The study aimed to find non-toxic and pollution-free post-harvest prevention and treatment methods replacing chemical fungicides to enrich the resources of mango stalk rot antagonist bacteria. Botryodiplodia theobromae Pat. and Phomposis mangiferae Ahmad were used as the indicator fungi, and actinomycetes with antagonistic effects on stalk rot fungi were isolated and screened from the rhizosphere soil of mango trees by the plate dilution and dual culture method. The classification status, live prevention effects, and the antimicrobial mechanism were preliminary studied. Antagonists A2, B85 and D16 were selected, which had antimicrobial effects and good genetic stability against both Botryodiplodia theobromae Pat. and Phomposis mangiferae Ahmad, and had inhibitory effects on Colletotrichum gloeosporioides, Pestalotiopsis mangiferae, Alternaria alternate and Botrytis cinerea, with a wide antifungal spectrum. In the live test, on the 3^rd day after inoculation, there were no significant differences in the diameter of the fruit lesions treated with antagonist strains A2, B85 and D16 (8.58, 8.50, 7.83 mm) and the imimerine-treated group (6.33 mm), but significantly lower than that of the control group (20.58 mm). Strains A2 and B85 were identified as Streptomyces malaysiensis, and D16 was Streptomyces lydicus. Strains A2, B85 and D16 inhibited the occurrence of pedicle rot by producing active substances with antimicrobial effects, inhibiting spore germination of dipodol, nutritional competition, and improving the activity of fruit SOD, POD and CAT. Among the three antagonistic strains, the D16 could also produce volatile organic compounds with antimicrobial effects to inhibit the occurrence of pedicle rot fungi. The three strains had certain antagonistic effects on pedicle rot bacteria and could be further studied.

Tetragonia tetragonoides (Pall.) Kuntze is a seawater vegetable with strong tolerance to multiple abiotic stresses. Plant thaumatin-like proteins (TLPs) are involved in various biological and abiotic stress responses. In order to elucidate the possible roles of a T. tetragonoides thaumatin-like protein gene (TtTLP11) in abiotic stress resistance, we cloned this gene and performed transgenic over-expression assay in Arabidopsis thaliana, then the homozygotic transgenic lines were obtained and performed subsequent analysis for stresses tolerance. In this study, the seeds from transgenic plants over-expressing TtTLP11 and wild type Arabidopsis plants were challenged with high salinity, high osmotic stress, heat and mixed salt-alkali stresses, by detecting the seed germinating rates, seedling growth status, thereby assessing the stress resistance of these transgenic Arabidopsis plants. The purpose of this study was to clarify the abiotic stress resistance functions of the TtTLP11 and the possible molecular mechanisms. The results showed that under various abiotic stress conditions, the over-expression of TtTLP11 could alleviate the inhibition effects of seed germination and relieve the environmental damage to seedlings, thereby improving the abiotic stress tolerance of transgenic plants. It is speculated that TtTLP11 might alleviate dramatic changes in osmotic pressure in plants and maintain water homeostasis, and then affect the stress tolerance of plants. The results could provide a theoretical basis for further analysis of the molecular regulatory network of plant response to alleviate abiotic stress damage.

The AT-hook Motif Nuclear Localized (AHL) protein family is known for its pivotal roles in plant growth regulation, developmental patterning, and stress signal transduction. Although the gene family has been studied in various plant species, the genomic characteristics, evolutionary mechanism, and expression profiles of the AHL family in cassava (Manihot esculenta) remain unexplored. In this study, we comprehensively investigated the evolutionary features and biological response of the MeAHL gene family through genome-wide identification, phylogenetic analysis, structural characterization, and large-scale transcriptomes based on the cassava SC205 reference genome. We identified 41 putative members through genome-wide identification. Physicochemical property analysis showed that all 41 MeAHLs were hydrophilic proteins, and 40 of them were unstable proteins, with the number of amino acids generally ranging from 188 to 446 aa. Phylogenetic analysis indicated that the MeAHL family members could be divided into two clades, Clade A and Clade B. Two MeAHL gene clusters were located in the distal telomeric regions of chromosomes Chr01 and Chr02, respectively. Replication type analysis revealed that the evolution of MeAHLs was mainly driven by whole-genome duplication (WGD) and dispersed duplication (DSD), with the Ka/Ks values <1. Evolutionary mechanism analysis indicated that whole-genome duplication (WGD) primarily drove the MeAHL gene family expansion. Gene structure analysis showed that MeAHL genes were mainly composed of 1‒10 exons. Analysis of conserved domains and motifs showed that all MeAHLs had the PPC/DUF296 domain and AT-hook motif. Members of Clade A generally contained one Type-I AT-hook motif. Among members of Clade B, except for SC20508G13380 and SC20509G13950, which contained one Type-II AT-hook motif, most members contained two AT-hooks (Type-I and Type-II). Cis-acting element analysis via PlantCARE showed that the cis-acting elements related to light response were the most abundant in MeAHLs, such as Box 4, G-box, and they also contained elements responsive to hormones, biotic stresses, and abiotic stresses, such as ABRE, MBS, W-box, and TC-rich repeats. Tissue-specific expression profiling revealed distinct expression patterns between two clades of MeAHL across 11 different tissues. Stress transcriptome analysis demonstrated significant responses of specific MeAHLs to drought (ABA/PEG treatments), cassava bacterial blight (Xanthomonas axonopodis pv. manihotis), and mite infestation, showing clade-specific regulatory patterns. Protein-protein interaction (PPI) network prediction suggested some MeAHLs formed functional modules with bHLH, NAC, ARF, and NB-LRR proteins involved in plant development and stress responses. This study would provide the systematic characterization of AHL family evolution and functional diversification in cassava, offering theoretical foundations for molecular breeding applications.

