Chongjian Ma

Background: Ilex asprella is a traditional Chinese medicinal herb of considerable economic value. However, it has a strong tendency to accumulate cadmium (Cd), resulting in potentially excessive heavy metal levels that severely compromise its medicinal quality and industrial development. The physiological and molecular mechanisms underlying Cd tolerance and accumulation in I. asprella remain unclear. Organic acids play crucial roles in plant responses to heavy metal stress. Therefore, this study aimed to elucidate the molecular mechanisms of Cd tolerance in I. asprella roots by integrating transcriptomic and organic acid profiling analyses. Results: Under hydroponic treatment with 50 μmol/L CdCl₂ for different durations (0–72h), the total Cd content in I. asprella roots increased continuously and plateaued after 48h. Based on Mfuzz time-series clustering and lagged cross-correlation analysis, 6 Cd-responsive organic acids were identified: citric acid, malic acid, lactic acid, oxalic acid, acetic acid, and sinapic acid. These acids exhibited persistently increasing patterns in both roots and root exudates and were strongly positively correlated with root Cd content. Transcriptomic analysis revealed three major gene expression patterns, and weighted gene co-expression network analysis (WGCNA) identified core regulatory modules significantly associated with the six organic acids. Functional enrichment analysis showed that hub genes in these modules were mainly involved in pathways such as carbon metabolism, phenylpropanoid biosynthesis, and glyoxylate and dicarboxylate metabolism. Co-expression network construction further identified 15 key transcription factors (e.g., LBD31, WOX13, and MYB36) that may coordinately regulate organic acid biosynthesis and transport. Conclusions: These processes may contribute to Cd tolerance and accumulation in I. asprella. Cd stress activates specific transcription factors, upregulating functional genes involved in carbon metabolism, glycolysis, phenylpropanoid biosynthesis, and related pathways, thereby promoting the synthesis of organic acids such as citrate and malate. These organic acids contribute to Cd detoxification through multiple synergistic mechanisms, including Cd chelation, vacuolar sequestration, reactive oxygen species scavenging, and rhizosphere chelation. Ultimately, this enhances Cd tolerance and accumulation in This study proposes a model of Cd tolerance and accumulation mediated by organic acid metabolism in I. asprella: I. asprella . These findings provide genetic resources and a theoretical foundation for further understanding plant metal detoxification and for breeding varieties with reduced Cd accumulation.

Medicinal baths are an important component of traditional Chinese medicine and are widely used for postpartum recovery, neonatal care, and general health maintenance. Although medicinal bathing practices among ethnic groups such as the Yao and Tibetan have been relatively well documented, ethnobotanical research on Hakka medicinal baths in Guangdong remains limited, despite their widespread use among postpartum women and newborns. Field investigations were conducted in 19 Hakka settlements in northern Guangdong from 2023 to 2024. Data were collected through semi-structured interviews, individual consultations, and field observations involving 138 Hakka informants. Fidelity Level (FL) and Informant Consensus Factor (FIC) were used to evaluate the cultural importance of medicinal bath plants and the degree of agreement among informants. A total of 108 medicinal bath plant species were documented, most of which were herbaceous. The most frequently used plant parts were the whole plant, leaves, and stems. Knowledge of medicinal bath practices was mainly concentrated among older women, who play a central role in postpartum and neonatal care. These plants were reported to be used for the prevention and management of more than 30 health conditions. FIC values ranged from 0.61 to 0.87, with the highest agreement observed for postpartum recovery, respiratory diseases, and skin diseases. Ten plant species had a Fidelity Level (FL) of 100%, indicating high cultural recognition and importance. Compared with the medicinal bath practices of neighboring Yao communities, Hakka practices are characterized by milder remedies, simpler formulations, and a stronger emphasis on family-based healthcare, particularly for mothers and infants. Hakka medicinal baths reflect intergenerational knowledge transmission, practical healthcare strategies, and culturally embedded healing practices. This study systematically documents the medicinal bath plants used by the Hakka in Guangdong and provides a basis for the conservation of traditional knowledge and the sustainable use of medicinal plant resources. The findings also highlight the relevance of Hakka medicinal bath practices in postpartum care, infant healthcare, and community-based complementary healthcare.

