Natural rubber is an important industrial raw material and strategic resource. It has excellent properties such as comparable elasticity, flexibility and resistance to high temperature, which cannot be replaced by synthetic rubber. The rubber tree (Hevea brasiliensis) is still the only commercial source of natural rubber. Previous studies have reported the key genes involved in rubber biosynthesis including HbSRPP, HbHRT and HbFDP play crucial roles in increasing rubber yield, while MYB, as a transcription factor, may participate in the synthesis of natural rubber. In the study, a MYB transcription factor HblMYB16 gene was cloned from rubber tree, and bioinformatics and expression analysis were carried out successfully. The results showed that the open reading frame (ORF) of HblMYB16 was 1116 bp, encoding 371 amino acids, and the total average hydrophilicity was -0.498, which was a hydrophilic protein containing the R2R3-MYB domain and belonging to the MYB transcription factor family. HblMYB16 was highest expressed in latex and localized in the nucleus. It was found that jasmonic acid had a promoting effect on the expression of HblMYB16, HbSRPP, HbHRT and HbFDP, while ethylene only had an impact on the expression of HblMYB16 and HbFDP. At the same time, the interactions between HblMYB16 and the rubber biosynthesis key genes HbSRPP, HbHRT and HbFDP were verified by yeast one hybrid. The studies would lay a foundation for further revealing the molecular mechanism of HblMYB16 participating in natural rubber biosynthesis.

Pineapple (Ananas comosus) ranks as the world's third most important tropical fruit and is a significant economic crop in China's tropical regions. To investigate the role of the dihydroflavonol 4-reductase (DFR) gene family in anthocyanin accumulation in pineapple and provide a theoretical foundation for germplasm improvement, this study identified and preliminary functionally analyzed members of the pineapple DFR gene family. A total of 17 dihydroflavonol 4-reductase genes were identified in the whole genome of pineapple, which were named AcDFR1 to AcDFR17 and distributed unevenly on 10 chromosomes. AcDFRs encoded proteins ranging from 313 to 378 amino acids (aa) in length, with molecular weights between 34.73 and 47.74 kDa and isoelectric points (pI) from 5.10 to 8.9. The secondary structure of AcDFR proteins primarily consisted of α-helices and β-sheets, with α-helix content ranging from 38.73% to 43.07% and β-sheet content from 13.24% to 15.64%. Phylogenetic analysis revealed that the 17 AcDFRs formed four subfamilies. The motif arrangement and number of exons were similar among AcDFRs. The AcDFR genes promoter regions contained multiple cis-acting elements responsive to light, hormones, abiotic stress, growth and development. Real-time quantitative PCR analysis revealed significant expression variations of AcDFRs genes across different pineapple tissues (roots, stems, leaves, flowers, pulp, peel), though most genes exhibited high expression in both pulp and peel. Cloning and identification of AcDFRs revealed sequences largely consistent with predicted sequences. Subcellular localization studies of the AcDFR1 in tobacco leaves via transient expression indicated localization to the cytoplasm and cell membrane. The findings would provide theoretical references for further investigation into the functions of the dihydroflavonol-4-reductase gene family in pineapple and for pineapple quality improvement.

S-adenosylmethionine synthase (SAMS) is a key enzyme catalyzing the synthesis of S-adenosylmethionine (SAM, S-adenosylmethionine), widely involved in various biological processes in plants, such as epigenetic regulation, oxidative stress, and growth and development. In this study, the full-length cDNA sequence of CaSAMS3 was successfully cloned from coffee, and the physicochemical properties, protein structure, conserved domains, and evolutionary characteristics of the encoded CaSAMS3 protein were analyzed. Through cis-acting element analysis and protein interaction network prediction, and the metabolic processes involving CaSAMS3 were explored, and its expression pattern was analyzed in combination with qPCR and subcellular localization studies. The results showed that the open reading frame length of CaSAMS3 was 1173 bp, encoding a hydrophilic protein (molecular weight 42.57 kDa, theoretical isoelectric point 6.07), with a secondary structure mainly composed of α- helices and irregular curls, and located on cell membrane and nucleus. The protein contained a typical SAMS conserved domain and had the highest homology with SAMS in kiwifruit. Its promoter contained response elements related to light, hormones, stress, and growth and development, including MYB and MYC binding sites. CaSAMS3 exhibited tissue-specific expression, and its expression trend during developmental stages was consistent with accumulation pattern of caffeine. This study would provide an important theoretical basis for elucidating the biological function of CaSAMS3 in the regulation of caffeine synthesis, and provides a potential target for improving coffee quality and resistance.

This study represents sequencing of the chloroplast genome of the tea plant variety Zhuyeqi, with a focus on analyzing its structural characteristics, codon usage bias, and phylogenetic relationships. The results revealed that its chloroplast genome had 157 072 bp, with 135 functional genes annotated. The GC content in the IR region was found to be the highest (42.96%), and several intron-containing genes, such as clpP and ycf3, were identified. Codon usage bias analysis indicated a relatively weak bias, primarily driven by natural selection (contribution rate of 86.6%). Optimal codons were mostly A/U-ending, deviating from expectations based on mutational pressure. Phylogenetic analysis further confirmed that Zhuyeqi formed a highly supported monophyletic clade with cultivated types such as Pu-erh tea and Baihao tea, demonstrating close maternal genetic relationships. This study would provide important insights into the evolution of Theaceae species and the functional optimization of chloroplast genomes.