It was aimed to understand the nutrient contents in soil and the characteristics of ecological stoichiometry in the main coffee producing areas of Yunnan Province, Baoshan, Pu'er, and Xishuangbanna. The nutrient content and ecological stoichiometry of both coffee soil and leaves were assessed, thereby enhancing our understanding of the interplay between crops and soil elements while also revealing the status of soil nutrient limitations. Among the regions studied, the C content in Baoshan soil was significantly lower than that of Xishuangbanna (P<0.05), and C/N ratio in Baoshan soil was notably lower than that of Xishuangbanna and Pu'er, while N/P ratio in Baoshan was significantly higher than that of Pu'er coffee. The C content of coffee leaves in Pu'er was more than that of both Baoshan and Xishuangbanna significantly. There were obvious differences in C content and C/N ratios among the leaves from the regions (P<0.01). Leaf N/P threshold analysis indicated that Pu'er coffee had an N/P ratio ranging between 14 and 16, suggesting growth constraints due to both N and P elements, while leaf N/P ratio exceeded 16 for Baoshan and Xishuangbanna coffees, indicating a restriction primarily by phosphorus. Correlation analyses revealed a highly significant positive correlation between C and N levels within coffee soils (P<0.01). Moreover, significant positive correlations were observed between leaf C with C/N ratio and C/P ratio (P<0.01), alongside a notable positive correlation between leaf carbon content and soil nitrogen levels (P<0.01). The results indicated that nitrogen and phosphorus were the limiting factors for Pu'er coffee cultivation and applying nitrogen and phosphorus in production is advisable. In contrast, phosphorus was the primary limiting factor for both Baoshan's and Xishuangbanna's coffees production, therefore, appropriate application of phosphorus should be recommended.

Chitinase plays a crucial role in plant stress resistance and growth development. To elucidate the effects of plant hormones and environmental stress on the expression of the mustard chitinase gene, this study investigated three plant hormones-salicylic acid (SA), 1-amino-cyclopropane-1-carboxylic acid (ACC), and methyl jasmonate (MeJA)—and the influence on the transcriptional regulation of the chitinase gene family in Brassica oleracea cv. BaiHua. Additionally, seedlings were subjected to two stress conditions: infection by Pectobacterium carotovorum subsp. Brasiliense and exposure to high temperature. The transcriptional levels of the Chinese kale chitinase gene family members were analyzed using the quantitative real-time polymerase chain reaction (qRT-PCR) method. Results demonstrated that among the 18 genes within the chitinase gene family of Chinese mustard, 16 exhibited significant induction under soft rot fungal infection, while 8 responded to high-temperature stress. Furthermore, all 18 genes showed responsiveness to plant hormone-induced expression. This study highlights the potential role of the chitinase gene in mediating responses to hormonal signals and environmental stress, thereby contributing to stress resistance and growth development in plants. The findings would provide valuable insights for future molecular breeding strategies targeting Chinese kale.

