Flowering is critical to the success of plant propagation. The MYB family transcription factor CIRCADIAN CLOCK-ASSOCIATED1 (CCA1) is an essential component of the core loop of the circadian clock and plays a crucial role in regulating plant flowering time. In this study, we found that photoperiod affects the expression pattern and expression level of BcCCA1, which is delayed flowering time under short-day conditions in Pak-choi [Brassica campestris (syn. Brassica rapa) ssp. chinensis]. We detected overexpression and silencing of BcCCA1 in Pak-choi, resulting in delayed and promoted flowering time, respectively. Furthermore, we also discovered that FLOWERING LOCUS C (BcFLC) and SUPPRESSOR OF CONSTANS1 (BcSOC1) were expressed significantly differently in BcCCA1 overexpression and silencing plants compared with control plants. Therefore, we further investigated the interaction relationship between BcCCA1, BcFLC, and BcSOC1, and the results showed that BcCCA1 and BcFLC as a complex interacted with each other. Moreover, both BcCCA1 and BcFLC can directly bind to the promoter of BcSOC1 and repress its transcription, and BcCCA1 can form a complex with BcFLC to enhance the transcriptional inhibition of BcSOC1 by BcFLC. This study reveals a new mechanism by which the circadian clock regulates flowering time.

Rice is a staple food for more than half of the global population, but its production is threatened by insect pests such as planthoppers, stem borers, leafhoppers, and defoliators. The widespread use of chemical pesticides has raised concerns regarding environmental contamination, pest resistance, and negative effects on beneficial arthropods. This review examines the role of biological control and habitat management in sustainable rice pest management. It highlights the diversity and ecological roles of natural enemies, including parasitoid wasps, mirid bugs, ladybird beetles, and spiders, which help suppress pest populations in rice ecosystems. Key habitat management approaches, such as conservation biological control, ecological engineering, banker plant systems, flower strips, and the preservation of non-crop habitats, are discussed for their capacity to enhance the abundance and effectiveness of natural enemies. The review also considers integrating these approaches into IPM programs to reduce reliance on pesticides while maintaining crop productivity. Evidence from rice-growing regions demonstrates the effectiveness of habitat-based strategies in improving pest suppression and strengthening ecosystem resilience. However, challenges related to landscape complexity, farmer adoption, long-term implementation, and the need for a clear roadmap for future landscape-scale entomological research remain. Future research should focus on optimizing habitat management practices and integrating ecological approaches with modern agricultural technologies to support sustainable rice production.

The primary domain/leucine zipper (bZIP) transcription factor, Elongated Hypocotyl (HY5), is crucial for the photomorphogenesis of seedlings. Here, we identified BcHY5 as a regulator of hypocotyl length from the non-heading Chinese cabbage (NHCC) variety ‘Suzhouqing’, which encoded a protein comprised 164 amino acid residues. Ectopic expression of BcHY5 in Arabidopsis shortens the length of the hypocotyl. Additionally, we discovered a protein called BcBBX24 containing the B-BOX (BBX) domain, which is the interacting partner of BcHY5. Yeast two-hybrid (Y2H), bimolecular fluorescence complementation (BiFC) and GST pull-down assays revealed that BcHY5 interacted with BcBBX24. Additionally, by physically binding to the promoter of BcHY5, BcBBX24 inhibited the transcriptional activity of BcHY5. Therefore, our findings reveal a transcriptional mechanism through which light response occurs in NHCC seedlings, where BcHY5 can interact with BcBBX24 and BcBBX24 can prevent BcHY5 transcription.

Leaves are the primary organs for plant photosynthesis, and their flat, symmetric morphology is crucial for plant growth and development. The LBD family transcription factor ASYMMETRIC LEAVES 2 (AS2) plays a central role in the establishment of leaf polarity. In this study, we cloned the BcAS2 gene from the non-heading Chinese cabbage cultivar “NHCC001” and successfully generated overexpression strains through genetic transformation. Phenotypic analysis revealed that overexpression of BcAS2 led to significant upward curling of leaves in non-heading Chinese cabbage. Additionally, we found that the expression of BcPHB, a gene associated with leaf adaxial polarity development, was significantly up-regulated in BcAS2-overexpressing plants compared to controls. This interaction was further confirmed through yeast one-hybridization (Y1H), dual-luciferase reporter assays, and electrophoretic mobility shift assay (EMSA), all of which demonstrated that BcAS2 directly binds to the GATA-motif site of the BcPHB promoter and promotes its transcription. Functional validation via overexpression and silencing of BcPHB confirmed its role in regulating adaxial polarity development in non-heading Chinese cabbage leaves. This study elucidates the molecular mechanism of the BcAS2-BcPHB pathway in regulating leaf polarity in non-heading Chinese cabbage, providing a theoretical foundation for morphological improvement breeding.

Chloroplast-genome variation below the species level remains insufficiently characterized in Brassica, because most previous studies have relied on only one or a few representative plastomes. To determine whether dense within-subspecies sampling could reveal localized variation obscured by broader comparisons, we sequenced and assembled complete chloroplast genomes from 10 morphologically diverse varieties of Non-heading Chinese cabbage (NHCC; Brassica campestris [syn. Brassica rapa] ssp. chinensis) and placed their codon-usage patterns in the context of 15 Brassica plastomes. The NHCC plastomes were highly conserved in genome size (153,480–153,533 bp), GC content (36.36–36.39%), gene content, gene order, and quadripartite structure. Nevertheless, locus-level comparisons showed that the limited sequence variation was concentrated in a small number of regions. Six protein-coding loci and four intergenic spacers exhibited relatively elevated nucleotide diversity, and explicit counts of variable sites and internal indel blocks further characterized the sequence differences underlying these values. These loci represent candidate regions for population-level validation and potential molecular-marker development rather than confirmed variety-specific markers. In the broader comparison, mean ENC varied only from 45.15 to 45.49 among the 15 plastomes, indicating a highly conserved codon-usage background characterized by a general preference for A/U-ending synonymous codons. Eight codons—ACU, AGA, CAA, CUA, GCU, GGU, GUA, and UGU—were consistently recovered as putative optimal codons, although statistical support for ACU and GGU was restricted to a subset of accessions. PR2 analysis revealed imbalances within complementary nucleotide pairs rather than an overall preference for G/C-ending codons. Thus, the principal contribution of this study is the fine-scale localization of plastome variation through dense sampling within NHCC, providing candidate regions for subsequent diversity assessment and marker validation in independently sampled individuals.