Plant annexin is a conserved calcium-dependent phospholipid binding protein involved in plant growth, development and stress resistance. The sequence characteristics and expression patterns of the ANX gene family in C. oleifera remain unclear. For this reason, the present study aims to investigate the expression regulatory mechanisms of this gene family in the stress resistance responses of C. oleifera. Three ANX genes were identified from the whole genome of C. oleifera, and the physical and chemical characteristics, evolutionary relationship, gene structure, conserved sequence, chromosome location, expression level in different tissues and the content of annexin under drought stress were analyzed in the study. Phylogenetic analysis showed that 15 different families were clustered into 5 groups, among which CsANX and CoANX1/2 from Camellia were clustered into a large branch with similar motif patterns. Many cis-elements involved in light response and plant hormone response were identified in the promoter region of CoANX. Chromosome localization showed that the three CoANX genes were distributed on three chromosomes (A_chr 09/13/14) of C. oleifera. The expression pattern analysis showed that CoANX showed tissue-specific patterns in different growth stages and tissues. In addition, stress analysis showed that CoANX3 showed a high expression trend under drought conditions, while the expression of CoANX3 in the treatment group sprayed with brassinolide decreased. Under phosphorus and aluminum stress, the expression of ANX in C. oleifera increased significantly. The above results indicate that CoANX may play a key role in the stress resistance of C. oleifera. This study would lay a foundation for elucidating the molecular mechanism of ANXs in regulating the biological processes of plant growth and development.

The aim of the study was to characterize the chloroplast genome structure and phylogenetic relationships within the genus Bulbophyllum. We sequenced, assembled, and annotated the chloroplast genomes of B. rothschildianum and B. longissimum for the first time. Comparative analyses of codon usage bias, repeat sequences, and sequence variation were then conducted with the available chloroplast genomes from four previously published Bulbophyllum species. The chloroplast genome of B. rothschildianum and B. longissimum was 148 447 bp and 151 095 bp, respectively, both showing a typical circular quadripartite structure containing 126 and 129 functional genes. Codons encoding leucine exhibited the strongest usage bias, with codons ending in A/U being particularly abundant. SSR analysis revealed mononucleotide repeats (predominantly A/T type) were most abundant, and palindromic repeats dominated among long repeats. Highly variable regions were mainly located in non-coding regions and selected coding genes (e.g., matK and ycf1), with evident expansion and contraction at IR/SC boundaries. Phylogenetic analysis showed that the 32 Bulbophyllum species formed a strongly supported clade and exhibited clear geographic differentiation into Asian and Central and South American lineages, with B. rothschildianum and B. longissimum clustering together within the Asian lineage and being closely related. The study would provide molecular insights into resource development, genetic conservation, and systematic research in the genus Bulbophyllum.

Ocimum gratissimum is widely utilized due to its significant medicinal and culinary value. However, substantial variations in volatile components and medicinal metabolite content exist among different germplasms, influenced by geographical origin, cultivation conditions, and environmental factors. The variations directly impact the stability of pharmacological efficacy and industrial-scale production. To address this, the present study employed an integrated metabolomics and transcriptomics approach to systematically investigate the aroma profiles, metabolite composition, and regulatory mechanisms of two distinct O. gratissimum germplasms (G096 and G134). Sensory evaluation confirmed that both accessions exhibited a characteristic clove-like aroma. Metabolomic analysis identified 1094 volatile metabolites, with 784 showing significant differential accumulation between the two germplasms. Correlation analysis between differential metabolites and sensory attributes revealed that eugenol was the key metabolite responsible for the distinctive flavor of O. gratissimum. Transcriptomic profiling identified 54 936 differentially expressed genes (DEGs), including 27 220 upregulated and 27 716 downregulated genes. Through metabolic pathway prediction, a biosynthetic pathway for eugenol in O. gratissimum was constructed, identifying PAL, C4H, 4CL, HCT and C3'H as critical regulatory genes governing eugenol biosynthesis. This study would not only elucidate the biosynthetic mechanism of the primary flavor compounds in O. gratissimum, but also provide a crucial molecular theoretical foundation for quality improvement and standardized production. The findings would hold significant scientific and practical value for advancing the industrial development of O. gratissimum.

