Qin Yang

WRKY transcription factors play crucial roles in plant growth, development, and stress responses. However, their systematic evolution and functions within the genus Rubus remain incompletely understood. In this study, genome-wide identification, evolutionary analysis and functional characterization of the WRKY gene family were conducted in five Rubus species. A total of 37–67 members were identified and classified into three groups by phylogenetic analysis. The collinearity result, gene family expansion and contraction analyses revealed a contraction trend within the Rubus lineage compared with the outgroup sweet cherry. Promoter cis-acting element analysis predicted widespread involvement of these genes in hormone and stress responses. Expression profiling revealed tissue-specific patterns among WRKY genes, with most members down-regulated during fruit development and differentially regulated by biotic and abiotic stresses. Further correlation analysis and experimental validation were focused on RiWRKY48 in red raspberry (Rubus idaeus L.). This protein was localized to the nucleus and lacked transcriptional activation activity. Combined in silico modeling (AlphaFold3) and dual-luciferase reporter assays revealed that RiWRKY48 may repressed the promoter activity of RiUFGT4, a key anthocyanin biosynthetic gene, suggesting a putative interaction with the W-box element. In summary, this study systematically characterized the evolutionary features of the Rubus WRKY family and provided evidence for a potential regulatory role of RiWRKY48 in anthocyanin biosynthesis through modulation of RiUFGT4 promoter activity. These findings provided new insights into the regulatory roles of WRKY transcription factors in fruit quality development in Rubus species.

Low light is a major environmental constraint that limits crop productivity by restricting photosynthetic carbon assimilation and disrupting photosynthetic function. Nitric oxide (NO) is an important signaling molecule involved in plant stress responses; however, its role in regulating photosystem stability under low-light conditions remains unclear. In this study, tomato seedlings were treated with the NO donor sodium nitroprusside (SNP) and the NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO) to investigate the effects of NO-related treatments on growth, photosynthetic performance, photosystem function, electron transport, ROS accumulation, and antioxidant defense under low-light conditions. Low light markedly suppressed growth and impaired the photochemical activities of both photosystem II (PSII) and photosystem I (PSI), as indicated by decreases in the maximum quantum efficiency of PSII (Fv/Fm), the maximal P700 oxidation capacity (Pm), and electron transport rates, together with enhanced reactive oxygen species (ROS) accumulation. Exogenous NO application significantly improved photosystem performance under low-light conditions. NO enhanced PSII and PSI photochemical performance, improved excitation energy distribution, and restored photosynthetic electron transport, while strengthening antioxidant enzyme activities, thereby reducing excitation pressure and oxidative damage. In contrast, PTIO treatment aggravated photosystem impairment under low light. These findings indicate that NO contributes to maintaining photosystem function and photosynthetic electron transport under low-light conditions, highlighting its potential role in improving low-light tolerance in tomato.

Background/Objectives: Flower bud morphogenesis is a critical developmental phase during which blueberry transitions from vegetative to reproductive growth, yet the transcriptome dynamics and regulatory networks within buds during this process have not been systematically characterized. Methods: Terminal buds of the rabbiteye blueberry ‘Brightwell’ were sampled at six time points spanning from summer shoot cessation to bud swelling and dormancy entry. RNA sequencing, trend clustering, and Pearson correlation network analyses were performed to identify potentially important genes and regulatory relationships. Results: A total of 26,302 differentially expressed genes were identified, with a major transcriptomic shift at week 15. From four major expression trends, 1050 candidate genes were selected, including 176 flowering-related genes, 770 transcription factors, and 277 hormone-related genes. Photoperiod and vernalization pathway genes (COLs, VRN1, etc.) were predominantly down-regulated, whereas age pathway genes (SPLs) and MADS-box flower development genes (FULs, AP3, PI, and SEP2, etc.) were up-regulated. The floral integrators FT and SOC1 exhibited opposite expression dynamics: SOC1 was highly expressed during the early-to-mid stage, whereas FT peaked at the late stage, with the two showing opposing co-expression and correlation patterns. This suggests stage-specific divergence between the two integrators in coordinating flower bud differentiation and dormancy entry. Multiple hormone pathways (IAA, BR, JA, and SA, etc.) converged independently onto floral regulatory hubs through their biosynthesis/metabolism and signal transduction genes, with numerous transcription factors also involved. Conclusions: These findings provide a comprehensive view of bud transcriptome dynamics and propose a molecular regulatory framework integrating flowering signals, hormones, and transcriptional cascades, offering a theoretical foundation and gene resources for blueberry breeding.