Coconut wood (Cocos nucifera L.), an economically significant tropical tree, exhibits variations in fiber morphology and chemical composition that directly influence its processing performance and comprehensive utilization potential. This study systematically investigated the spatial variability of fiber morphological indices (length, width, cell wall thickness, lumen diameter, aspect ratio, and cell wall-lumen ratio) and chemical components (holocellulose, cellulose, and lignin) across different trunk heights (bottom, middle, top) and radial positions (outer, middle, inner) in 40-year-old coconut trees from Hainan. The analyses were conducted using wood microscopy, image analysis software, and chemical assays. Fiber length (696.84–969.94 μm), cell wall thickness (9.78–18.36 μm), and cell wall-lumen ratio (1.13–5.82) decreased significantly from the bottom to the top, while lumen diameter (3.60–10.15 μm) increased. Fiber width (17.41–20.76 μm) and aspect ratio (40.39–48.79) showed minor variations but exhibited an overall downward trend with increasing height. Fiber length, cell wall thickness, and cell wall-lumen ratio decreased from the outer to inner regions, whereas lumen diameter increased. Chemical analysis indicated decreasing trends for holocellulose (59.14%–70.32%) and cellulose (41.03%–44.85%) content along both vertical and radial gradients, while lignin (21.40%–23.60%) initially decreased and then increased vertically, with higher inner-region content. The study identified superior fiber morphology (longer fibers, thicker cell walls, smaller lumen diameters) and higher holocellulose and cellulose content in the bottom and outer regions. Compared to bamboo, coconut fibers are thicker, with thicker cell walls and smaller lumens but lower aspect ratio, making them particularly suitable for medium-to-short fiber pulping processes. This research elucidates the spatial variation mechanisms of coconut wood fiber morphology and chemical composition, could providing a theoretical foundation for optimizing pulping, fiberboard manufacturing, and bioenergy applications, Such insights can enhance resource utilization efficiency and support sustainable development in tropical timber industries.

Sugarcane (Saccharum officinarum L.), a crucial sugar crop in China, faces yield and quality constraints due to soil nutrient limitations. Severe soil acidification and nutrient imbalances in the southwestern Yunnan sugarcane-growing areas hinder the sustainable development of the industry. This study aimed to clarify the driving effects of soil stoichiometric characteristics on sugarcane leaf nutrient uptake, identify critical thresholds for soil acidification and nutrient limitations, and provide theoretical and technical foundations for precision fertilization and soil improvement. Soil (0-30 cm depth) and leaf samples were systematically collected from 121 sugarcane fields across nine townships in Lianghe County, Yunnan Province using a grid-based sampling strategy. Soil parameters analyzed included pH, organic matter, total nitrogen, total phosphorus, total potassium, alkaline nitrogen, available phosphorus, available potassium, and DTPA-extractable micronutrients. Leaf nutrients (total nitrogen, total phosphorus, total potassium) were analyzed after H₂SO₄-H₂O₂ digestion. Structural equation modeling (SEM) was employed to construct multi-path networks linking soil fertility (organic matter, total N/P/K, available nutrients), micronutrients (Fe, Mn, Cu, Zn), and environmental factors (pH) to leaf nutrient dynamics. Model parameters were optimized via maximum likelihood estimation, with standardized path coefficients (β) and determination coefficients (R²) quantifying factor contributions. Soils exhibited pronounced acidification (mean pH=5.07), with 78.23% of samples ≤pH 5.5. Zinc deficiency (<1.5 mg/kg) occurred at 84.75% of sites, while TK (2.27%), available Fe (59.90 mg/kg), and available Cu (1.04 mg/kg) remained relatively high; Organic matter correlated strongly with TN (r=0.929^**), TP (r=0.614^**), AN (r=0.847^**), AP (r=0.642^**), and AK (r=0.399^**), indicating its central role in nutrient retention. Soil acidification (pH<5.5) reduced cation exchange capacity by 26.7% and negatively correlated with AN (r=–0.290^**). Neutral to slightly acidic conditions (pH 6.0–6.5) enhanced phosphorus and potassium availability. Soil available nutrients emerged as pivotal drivers of leaf nutrient assimilation. This study systematically illustrated the multi-path regulatory mechanisms of soil stoichiometric traits driving sugarcane leaf nutrient uptake in southwestern Yunnan's sugarcane belt, quantitatively linking acidification with nutrient dysregulation. It is proposed that an integrated fertilization strategy—“ameliorate acidity-supplement zinc-regulate nitrogen-enhance carbon” should serve as the technical paradigm for high-yield sugarcane cultivation and sustainable soil management, which also could be universally referred by the agricultural ecosystems in tropical and subtropical acidic soils.