Flg22 is an artificially synthesized 22-amino-acid peptide derived from the conserved N-terminal region of bacterial flagellin, playing a crucial role in regulating plant immune responses. Due to the high cost of artificially synthesized flg22 short peptides and limitations for large-scale application, this study aimed to determine the suitable conditions for prokaryotic induction expression of the flg22 protein and to verify its function, thereby determining whether it could replace the commercially used flg22 short peptides. In this study, the pET32a-flg22 prokaryotic expression vector was synthesized, and we then compared protein expression efficiency under induction at 28 ℃ and 37 ℃. Additionally, we detected the dynamic burst of reactive oxygen species (ROS) in cassava treated with flg22 peptides and flg22 proteins at different concentrations to validate the functions. The results indicated that 28 ℃ was the optimal induction temperature for inducing flg22 protein expression. ROS measurements showed that within a specific concentration range, the peak intensity of ROS increased with the increase in flg22 protein concentration. Furthermore, after spraying cassava leaves with 60 μg/mL and 600 μg/mL of flg22 recombinant proteins, as well as 2.27 μg/mL of flg22 peptides, for three days, we inoculated plants with the pathogen Xam (Xanthomonas axonopodis pv. manihotis, Xam). Compared to treatment with sterile water, both flg22 protein and flg22 peptide treatments showed significant antibacterial effects against Xam in cassava plants, with the 60 μg/mL and 600 μg/mL flg22 protein treatments showing notably stronger antibacterial activity than the flg22 peptide. The results preliminarily identified the prokaryotic expression conditions of flg22 recombinant protein and verified that its function in inducing plant defense responses is consistent with that of the peptide, providing a theoretical basis for substituting commercial peptides with flg22 recombinant protein.

High yield with cold resistance clones is the core objective of rubber tree breeding in Yunnan. In this study, the cold-resistant clone GT1, which exhibits strong tolerance to radiative chilling injury, was selected as the female parent, and the widely cultivated fast-growing, high-yielding variety Yunyan 277-5 was used as the male parent. Through artificial isolated pollination, hybrid offspring were obtained. After a sexual family trial, individual plants with potentials were selected from the progeny population and entered into small-scale and large-scale clone comparative trials. This process led to the selection of an excellent clone, Yunyan 76-235, which is characterized by high yield and fast growth with the cold resistance and latex production type comparable to the clone RRIM600. Thirty years of systematic evaluation demonstrated that Yunyan 76-235 exhibits rapid early growth, with an average annual girth increment of 6.0 cm by the 6^th year after planting in the primary trial area, which is 115.4% of the clone RRIM600. It also shows high yield of dry rubber, with an average annual dry rubber yield per tree of 2.64 kg in years 1-5 of tapping in the small-scale clone comparative trials, representing 149.26% and 168.54% of the RRIM600 and GT1, respectively. In the large-scale clone comparative trials, the average annual rubber production per tree in years 1-13 of tapping was 4.6 kg, which is 140.12% of the RRIM600. Its cold resistance is stronger than that of RRIM600 but weaker than that of GT1 and Yunyan 77-4. The successful breeding of clone Yunyan 76-235 enriches the genetic resources for rubber cultivation in areas of Yunnan where prone to mild and moderate cold damage, providing variety support for the development and enhancement of the local rubber industry.

To establish a regeneration system for somatic embryo-derived plants from the anthers of the triploid rubber tree clone Yunyan 73-46, this study utilized anthers as explants and employed an orthogonal experimental design to examine the effects of various hormone combinations on callus and somatic embryo induction efficiency. Furthermore, the morphological characteristics and differentiation capacity of callus under different culture duration were analyzed. Hormones were crucial for callus induction. In the absence of hormones, anthers failed to dedifferentiate and underwent browning and necrosis after 10d. In media containing 2,4-D, NAA, KT and TDZ, anther dedifferentiation to produce callus occurred with induction rates ranging from 15% to 91.56%, with a mean of (69.41±30.37)%. The impact of 2,4-D, NAA, KT and TDZ on callus induction rate and subsequent somatic embryogenesis rate were all highly significant (P<0.01), with the order of influence being 2,4-D>TDZ>NAA>KT. The optimal combination identified through comprehensive screening was 2,4-D 1.0 mg/L+NAA 0.8 mg/L+TDZ 0.02 mg/L. Upon verification, the callus induction rate and subsequent somatic embryogenesis rate was (86.15±1.53)% and (14.46±0.89)%, respectively, marking significant improvements of 2.31% and 5.40% over the best experimental combination (G7). The somatic embryogenesis capacity of this clone was generally low, with somatic embryo formation rates ranging from 6.91% to 19.31%, with a mean of (10.58±3.95)%. The effects of 6-BA, ABA, NAA and KT on somatic embryogenesis rate were highly significant (P<0.01), with the order of influence being ABA>6-BA>NAA>KT. The optimal combination was 6-BA 0.4 mg/L+ABA 0.2 mg/L+NAA 0.2 mg/L+KT 0.2 mg/L (M9), achieving a somatic embryogenesis rate of (19.31±0.60)%, which was significantly higher than other treatments. The optimal culture duration for callus was determined to be 55 d, which exhibited superior growth status without browning and the strongest somatic embryo differentiation capacity. The somatic embryogenesis rate was (30.83±1.67)%, the cotyledonary embryo formation rate was (18.33±0.83)%, and the average number of somatic embryos was (0.63±0.03), all of which were extremely significantly higher than those at other culture durations. By optimizing the hormone ratios during callus induction and somatic embryogenesis stages of Yunyan 73-46 anthers, coupled with adjusting the duration of callus induction culture, the production efficiency of anther-derived somatic embryo plantlets can be significantly enhanced. This approach would provide technical support for establishing a large-scale propagation system of somatic embryo plantlets for triploid rubber tree clones.

