Crop replanting leads to soil degradation and soil productivity reduction, which is a challenge for sustainable agricultural development. We previously found that silicon fertilizers combined with additional microbial agents are an effective means to alleviate problems that occur in a variety of Chinese lily during replanting, but little is known about the changes in microbial structure during this process. In the present study, we applied four treatments: CK (control), SF (silicon fertilizer), MF (microbial agents), and SMF (combination of silicon fertilizer and microbial agents). We treated the soil constantly for three years and investigated the bacterial community structure and some specific microbial groups in the soil of the lily root zone using 16S rRNA high-throughput sequencing analysis. The results showed that silicon fertilizer and microbial agent treatment significantly improved the growth status of the plants and changed the diversity and structure of the bacterial community in the soil. The genus Pseudomonas significantly increased in the SF treatment, and the phylum Actinobacteria and the genera Nordella, Devosia, and Rhodoplanes significantly increased in the SMF treatment. The genera Nordella, Pedomicrobium, and Chthoniobacter correlated with the seedling index or available silicon content. In addition, the two genera Gaiella and Nocardioides were the key species linking the bacterial community in the soil. The soil physicochemical properties played an important role in restoring the soil bacterial community structures. In conclusion, silicon fertilizer and microbial agents changed the diversity and structure of the bacterial community. Under the fertilizer supplement model, the enrichment of the phylum Actinobacteria and the genus Pseudomonas played an important role in improving soil health and alleviating CRPs in lilies. In addition, organic matter, available phosphorus, available potassium, and available silicon were found to be the most important factors that have a great impact on the restoration of bacterial community structures.

In the present study, five new wood-inhabiting fungal species, Conferticium albocremeum (Stereaceae, Russulales), Dendrocorticiopsis luteoalba (Punctulariaceae, Corticiales), Eichleriella biluoxueshanensis (Auriculariaceae, Auriculariales), Gloeohypochnicium yunnanense (Incertae sedis, Russulales), and Punctularia nigrodontea (Punctulariaceae, Corticiales), collected from southern China, are proposed based on a combination of morphological features and phylogenetic evidence. Conferticium albocremeum is characterized by membranaceous and smooth basidiomata with white to cream surface and ellipsoid and verrucose basidiospores (9–11 × 5–7 µm); Dendrocorticiopsis luteoalba is characterized white to buff, membranaceous basidiomata and ellipsoid, thin-walled and smooth basidiospores (7–8 × 4.5–5.5 µm); Eichleriella biluoxueshanensis is characterized by coriaceous and grandinioid basidiomata with buff to cinnamon-buff hymenophore and allantoid, thin-walled basidiospores (13.5–17.5 × 7–9 µm); Gloeohypochnicium yunnanense is characterized by buff to cream, coriaceous and smooth basidiomata and globose, thick-walled and warted basidiospores (10–12 × 10–11.5 µm), and Punctularia nigrodontea is characterized by resupinate to effused-reflexed basidiomata and ellipsoid, thin-walled and smooth basidiospores (8.5–10 × 5–6 µm). Sequences of the internal transcribed spacers (ITS) and the large subunit (nLSU) of the nuclear ribosomal DNA (rDNA) markers of the studied samples were generated. Phylogenetic analyses performed based on the ITS+nLSUrDNA gene regions with the maximum likelihood, maximum parsimony, and Bayesian inference methods revealed that five new species belong to the genera Conferticium, Dendrocorticiopsis, Eichleriella, Gloeohypochnicium, and Punctularia. Descriptions, illustrations, phylogenetic analysis results, and a comparison with closely related taxa of the five new species are provided.