Amino acid permeases (AAPs) facilitate the uptake and transmembrane transport of amino acids and play critical roles in regulating plant growth, development, and stress responses. However, the characteristics and functions of the AAP gene in pepper remain unclear. In this study, nine CaAAP genes were identified within the pepper (Capsicum annuum) genome and designated as CaAAP1-CaAAP9. Phylogenetic analysis revealed that CaAAP6, CaAAP7, and CaAAP9 belong to subfamily I, CaAAP8 is the sole member of subfamily III-E, and the remaining genes are classified within subfamily II. Collinearity analysis indicated the presence of both tandem and segmental duplication events among the nine CaAAP genes in pepper, as well as four and seven duplicated gene pairs between Arabidopsis and tomato, respectively. Expression profiling demonstrated that CaAAP genes exhibit pronounced tissue-specific expression patterns and differential expression in response to exogenous plant hormones and various abiotic stress treatments. Notably, drought stress elicited a significant up-regulation of CaAAP6 expression. Functional characterization confirmed that CaAAP6 localizes to the cell membrane. Silencing of CaAAP6 resulted in a significant reduction in plant drought tolerance, accompanied by disrupted tissue architecture, and stomatal closure. Furthermore, the concentrations of H₂O₂, O₂^•−, and MDA exhibited increases of 76.19%, 108.52%, and 20.23%, respectively. Concurrently, the activities of SOD, POD, and CAT decreased by 42.32%, 64.09%, and 109.64%, respectively. Additionally, the transcriptional levels of the CaRD22, CaRD29B, and CaDREB2A genes were reduced by 135.56%, 67.19%, and 37.91%, respectively, compared to the control plants. Collectively, these findings provide initial functional evidence that CaAAP6 contributes to drought tolerance in pepper.

‘Fengtang’ plum is increasingly cultivated in southern China under mountain cultivation conditions, which involve lower temperatures, higher irradiance, and thinner soils. These conditions may uniquely shape the rhizosphere microbiome and influence tree health, yet their effects remain poorly understood. This study aimed to characterize the structural and taxonomic characteristics of the rhizosphere microbial community of ‘Fengtang’ plum grown under mountain cultivation conditions, and to identify key microbial groups associated with plant growth. We performed 16S rRNA and ITS high-throughput sequencing on rhizosphere and non-rhizosphere soil samples from ‘Fengtang’ plum orchards. Significant differences in α-diversity and β-diversity were observed between rhizosphere and non-rhizosphere communities. Dominant bacterial phyla included Pseudomonadota, Actinobacteriota, Acidobacteriota, and Chloroflexi; Ascomycota and Basidiomycota dominated in fungal communities. Dominant microbial groups were consistent across phylum, class, and order levels. Beneficial genera such as Streptomyces, Bacillus, and Rhizobium were enriched in the rhizosphere, and are considered putative core functional genera based on their known plant-growth-promoting traits. The microbial community in the rhizosphere shows distinct compositional patterns that may be linked to microecological balance. This study seeks to provide a comprehensive perspective for understanding the microbial communities associated with the plum tree rhizosphere.

Background/Objectives: Floral bud morphogenesis is a critical developmental process determining yield potential in blueberry, yet the molecular regulatory mechanisms in leaves during this phase remain poorly understood. Methods: In this study, we employed a time-series transcriptomic approach to investigate leaf gene expression dynamics during floral bud morphogenesis in rabbiteye blueberry. Leaves were sampled at six time points spanning the critical developmental window from the cessation of summer shoot growth to bud swell and dormancy onset. Results: RNA-seq analysis generated 121.68 Gb of clean data, and weighted gene co-expression network analysis (WGCNA) identified four stage-specific modules (brown, red, blue, turquoise) significantly associated with distinct morphogenetic phases. The brown module (0–6W) was enriched in photosynthesis and hormone signaling pathways, while the red (9W) and blue (12W) modules featured protein processing, stress and hormone signaling, and carbohydrate metabolism. The turquoise module (15W) was dominated by carbon metabolism and flavonoid biosynthesis genes. Key flowering-related genes exhibited dynamic expression patterns: FT was specifically upregulated at the late stage (15W), AP2 genes peaked at mid-stage (9–12W), and COL9 showed early high expression (0–3W). Hormone-related gene analysis revealed extensive involvement of multiple pathways, with brassinosteroid (BR) signaling comprising the largest number of genes (101). Co-expression networks further identified hub genes, including FT, COL9, AP2, ERF1, SR160, LOX3-1, and transcription factor genes like MYB-related, as potential central regulators. Conclusions: Our findings demonstrate that blueberry leaves undergo a phased functional transition from a photosynthetic source to a hub for signal integration and metabolic support during floral bud morphogenesis, actively contributing to reproductive development through systemic signaling. This study provides novel insights into flowering regulation in woody perennials and establishes a foundation for marker-assisted breeding and cropping season management in blueberry.