Date palm (Phoenix dactylifera) is a key economic crop in arid and semi-arid regions, which possesses ecological functions of sand fixation and water conservation, economic value driven by deep processing, as well as profound religious and cultural significance. This paper reviews the research progress in its genetic breeding from the following aspects. In germplasm resources, core germplasm banks have been established by institutions such as King Faisal University of Saudi Arabia, the National Plant Gene Bank of Iran, and the Chinese Academy of Tropical Agricultural Sciences. The institutions preserve germplasm resources by combining technologies like smart irrigation and cryopreservation, while molecular marker technologies including SSR and SNP have been applied to reveal genetic differences among date palm varieties. In breeding methods, traditional selection and hybrid breeding have laid the foundation for date palm breeding. Modern biotechnologies such as high-throughput sequencing, somatic embryogenesis, and CRISPR/Cas9 have accelerated the process of precision breeding. The current core challenges in date palm breeding include difficulty in early sex identification due to dioecy, a complete growth cycle exceeding 10 years, highly heterozygous genome, and lagging molecular research. Future breeding efforts should focus on developing varieties resistant to abiotic stresses such as hot temperature, drought and salinity-alkalinity, preventing and controlling pests and diseases including red palm weevil, Fusarium spp., and leaf spot disease, and optimizing fruit yield and quality. Meanwhile, it is necessary to deepen research on genetic mechanisms, break through bottlenecks in gene editing technology, and strengthen international exchange and cooperation of germplasm resources, to promote the sustainable development of the global date palm industry.

Determining the appropriate nitrogen application rate for Ficus hirta Vahl. is one of the key cultivation techniques for establishing an efficient and ecological "rubber-Ficus hirta Vahl." agroforestry system. This study evaluated five nitrogen application treatments, 0, 150, 225, 300 and 375 kg/hm² (denoted as CK, N₁₅₀, N₂₂₅, N₃₀₀ and N₃₇₅), and conducted a comprehensive analysis of the suitable nitrogen rate from the perspectives of productivity, resource use efficiency, and ecological footprint. The results showed that, compared with the CK treatment, nitrogen application significantly increased the yield, biomass, and economic benefits. Among the treatments, N₂₂₅ and N₃₀₀ performed the best, achieving a yield of 15 438 and 15 150 kg/hm² and an economic benefit of 60 950 and 57 555 yuan/hm², respectively (P<0.05). Compared with CK, nitrogen application significantly improved solar utilization efficiency by 59.1%-76.9%, but significantly reduced carbon efficiency by 46.2%-73.7%. The partial factor productivity from applied nitrogen also decreased significantly with increasing nitrogen application (P<0.05). N₁₅₀ exhibited the best overall performance in resource use efficiency, followed by N₂₂₅. Similarly, N₁₅₀ showed the best overall performance in terms of carbon and nitrogen footprints, followed by N₂₂₅. Nitrogen uptake in Ficus hirta Vahl. across different treatments ranged from 117.8 to 174.0 kg/hm², with the CK and N₁₅₀ showing higher nitrogen uptake than nitrogen input. Taking into account the productivity, resource use efficiency, ecological footprint and sustainability of nitrogen supply, this study concludes that N₂₂₅ is the suitable nitrogen application rate for establishing an efficient and ecological "rubber-Ficus hirta Vahl." agroforestry system.

To identify periods of oxygen deficiency in the root zone of pineapples, understand the mechanisms of oxygen changes, and provide sufficient response time for oxygen-enriching irrigation technology management and soil regulation to address abnormal fluctuations in oxygen content in the root zone, this study utilized a soil oxygen diffusion-consumption coupling mechanism constructed based on the Monte Carlo method. In model construction, the study fully considered soil oxygen diffusion, root respiration, and microbial oxygen consumption processes. Using parameter perturbation and uncertainty sampling, the model incorporated measured boundary conditions and depth-stratified initial concentration settings. Combined with multi-layer soil profile monitoring data, the model established a simulation system for oxygen content changes at depths of 10-40 cm in three typical soil types (loam, sandy soil, and clay). Finally, the model was validated using field trial data from spring 2025. The results showed that the model demonstrated strong predictive capability under various soil and depth conditions (R²>0.95, with the lowest RMSE of 0.214 mol/m³). The error distribution fluctuated slightly with increasing depth but remained within an acceptable range overall. Further analysis revealed that the model successfully identified periods prone to oxygen deficiency within 3-12 hours after irrigation or rainfall events. In oxygen deficiency identification, the model achieved over 90% accuracy in determining responses below the critical concentration (1.5 mol/m³). The above results validate the effectiveness of the constructed model in simulating root zone oxygen dynamics and providing risk warnings, aiming to provide a theoretical basis and predictive foundation for intelligent oxygen management in pineapple fields.