Lanzhou Lily(Lilium davidii) var. unicolor, which is also known as sweet lily in China, is used as a type of food. This lily is distributed in narrow regions, propagates asexually, cultivates perennially, and cultivates commonly in serious consecutive replant problems (CRPs). Soil fumigation is commonly used to control soil-borne disease to alleviate crops’ consecutive replant problems (CRPs). However, due to the improper fumigation application, it is common to cause chemical hazard to crops. In this study, we designed a two-factor experiment to explore the bacterial and fungal community structure and some specific microbial groups in the lily rhizosphere soil after chemical versus bacterial fertilizer treatments, by using a metagenomic analysis of the treated soils. The results showed that metham-sodium soil fumigation (SMF treatment) significantly decreased plant growth, as well as it significantly decreased both soil fungal diversity and abundance at the OTUs levels, while Special 8™ microbial fertilizer supplement (MF treatment) significantly improved plant growth and increased fungal diversity and abundance. Under FM treatment, Chao1 richness and Shannon’s diversity increased by 6.70% and 35.09% compared to CK (no treatment). However, the bacterial diversity and abundance were not significantly changed among these treatments. The fungal and bacterial community structure were different in all treatments. In SMF treatment, the pathogenic fungal species Fusarium oxysporum increased compared to CK, but it significantly decreased in MF treatment; in MF and MMF treatments, some beneficial bacteria groups such as the bacterial phylum Proteobacteria and its member genus Sphingomonas, as well as the fungal genus Mortierella, increased compared to CK and SFM treatments, but the harmful bacterial genera Gemmatimona was decreased, as well as the harmful fungal genus Cryptococcus. Thus, we concluded that under chemical fumigation conditions, both fungal diversity loss and overall microorganism reduction, which impair multiple ecosystem function, in conjunction with the increase of harmful fungal species such as Fusarium oxysporum, are causes for soil degradation. On the other hand, under microbial fertilizer supplement, it was the fungal diversity increase, as well as these beneficial microorganisms groups’ accumulation, together with those harmful groups’ depletion, played important roles in restoring and improving soil health that suffered from the chemical fumigant hazard. In addition, the bacterial phylum Proteobacteria and its member genus Sphingomonas are involved in soil health recovery and promotion. The results also emphasized that whether soil is chemically fumigated or not, beneficial microorganism supplementary is effective in ensuring soil productivity.

Background: Biological fumigation, a potential alternative to chemical fumigation, shows a wide range of prospective applications. In this study, we carried out biological fumigation experiments to evaluate its effect on alleviating consecutive cropping problems (CRPs) when compared with chemical fumigation. Methods: We designed five treatments, namely, CR (no treatment), LN (chemical fumigation with lime nitrogen), Ta (fumigation with marigold), Ra (fumigation with radish), and Br (fumigation with mustard), for soils for replanting eggplant and measured the crop’s growth status, soil bacterial and fungal communities, and soil physicochemical properties. Results: The results showed that the Br and Ra treatments formed similar microbial communities, while the Ta treatment formed unique microbial communities. The genera Olpidiomycota and Rozellomycota could be used as indicator species for the transformation process of soil microbial communities after the Br and Ta treatments, respectively. When compared with the CR and LN treatments, the soil’s physicochemical properties were optimized under the Br treatment, and the soil organic matter content increased by 64.26% and 79.22%, respectively. Moreover, under the Br treatment, the soil’s biological properties enhanced the bacterial and fungal alpha diversity, and the saprotrophic fungi increased with the depletion of pathotrophic fungi, while some specific probiotic microorganisms (such as Olpidiomycota, Microascales, Bacillus, etc.) were significantly enriched. In contrast, under the Ta treatment, soil nutrient levels decreased and the soil’s biological indices deteriorated, whereas the bacterial diversity decreased and the pathogenic fungi increased. Conclusions: Among these three biological fumigation methods, the Br pre-treatment was the best way to alleviate the crop’s CRPs and may be a good substitute for chemical fumigation in some situations. However, the Ta treatment also had some risks, such as the loss of land quality and reduced productivity.

The Trihelix transcription factor family, characterized by its unique triple-helix structure (helix-loop-helix-loop-helix), plays a significant role in plant growth, development, and responses to various abiotic stresses. Potato (Solanum tuberosum L.), as a globally important food crop, experiences significant impacts on its growth and yield due to abiotic stresses such as drought, low temperature, and salt stress. Although the functions of Trihelix transcription factors have been extensively studied in various plants, systematic analysis in potatoes remains relatively scarce. This study aims to comprehensively identify the Trihelix gene family in potatoes through bioinformatics methods and analyze their expression patterns under abiotic stresses to reveal the potential functions of this gene family in potato growth, development, and stress responses. Through genome database searches and BLAST comparisons, 35 StTrihelix genes were identified in potatoes, and phylogenetic, gene structure, functional motif, and cis-acting element analyses were conducted. The expression patterns of these genes in different tissues and under low-temperature and drought stresses were analyzed using qRT-PCR technology. Additionally, the nuclear localization of StTrihelix30 was verified through subcellular localization experiments. The results indicate that the 35 StTrihelix genes are unevenly distributed across 12 chromosomes and can be classified into five subfamilies: GT-1, GT-2, GTγ, SH4, and SIP1. Gene structure and functional motif analyses revealed high conservation within the same subfamily. Cis-acting element analysis showed that these genes are closely related to hormone responses, stress responses, and growth and development processes. Tissue expression analysis showed that StTrihelix4 is highly expressed in stamens, while StTrihelix13 is highly expressed in roots. qRT-PCR results indicated that most StTrihelix genes are significantly upregulated under low-temperature and drought stresses. This study systematically identified the Trihelix gene family in potatoes and revealed its important role in abiotic stress responses. It provides new insights into the functions of the Trihelix transcription factor family in potato growth, development, and stress adaptation, offering theoretical references for stress-resistant potato breeding.