Leguminous green manure cover cropping and incorporation play a crucial role in improving soil conditions and enhancing nutrient cycling in ecosystems. Studying the decomposition characteristics and nutrient release patterns of green manure is of significant importance for the sustainable production of rubber plantations. This study selected four representative tropical leguminous green manures: Pueraria phaseoloides Benth (GT), Crotalavia anagroides H.B.K (ZSD), Tephrosia candida DC. (SMD), and Stylosanthes guianensis (Aubl.) Sw. (ZHC). During the vigorous growth period of the green manures, a 260-day field in-situ decomposition experiment was conducted using the nylon mesh bag method to explore the decomposition characteristics and nutrient release patterns of the leguminous green manures from different genera. The dry matter decomposition characteristics followed the “Olson” exponential model. The decomposition constants (k) ranked as follows, GT (3.01)>SMD (2.51) and ZHC (2.36)>ZSD (2.01), with GT being significantly higher than ZSD (P<0.05). At the end of the experiment, the dry matter remaining rate of the four green manures was ZSD (24.7%)>SMD (22.7%)>ZHC (21.7%)>GT (17.3%). The time required for 95% decomposition was 17.9, 15.3, 14.3, and 11.9 months, respectively. For carbon (C), nitrogen (N), phosphorus (P), and potassium (K), the remaining rate across the four green manures (GT, ZSD, SMD, ZHC) was N (15.5%–34.0%)>P (11.9%–30.4%)>C (15.1%–22.2%)>K (0.58%–1.07%). Calcium (Ca) and magnesium (Mg) residue ratea was Ca (45.0%–64.0%)>Mg (11.5%–31.9%). Iron (Fe), copper (Cu), and zinc (Zn) showed average residue rate of 160.9%, 138.3%, and 110.6%, respectively, indicating enrichment effects, while manganese (Mn) had an average residue rate of 36.3%. Notably, GT exhibited complete nutrient release for all elements, with the lowest remaining rate among the four green manures. In contrast, ZSD, SMD, and ZHC demonstrated enrichment effects for Fe, Cu, and Zn. In conclusion, the differences in decomposition and nutrient release characteristics among green manures would provide critical theoretical support for nutrient cycling and soil fertility improvement in rubber plantations, and technical guidance for sustainable rubber plantation management.

Cucumber mosaic virus (CMV) is a virus that can infect various monocotyledonous and dicotyledonous plants. Two efficient detection methods for CMV in orchids, real-time quantitative PCR (RT-qPCR) and reverse transcription loop-mediated isothermal amplification (RT-LAMP) were developed in the study. For RT-qPCR, a TaqMan probe-based assay was designed using conserved regions of the coat protein (cp) gene, with a cloned cp plasmid serving as the standard for calibration curve construction. For RT-LAMP, specific inner and outer primers were designed based on the cp gene conserved sequences too. Both methods specificity detection were performed using virus RNA from CMV, Cymbidium mosaic virus (CymMV), and Odontoglossum ringspot virus (ORSV) as templates, and for sensitivity detection was performed using 10-fold serial dilutions of CMV RNA as a template. Additionally, field-collected orchid samples were screened for CMV infection using both techniques. The CMV RT-qPCR and RT-LAMP detection methods established in this study detected only CMV-positive samples without cross-reactivity with CymMV or ORSV. The sensitivity of RT qPCR and RT LAMP was consistent with a dilution of 10⁶ times the original solution. The positive rate of CMV in field orchid samples was 26.7%. The results demonstrate that the RT-qPCR and RT-LAMP established in this study have strong specificity and high sensitivity, and are suitable for monitoring CMV infection in orchids in actual production processes.

The study established an ultra-performance liquid chromatography-tandem mass spectrometry technique for the simultaneous determination of six methoxyacrylate fungicides to clarify the possible cumulative dietary intake risk of methoxyacrylate fungicides in fresh mango. The Monte Carlo simulation and relative potency factor methods were employed to assess the cumulative risk of acute and chronic exposure to strobilurin intake from mango consumption in the targeted populations. In 126 mango samples from Hainan, Guangxi and Yunnan, 3 of 6 methoxyacrylate fungicide were detected. The detection rate of pyraclostrobin, azoxystrobinthe and kresoxim-methyl was 31%, 37% and 14% respectively. Picoxystrobin, trifloxystrobin and fluoxastrobin in mango samples were not detected. The ratio of methoxyacrylate fungicide found in a mango sample was 22%. The ratio of 2 and 3 kinds methoxyacrylate fungicides found in a mango sample was 22% and 5%. The most common co-occurrence of methoxyacrylate fungicides was pyraclostrobin and azoxystrobin. The results of dietary risk assessment showed that the risk of residual methoxyacrylate fungicides in mango ranged between 0.1% and 10.2% for acute dietary exposure and between 0.1% and 1.2% for chronic dietary exposure. The exposure was far below the thresholds of dietary risk. The study showed that the cumulative chronic and acute dietary exposure risk of methoxyacrylate fungicide residues in mango are within an acceptable range and do not pose an unacceptable risk to the health of the targeted population.