The study was aimed to solve the problems of relatively extensive cultivation and low soil quality of Pandanus amaryllifolius that restrict the improvement of yield and quality. Different ratios of biochar combined with mushroom residue were used to improve the soil, clarify its yield-increasing effect and mechanism, and to provide technical support for efficient cultivation of Pandanus. Under basic fertilization, four treatments were set up, 800 kg/hm² mushroom residue (MD), 800 kg/hm² mushroom residue + 1600 kg/hm² biochar (MDB1), 800 kg/hm² mushroom residue +3200 kg/hm² biochar (MDB2), and no mushroom residue or biochar added (CK). A field plot experiment was conducted to study the effects of different treatments on plant growth and yield, soil physicochemical properties and microbial community structure of Pandanus. Compared with CK, the yield increase effect of mushroom residue alone (MD) did not reach a significant level, while the biochar combined application treatments (MDB1, MDB2) significantly increased the fresh leaf yield of P. amaryllifolius. This was related to the significant increase in leaf SPAD value and net photosynthetic rate of MDB1 and MDB2, which significantly increased the average fresh leaf weight, but there was no significant difference in yield between MDB1 and MDB2 treatments. Soil nutrient results showed that compared with CK, MD, MDB1 and MDB2 all significantly increased soil pH and available potassium content, but MD treatment significantly reduced soil organic matter, alkali-hydrolyzable nitrogen and available phosphorus content, which may be related to the utilization of soil organic matter by a large number of organic matter-decomposing microorganisms in the mushroom residue leading to nutrient consumption, while the combined application of high-dose biochar (MDB2) alleviated this effect, thus increasing organic matter content and alkali-hydrolyzable nitrogen content. PCA analysis based on soil bacterial OTUs found that there were significant differences in community structure among different treatments. Compared with CK, MD soil bacterial Shannon diversity index decreased and Simpson dominance index increased, while MDB1 and MDB2 significantly improved soil bacterial diversity. Compared with MD, they significantly increased beneficial plant growth-promoting bacteria such as Pedomicrobium, Streptomyces, MND1, Nocardioides and Pseudomonas. RDA analysis showed that soil alkali-hydrolyzable nitrogen was the main environmental factor affecting bacterial community structure. In summary, although mushroom residue application alone has yield-increasing potential, its effect on soil improvement is poor; combined application of biochar can significantly increase soil pH, available potassium content, improve soil microbial diversity, promote the enrichment of beneficial microorganisms, thereby increasing leaf chlorophyll content, enhancing leaf photosynthesis, and ultimately promoting a significant increase in P. amaryllifolius yield. Therefore, the synergistic application of biochar and mushroom residue is an efficient and safe soil improvement strategy, providing green and sustainable technical support for efficient cultivation of Pandanus.

Ten melon germplasm accessions were treated under simulated low-temperature and weak-light conditions in this study to establish an efficient identification system for low-temperature and weak-light tolerance of melon (Cucumis melo L.) germplasm at the seedling stage. The relative changes in 8 growth indicators (including plant height, stem diameter, leaf area, etc.) and 10 physiological indicators (including chlorophyll content, root activity, relative electrical conductivity, etc.) were determined, and the damage indexs were calculated to initially evaluate the low-temperature and weak-light tolerance of each germplasm. Based on the membership function method in fuzzy mathematics, 19 identification indicators were standardized. Dimensionality reduction was performed via principal component analysis (PCA), and 5 principal components with strong correlations to the low-temperature and weak-light tolerance index, peroxidase (POD) activity, root length, root activity, and soluble protein content were extracted (cumulative contribution rate: 87.026%). Cluster analysis was conducted on the 10 melon germplasm accessions, which were classified into three groups. Group Ⅰ including Vedrantais and M18, was classified as strong low-temperature and weak-light tolerant. Group Ⅱ includding IranH, Topmark, M4 and Nantais oblong, was classified as moderate low-temperature and weak-light tolerant. Group Ⅲ including PI124111, MR1, M76 and PMR5, was classified as weak low-temperature and weak-light tolerant. Finally, stepwise linear regression was used to establish a prediction model for low-temperature and weak-light tolerance of melon at the seedling stage, D=-0.058+0.008X₁₅+0.442X₉+0.058X₁-0.017X₁₉ (R²=0.998, P<0.001), X₁₅ is proline content; X₉ is root length; X₁ is low temperature and low light tolerance index; X₁₉ is peroxidase activity. To verify the reliability of the above identification results, the expression patterns of CmADF1 and CmCYP195 (key genes responding to low-temperature and weak-light stress) were analyzed in germplasm accessions M4, PI124111 and PMR5 at different time points after low-temperature and weak-light treatment. The results showed that the expression characteristics of CmADF1 and CmCYP195 were consistent with the identified low-temperature and weak-light tolerance types of the germplasm, which further confirmed the reliability of the identification system. The results could serve as identification criteria for evaluating low-temperature and weak-light tolerance of different melon germplasm accessions and provide breeding materials for subsequent improvement of melon varieties with low-temperature and weak-light tolerance.