This review offers a comprehensive analysis of the extensive research on methyl jasmonate (MeJA)-induced plant disease resistance. It aims to elucidate the signal transduction pathways, interactions with other phytohormones, regulation of related gene expression, and the fundamental mechanisms contributing to plant disease resistance. The review provides a detailed examination of MeJA-induced defense responses and the sustainability of the induced resistance. Furthermore, it assesses the practical applications and current status of MeJA across various plant species and explores potential research directions in disease management. It serves as a systematic reference for a deeper understanding of MeJA-induced plant disease resistance and holds significant importance for advancing further developments in the field.

Blueberries are among the richest fruit sources of anthocyanins, which contribute significantly to fruit quality, flavor, and plant physiology. Anthocyanins also exhibit various health-promoting effects, making them valuable in the food, pharmaceutical, and cosmetic industries. Although the structures of anthocyanins and the general framework of their biosynthesis have been largely elucidated, the precise regulatory mechanisms governing anthocyanin production in blueberries remain incompletely understood. Here, we analyze recent advances in understanding blueberry anthocyanin regulation at the enzymatic pathway level (CHS, CHI, F3H, DFR, ANS) and the genetic level (MYB, bHLH, WD40 transcription factors), with particular emphasis on the roles of environmental factors such as light and temperature. This review also explores the diverse health benefits of blueberry anthocyanins, including their antioxidant properties and potential role in preventing chronic diseases such as cardiovascular disorders, neurodegeneration, and cancer. Furthermore, we discuss practical applications of anthocyanins in food, cosmetics, textiles, and pharmaceuticals, as well as emerging uses in smart packaging. Importantly, we highlight how metabolic engineering, synthetic biology, and bioprocess engineering strategies can be leveraged to enhance anthocyanin biosynthesis, stability, and yield in blueberry-based systems. By integrating insights into biosynthetic mechanisms, health impacts, and practical applications, this review provides a comprehensive framework for future research to maximize the potential of blueberry anthocyanins.

With-No-Lysine (WNK) kinases constitute a subgroup within the serine/threonine protein kinase family, characterized by the absence of a catalytic lysine residue in the kinase subdomain II located in their N-terminal region. These kinases play critical roles in regulating plant growth, development, and responses to abiotic stressors. However, members of the WNK and their responses to heat stress in pepper (Capsicum annuum L.) remain unexplored. In the present study, we identified eleven WNK genes within the genome of pepper cultivar ‘UCD-10X-F1’ and designated them CaWNK1 to CaWNK11 according to their chromosomal positions. Comprehensive analyses were conducted to elucidate their phylogenetic relationships, chromosomal distribution, collinearity, gene structure, protein properties, and cis-acting elements within promoter regions. The findings revealed that the CaWNK gene family segregates into five distinct subgroups. Comparative genomic analysis identified eleven and nine segmental duplication gene pairs between pepper and tomato and between pepper and Arabidopsis, respectively. Within the pepper genome, two pairs of segmentally duplicated genes and two pairs of tandemly repeated genes were also detected. The CaWNK gene sequences in pepper exhibited a high degree of conservation; however, variations were observed in the number of introns and exons. Analysis of the promoter regions revealed an abundance of cis-acting elements associated with growth and development, stress responses, and hormone regulation. Subsequent transcriptomic analyses demonstrated that CaWNK genes displayed tissue-specific expression patterns and differential expression levels following treatments with exogenous plant hormones and abiotic stresses. Notably, the expression of CaWNK6 was significantly up-regulated under heat stress conditions. To elucidate the functional role of CaWNK6, virus-induced gene silencing (VIGS) was employed to suppress its expression in pepper seedlings. Silencing of CaWNK6 resulted in disrupted tissue architecture, stomatal closure, and diminished heat tolerance. These phenotypic changes correlated with excessive accumulation of reactive oxygen species (ROS), reduced activity of antioxidant enzymes, and down-regulation of heat shock factor (HSF) genes in the silenced plants. Collectively, these findings offer valuable insights into the functional roles of CaWNK genes and hold significant implications for the development of novel heat-tolerant pepper cultivars.