ‘Beibinghong’ ice wine was the highest at an SO₂ addition level of 30 mg/L. An SO₂ addition level of 30 mg/L was the optimal addition level. The results of this study are of great significance for understanding the effect of SO₂ on the fermentation of ‘Beibinghong’ ice wine.