The regulatory effects of exogenous homogentisic acid (HGA) on plant growth, anthocyanin synthesis, and the antioxidant system at phenotypic, physiological and gene expression levels using one-leaf seedlings of Wushansimiao (R534) were studied to explore the role of HGA in rice salt stress response. The results showed that under 140 mmol/L NaCl stress and treatment with 0.25 mmol/L HGA significantly improved the salt tolerance of rice seedlings. On the 3^rd day after treatment, plant height, root length, fresh weight and dry weight increased by 43.95%, 60.00%, 41.86% and 76.38%, respectively, compared to the control without HGA. After 7 days of treatment and 7 days of rewatering, the survival rate of seedlings increased by 56.69%. RT-qPCR analysis revealed that HGA significantly upregulated the key genes involved in anthocyanin biosynthesis in leaves, including OsPAL3, OsCHS8, OsCHI, OsF3H, OsDFR6, OsANS1 and OsUF3GT. Anthocyanin content increased by 15.18%, 24.58% and 39.56% on the 3^rd, 5^th and 7^th day, respectively. On the 3^rd day, the accumulation of reactive oxygen species (H₂O₂ and ) and malondialdehyde (MDA) content decreased, while the activities of antioxidant enzymes SOD, POD and CAT significantly increased. This study preliminarily clarified that HGA could activate the anthocyanin biosynthesis pathway under salt stress to enhance antioxidant capacity, laying a foundation for further understanding the physiological role of HGA.

To investigate the differences in response and labeling efficiency of C₃ and C₄ crops to carbon isotope pulse labeling, this experiment selected C₃ crops (rice and peanut) and C₄ crops (maize and sugarcane) as research subjects. A total of five rounds of ¹³C pulse labeling were conducted in pot experiments to analyze the ¹³C enrichment abundance, fixation amount, and labeling efficiency of the crops, aiming to reveal the differences in carbon fixation and pulse labeling efficiency between C₃ and C₄ crops. The results showed that under labeling treatment, the δ¹³C values and isotope abundance F values of C₃ and C₄ crops showed significant differences, following a consistent pattern: C₃ crops>C₄ crops. The δ¹³C values of the four crop types were as follows: rice (396.90‰-410.05‰)>peanut (269.51‰-364.66‰)>maize (148.15‰-182.47‰)>sugarcane (152.50‰-153.91‰). Under non-labeled treatment, δ¹³C values were as follows: sugarcane (-15.63‰ to -15.16‰)>maize (-18.25‰ to -16.52‰)>rice (-34.53‰ to -33.82‰)=peanut (-35.41‰ to-33.37‰). The ¹³C fixation amount and labeling efficiency showed consistent trends, with no significant differences between C₃ and C₄ crops. Among the four crops, peanut and sugarcane treatments were significantly higher than rice and maize, and peanut was significantly higher than rice. Peanut had the highest labeling efficiency at 46.02%, followed by sugarcane at 33.27%, and rice had the lowest at 24.55%. This study reveals the response differences of C₃ and C₄ crops to ¹³C pulse labeling and provides important data support for the application of stable isotope techniques in crop carbon labeling.

Rubber tree anthracnose is one of the two major foliar diseases of rubber trees, ranking second in severity only to powdery mildew. It has caused significant economic losses to rubber latex production during rubber tree cultivation in China. Against this backdrop, this study focuses on the pathogen of rubber tree anthracnose, investigating its fundamental biological characteristics, molecular identification, antifungal spectrum determination of biocontrol agents, and green prevention strategies. The research begins with a survey of anthracnose incidence in major rubber tree cultivation areas of Hainan province, collecting diseased leaves from rubber forests in Qionghai, Baoting and Chengmai. Pathogenic fungi were isolated and purified, followed by molecular identification and antifungal spectrum analysis by biocontrol agents. Finally, a strain (HZS-BT) isolated from Baoting was subjected to fundamental biological characteristic studies. The findings reveal that, through field surveys of rubber tree anthracnose in various regions of Hainan, it was observed that currently predominant rubber tree varieties in Hainan, such as RY73397, PR107 and RRIM600, exhibit poor resistance to anthracnose under current climatic and ecological conditions. By amplifying core genes, multiplex gene sequencing, and specific primer detection, followed by BLAST comparison with genome sequences of standard strains in the NCBI database, the anthracnose pathogen strain HZS-BT isolated from Baoting was identified as Colletotrichum siamense. The optimal growth temperature for the tested anthracnose strain is 28 ℃, with a preferred pH of 8.0, though the strain demonstrates a broad pH adaptability range. The most suitable carbon and nitrogen sources for its growth are sorbitol and beef extract, respectively. Antifungal spectrum analysis indicates that all 11 biocontrol strains possess potential for biological control applications against anthracnose. This study provides a theoretical foundation for the green prevention of rubber tree anthracnose.