B-cell lymphoma 2 (Bcl-2)-associated athanogene (BAG) family proteins are co-chaperones that regulate growth, development, and cell death and are evolutionarily conserved across eukaryotes. The BAG gene family has attracted intense interest in human health research, but its plant counterparts have received little attention. In this study, we conducted a genome-wide scan of the BAG family in passion fruit, a crop of great economic importance. Fifteen PeBAG genes were identified, with all but PeBAG5 having multiple copies. PeBAG members, each characterized by a BAG domain, were categorized into two groups: Group 1 (PeBAG1/2/3/4) with extra ubiquitin domains, and Group 2 (PeBAG5/6-1/6-2) with additional plant-specific calmodulin-binding domains. The transcriptome data suggest that PeBAGs exhibit high gene expression in stems, flowers, and fruit, while PeBAG4-3 and 6-1 upregulated under hormonal and abiotic stresses. qRT-PCR further confirmed the heat stress activation of PeBAG4-3 and 6-1. Subcellular localization in planta revealed varied compartmentalization, with members in the nucleus, cytoplasm, and plastids demonstrating functional divergence. This study provides a guide for investigating and employing PeBAG genes to improve heat resistance in passion fruit.

Sucrose phosphate synthase (SPS) is a rate-limiting enzyme in plant sucrose biosynthesis. However, the SPS gene family in luffa remains unidentified, and its functional involvement in sugar metabolism is unexplored. Here, we present the first genome-wide identification and functional analysis of the LaSPSs in luffa. We identified nine LaSPS genes, characterized their physicochemical and evolutionary properties, and analyzed their expression patterns in different tissues and response to ethylene and drought treatments. Nine tandem-duplicated LaSPS genes formed four clusters (T1(1/2), T2(3/4), T3(5/6), T4(7–9)) with conserved architectures. RNA-seq analysis indicated a ubiquitous downregulation of LaSPS genes in senescing luffa, wherein sucrose content correlated significantly with all LaSPS members except LaSPS1/2. Exogenous ethylene substantially repressed LaSPSs transcription, while 1-methylcyclopropene (1-MCP) treatment showed induction. Notably, LaSPS3/4 displayed high activation under drought stress. Functional validation via heterologous expression in tobacco confirmed that LaSPS3/4 positively regulates drought resistance. In summary, this study provides a novel perspective for the in-depth investigation of the molecular evolutionary mechanism of the LaSPS gene family and its biological functions in luffa.

Luffa (Luffa acutangula) serves as an important edible, medicinal, and industrial crop. Sucrose synthase (SUS, EC 2.4.1.13) catalyzes sucrose metabolism and facilitates the entry of photosynthetically derived sucrose into metabolic pathways, playing crucial roles in plant growth, development, and stress responses. However, systematic investigations on the SUS gene family in luffa remain relatively scarce. In this study, we identified nine LaSUS family members distributed unevenly across six chromosomes. Their physicochemical properties and evolutionary relationships were systematically elucidated using bioinformatics tools. RNA-seq analysis revealed distinct expression patterns of LaSUS genes during luffa fruit aging, with most genes showing significant down-regulation during this process. Notably, several genes exhibited significant correlations with sucrose content during fruit aging. RT-qPCR analysis demonstrated the drought stress responsiveness of LaSUS genes, with LaSUS1 showing marked up-regulation under drought conditions. Furthermore, overexpression experiments in tobacco confirmed that LaSUS1 contributed to sugar accumulation, increased antioxidant enzyme activities, and positively regulated drought tolerance in luffa. This comprehensive study not only characterizes the LaSUS gene family and bridges the research gap of SUS genes in luffa but also provides theoretical support for investigating the roles of SUS genes in fruit ripening and abiotic stress responses in luffa.

Arsenic (As) exposure through agricultural soil contamination poses significant health risks and threatens food security. This study explored the efficacy of hyperaccumulator plant diversity and intercropping systems in enhancing As removal from contaminated soil while simultaneously reducing As uptake in peanuts (Arachis hypogaea L.). Thus, a pot experiment was conducted using As-contaminated soil, peanut plants, and hyperaccumulator species as the experimental materials. The experimental treatments included monocultured peanuts (Ck) and peanuts intercropped with Pteris cretica. (P*Pc), intercropped peanut with Spinacia oleracea L. (P*So), and intercropped peanut with P. cretica and S. oleracea L. (P*Pc*So). Our findings revealed that the intercropping system significantly reduced soil As levels compared to monocropping. In addition, peanut As uptake was significantly decreased in hyperaccumulator plants, with enhanced effects under hyperaccumulator plant diversity, minimizing the risk of As transfer to the food chain. Moreover, the As removal rate was higher under intercropping than under monocropping, with the highest removal rate of 88% under intercropped peanut/P. cretica/S. oleracea L., followed by peanut/S. oleracea L. (81%) and peanut/P. cretica (80%). The results demonstrate the potential of using diverse hyperaccumulator plants and intercropping systems as sustainable and effective methods for remediating As-contaminated soils, while simultaneously ensuring food safety. However, further research is needed to elucidate the underlying mechanisms driving these effects and to optimize the phytoremediation of As-contaminated soil and crop production.