SABATH methyltransferase can methylate small-molecule metabolites of plants to generate different products, and it plays a crucial role in plant growth and development as well as stress response. In this study, 13 SABATH genes distributed on five chromosomes of cucumbers were identified, and the synergistic effects among their domains, gene structures, conserved motifs, phylogenetic relationships, collinearity analysis, cis-acting elements, expression patterns, and plant growth-promoting rhizosphere bacteria (PGPR) were analyzed. The gene structure and conserved motifs of the same group of CsSABATH have similar intron numbers and conserved motifs. We detected 10 cis-elements in the promoter of the CsSABATH gene, indicating that they may be involved in different signaling pathways. qRT-PCR revealed the tissue-specific, drought and salt stress-responsive expression of the SABATH gene in cucumbers. Furthermore, we also verified that the expression level of CsaV3_6G046510 after inoculation with PGPR-GD17 bacteria under drought and salt stress was significantly lower than normal drought and salt dress, indicating that this gene may respond to PGPR and in abiotic stress play an important role. This study provides valuable insights into the molecular characteristics and evolutionary history of the SABATH gene family in cucumbers, laying a foundation for further analysis of the function of the CsSABATH gene in cucumbers.

Nano-titanium dioxide (nano-TiO₂) can alleviate oxidative damage in plants subjected to abiotic stress, interfere with related gene expression, and change metabolite content. Polylactic acid (PLA) microplastics can inhibit plant growth, induce oxidative stress in plant cells, and alter the biophysical properties of rhizosphere soil. In this study, untargeted metabolomics (LC-MS) and RNA-seq sequencing were performed on radish root cells exposed to nano-TiO₂ and PLA. The results showed that nano-TiO₂ alleviated the growth inhibition of radish roots induced by PLA. Nano-TiO₂ alleviated PLA-induced oxidative stress, and the activities of SOD and POD were decreased by 28.6% and 36.0%, respectively. A total of 1673 differentially expressed genes (DEGs, 844 upregulated genes, and 829 downregulated genes) were detected by transcriptome analysis. Metabolomics analysis showed that 5041 differential metabolites were involved; they mainly include terpenoids, fatty acids, alkaloids, shikimic acid, and phenylpropionic acid. Among them, phenylpropanoid biosynthesis as well as flavone and flavonol biosynthesis were the key metabolic pathways. This study demonstrates that nano-TiO₂ mitigates PLA phytotoxicity in radish via transcriptional and metabolic reprogramming of phenylpropanoid biosynthesis. These findings provide important references for enhancing crop resilience against pollutants and underscore the need for ecological risk assessment of co-existing novel pollutants in agriculture.

Polyvinyl chloride (PVC) is commonly employed as mulch in agriculture to boost crop yields. However, its toxicity is often overlooked. Due to its chemical stability, resistance to degradation, and the inadequacy of the recycling system, PVC tends to persist in farm environments, where it can decompose into microplastics (MPs) or nanoplastics (NPs). The radish (Raphanus sativus L.) was chosen as the model plant for this study to evaluate the underlying toxic mechanisms of PVC NPs on seedling growth through the integration of multi-omics approaches with oxidative stress evaluations. The results indicated that, compared with the control group, the shoot lengths in the 5 mg/L and 150 mg/L treatment groups decreased by 33.7% and 18.0%, respectively, and the root lengths decreased by 28.3% and 11.3%, respectively. However, there was no observable effect on seed germination rates. Except for the peroxidase (POD) activity in the 150 mg/L group, all antioxidant enzyme activities and malondialdehyde (MDA) levels were higher in the treated root tips than in the control group. Both transcriptome and metabolomic analysis profiles showed 2075 and 4635 differentially expressed genes (DEGs) in the high- and low-concentration groups, respectively, and 1961 metabolites under each treatment. PVC NPs predominantly influenced seedling growth by interfering with plant hormone signaling pathways and phenylpropanoid production. Notably, the reported toxicity was more evident at lower concentrations. This can be accounted for by the plant’s “growth-defense trade-off” strategy and the manner in which nanoparticles aggregate. By clarifying how PVC NPs coordinately regulate plant stress responses via hormone signaling and phenylpropanoid biosynthesis pathways, this research offers a scientific basis for assessing environmental concerns related to nanoplastics in agricultural systems.

微塑料（<5 mm）作为新型环境污染物, 广泛分布于水体、土壤及大气环境中, 对生态系统及人类健康构成严重威胁. 传统处理技术(如焚烧、填埋等)存在二次污染风险, 成本效益比低等缺点, 亟需开发绿色降解途径. 微生物具有分解高分子聚合物的代谢能力, 是微塑料降解的核心生物要素, 部分细菌和真菌已被证明能将其转化为环保的碳化合物. 在好氧与厌氧这两种典型氧化还原环境下的微生物群落结构、代谢途径及降解效率存在明显差异. 基于此, 本综述系统总结了微塑料的分布与来源, 及其物理化学性质对微生物的影响. 探讨了微生物在有氧与无氧条件下对微塑料的降解机制, 为开发高效生物降解技术, 制定微塑料污染控制策略提供重要的理论依据.

Photoperiod sensitivity significantly affects the reproductive process of plants. The CONSTANS, CONSTANS-LIKE, and TOC1 (CCT) genes play pivotal roles in photoperiod sensitivity and regulating flowering time. However, the function of the CCT gene in regulating flowering varies among different species. Further research is needed to determine whether it promotes or delays flowering under long-day (LD) or short-day (SD) conditions. CCT MOTIF FAMILY (CMF) belongs to one of the three subfamilies of the CCT gene and has been proven to be involved in the regulation of circadian rhythms and flowering time in cereal crops. In this study, 60 CCT genes in Chinese cabbage were genome-wide identified, and chromosomal localization, gene duplication events, gene structure, conserved domains, co-expression networks, and phylogenetic tree were analyzed by bioinformatics methods. The specific expression patterns of the BrCMF gene in different tissues, as well as the transcriptome and RT-qPCR results under different photoperiodic conditions, were further analyzed. The results showed that BrCMF11 was significantly upregulated in ebm5 under LD conditions, suggesting that BrCMF11 promoted flowering under LD conditions in Chinese cabbage. These findings revealed the function of the BrCCT gene family in photoperiod flowering regulation and provided a prominent theoretical foundation for molecular breeding in Chinese cabbage.

Organohalide-respiring bacteria (OHRB) facilitate the reductive dehalogenation of toxic halogenated compounds in the environment, which supports their growth and proliferation. Research conducted on OHRB has achieved notable advancements. However, given the intricacy of the ecosystem and the methodologies employed for microbial isolation, numerous constraints persist. Further exploration is imperative to elucidate the physiological characteristics, ecological functions, and technological applications of OHRB. This study aimed to evaluate the outcomes and insights of prior research via a bibliometric analysis of three obligate OHRB genera—Dehalococcoides, Dehalobacter, and Dehalogenimonas—over a three-decade period from 1994 to 2024, based on the Web of Science (WOS) database. The results show that research on these three bacterial genera has advanced in sequence since the initiation of studies in this field. The research area encompasses the identification and isolation of novel OHRB species, the gene sequencing of related enzymes, and the role of microorganisms in the remediation of environmental pollutants, reflecting a gradual transition from individual investigations of OHRB to the applications of microorganisms in remediating complex environmental pollution. This study systematically reviewed the past research history of this field and conducted an in-depth analysis of research hotspots. The integration of this analysis with technological development trends and practical application requirements provides a theoretical basis and innovative concepts for future research directions in the field of ecological environment restoration.