Tetranychus urticae is a significant pest on cassava. Long-term use of abamectin has led to prominent resistance issues. Selecting mite-resistant cassava varieties represents a green, effective and straightforward approach to pest control. However, the effectiveness of resistant cassava varieties against resistant mite strains remains unclear, limiting its utility in supporting resistance management decisions. Accordingly, this study used mite-resistant cassava cultivar C1115, mite-susceptible cassava cultivar SC205 and the preferred host plant cowpea as test materials to investigate the effects on the development, reproduction and detoxification metabolism capabilities of abamectin-resistant (AB-R) and abamectin-sensitive (AB-S) strains. Results showed that compared to feeding on cowpea, feeding on SC205 did not significantly alter the developmental duration or population growth parameters [net reproductive rate (R₀), intrinsic rate of increase (r_m), mean generation time (T), population doubling time (DT)] of either AB-R or AB-S strains. In contrast, feeding on C1115 significantly prolonged the developmental duration and inhibited population growth (significantly decreased R₀ and r_m, significantly increased T and DT) of both strains. Furthermore, on C1115, the T and DT of the AB-R strain were also significantly lower than those of the AB-S strain. Regarding detoxification enzyme activities, compared to feeding on cowpea, feeding on both SC205 and C1115 significantly increased the activities of three detoxification enzymes-cytochrome P450 monooxygenases (P450s), glutathione S-transferases (GSTs) and uridine diphosphate-glycosyltransferases (UGTs) - in both mite strains. Enzyme activities were significantly higher in mites feeding on C1115 compared to those on SC205. Additionally, on all three host plants, the enzyme activities of the AB-R strain were consistently significantly higher than those of the AB-S strain. Detoxification genes associated with abamectin resistance exhibited different expression patterns. Although feeding on both C1115 and SC205 significantly upregulated the expression of six tested genes in both mite strains compared to feeding on cowpea, differences emerged when comparing strains on the same cassava variety. When AB-R and AB-S fed on the same cassava cultivar (C1115 or SC205), the expression levels of CYP389C10, UGT201D3 and UGT11 showed no significant difference. However, the expression of CYP392A16, GSTd01 and GSTm09 was significantly higher in the AB-R strain than in the AB-S strain. The results indicate that the AB-R strain of T. urticae, likely due to its enhanced detoxification capacity, might possess an advantage in neutralizing toxic secondary metabolites from the mite-resistant cassava, potentially compromising the pest control efficacy of this resistant cultivar. This hypothesis, however, requires further validation through subsequent field experiments. This study provides a preliminary theoretical basis for evaluating the application potential of mite-resistant cassava in the management of mite resistance to acaricides.

To address mango leaf disease recognition in complex in-field scenes, where background interference and simultaneous infections across multiple leaves lead to feature recognition difficulties and multi-task segmentation problems, this paper proposes G-Mask2Former, a structure-space-guided model that achieves collaborative segmentation of leaf instances and lesion semantics. The method jointly learns leaf and lesion segmentation within a shared feature space, and leverages a leaf-structure prior to impose spatial constraints on the lesion predictions. First, based on Mask2Former, we use multi-scale pixel representations and mask attention to extract effective features of mango leaf diseases in complex scenes; by constructing pseudo-instances of lesions, we achieve leaf instance segmentation and lesion semantic segmentation within a single model, thereby simplifying model deployment and inference. Second, through a leaf structure-space soft gating module, the model is guided to focus on leaf regions, reducing interference from complex environments. Finally, we conduct experiments on a mango leaf disease dataset collected in complex in-field scenes and perform comparative analyses against other models. The proposed method achieves superior overall performance over classical baselines for segmenting mango leaves and diseases in complex in-field scenes. On the test set, the average precision (AP) for leaf instance segmentation reaches 87.37%, while the mean Intersection-over-Union (mIoU) for lesion semantic segmentation reaches 82.83%. The proposed method would provide an effective solution for mango leaf disease segmentation in complex environments and facilitates quantitative disease assessment.

The study was aimed to screen actinomycetes with good control effects on sugarcane red rot and enrich the resources of biocontrol bacteria for sugarcane red rot. JY53, WK29 and JR28 were screened from sugarcane rhizosphere soil, which showed superior antifungal effects against sugarcane red rot pathogen. They were identified as Streptomyces virginiae, S. iranensis and S. lavendulae, respectively. The antifungal rate of WK29 against six plant pathogens ranged from 68.41% to 78.22%. The antifungal rate of JY53 against five pathogens ranged from 58.66% to 72.85%. The inhibition rates of four plant pathogens by JR28 ranged from 27.69% to 60.15%. All the strains exhibited a certain broad-spectrum activity. Further exploration of the antifungal mechanism revealed that JY53 inhibited pathogen growth by producing β-glucanase, siderophore and volatile substances, while WK29 and JR28 inhibited pathogen growth by producing protease, β-glucanase, cellulase, siderophore and volatile substances. Pot experiment showed that after treatment with the bacterial solution of JY53, WK29 and JR28, the incidence indice of sugarcane red rot was 28.00, 25.33 and 22.67, respectively, significantly lower than 64.00 of the CK, and had a good growth promoting effect. This study indicates that actinomycetes JY53, WK29 and JR28, have certain effects on the prevention and control of sugarcane red rot disease, further enriching the resources of biocontrol bacteria for sugarcane red rot disease.

The inoculation of biocontrol fungi may affect the community structure of microorganisms in the soil, and changes in soil microbial community structure may in turn affect the control effectiveness. This study focused on the most harmful invasive pest, the red imported fire ant Solenopsis invicta Buren. The highly pathogenic Beauveria bassiana strain HHY-B was applied to its nest to reveal the impact of pathogen infection on the nest microbial community structure of the red imported fire ant. The microbiome analysis was conducted on soil samples of B. bassiana infected ant nests after 48 and 96 hours, as well as uninfected ant nests using high-throughput sequencing technology. A total of 648 708 valid bacterial sequences were obtained, belonging to 38 phylum, 127 classes, 274 orders, 451 families and 897 genus. 898 443 fungal sequences were also obtained, belonging to 12 phylum, 38 classes, 88 orders, 197 families, 377 genus. The Proteobacteria and Actinobacteria dominated the soil bacterial community in ant nests. Treatment with B. bassiana significantly increased the relative abundance of Proteobacteria in ant nests (P<0.05), but had no significant effect on the relative abundance of Actinobacteria. Ascomycota dominated the fungal community in the nest soil, and its relative abundance treated with B. bassiana was significantly increased in ant nests (P<0.05). In terms of relative abundance at the genus level, the genus of Beauveria showed an dominate fungi in the two treatment groups, which was not found in the control group. The KEGG pathway analysis showed that the differential bacteria were mainly focused on metabolic pathways, biosynthesis of secondary metabolites, microbial metabolism in various environments, biosynthesis of amino acids, carbon metabolism, two-component systems, ribosomes and other metabolic pathways. The enrichment level of the pathways in the control group was higher than that in the treatment group. This study revealed the changes in the microbial community structure of the red imported fire ant nests after treatment with B. bassiana, which helps to the further understanding of the mechanism of B. bassiana on the red imported fire ants and the living environment, and provides theoretical basis for the biological control for the red imported fire ants.

This study investigated the quality variation and climatic adaptation mechanisms of Hainan large-leaf and Yunnan large-leaf black tea through multi-component analysis and aroma characterization of tea samples from Wuzhishan, Wanning, and Baisha. The results demonstrated that Hainan large-leaf tea exhibited superior photosynthetic performance in Wanning and Wuzhishan, with maximum net photosynthetic rate reaching 7.28 μmol/(m²·s), accompanied by high amino acid content (up to 93.50 μmol/g) and moderate caffeine levels (3.93%-4.31%), forming a distinctive "high amino acid-moderate astringency" flavor profile. Aroma component analysis revealed significant regional differences in Hainan large-leaf tea, with Wanning characterized by benzaldehyde (14.51%)-dominant fruity notes and Baisha featuring linalool (31.18%)-rich floral aroma. Climatic adaptability analysis indicated that higher temperatures in Wanning (annual average 24.40 ℃) promoted the synthesis of tea polyphenols and catechins, while the cooler climate of Baisha (annual average 22.30 ℃) was more conducive to theaflavins formation and aroma compound accumulation. Compared with Yunnan large-leaf tea, Hainan large-leaf tea showed significant advantages in photosynthetic efficiency, amino acid accumulation, and aroma composition. The findings would provide theoretical support for optimizing production regions and developing characteristic products of Hainan black tea, with important implications for enhancing its market competitiveness.

This study systematically analyzed the nutritional composition, active ingredient content, and antioxidant activity of Camellia oleifera Abel. seed cake (COSC) from Yunnan and Jiangxi provinces. The results revealed significant differences in nutritional composition between the two regional samples. COSC from Jiangxi exhibited higher moisture (8.57%), ash (12.31%), and total dietary fiber content (62.73 g/100 g), whereas the Yunnan sample possessed higher levels of crude fat (11.47%), crude protein (12.14%), and total amino acids (0.99 g/100 g). Both samples were rich in beneficial compounds, including vitamin E, vitamin K₃, oleic acid, and linolenic acid. The Yunnan sample contained higher levels of mineral elements such as phosphorus, sulfur, and potassium. Regarding bioactive compounds, Jiangxi COSC showed higher total phenolic (3.29 μg/mg) and total flavonoid (66.75 μg/mg) content, while Yunnan COSC exhibited higher polysaccharide (48.32 μg/mg) and tea saponin (222.10 μg/mg) content. Antioxidant activity analysis indicated that Jiangxi COSC demonstrated stronger DPPH radical scavenging capacity and ferric reducing antioxidant power (FRAP), whereas Yunnan COSC showed superior ABTS cation radical scavenging activity. In summary, Yunnan COSC is suitable for developing high-protein supplements, while Jiangxi COSC is more appropriate for high-fiber feed applications. Both samples exhibited promising antioxidant activity, indicating potential for functional product development. This study would provide a theoretical foundation for the resource utilization and value-added applications of C. oleifera seed cake.