The induction of adventitious roots (AR) is a key step for successful clonal propagation in plants. Previous studies have shown that the auxin polar transport carrier MiPIN1 plays an important role in AR formation from mango cotyledon segments, yet its upstream regulatory mechanisms remain unclear. In this study, a 2 112 bp promoter sequence of MiPIN1 isolated using FPNI-PCR. Bioinformatic analysis revealed that the promoter region contained various cis-acting elements, including those involved in light response, MYB binding, abscisic acid response, and low-temperature stress. A bait vector, pAbAi-MiPIN1, was constructed, and the minimal concentration of Aureobasidin A (AbA) required to suppress autoactivation in the yeast system was determined to be 500 ng/mL. Furthermore, a yeast cDNA library was constructed from mango cotyledon segments during AR formation. Using the yeast one-hybrid (Y1H) system, 62 upstream proteins that potentially bind to the MiPIN1 promoter were identified, including auxin-binding protein ABP19a-like, zinc finger protein CCCH, MYB308, 8-hydroxygeraniol dehydrogenase, and chlorophyll a-b binding protein LHCII. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses indicated that the proteins were mainly involved in biological processes such as cellular processes, metabolism, response to stimuli, and biological regulation. They were also enriched in metabolic pathways related to secondary metabolite biosynthesis, energy metabolism, and the metabolism of amino acids, lipids, and carbohydrates. The findings would lay a foundation for unraveling the molecular regulatory network underlying adventitious root formation in mango.

Mango is one of the most widely cultivated and economically significant fruit trees in tropical regions of China, playing a vital role in optimizing agricultural structure and promoting rural revitalization. Scientifically delineating suitable planting zones for mango is essential for precise resource allocation and the high-quality development of the industry. However, most existing studies focus on climatic and topographic factors, with insufficient systematic consideration of soil physicochemical properties. In addition, current suitability evaluations often suffer from strong subjectivity in indicator selection and low integration of evaluation methods. To address these gaps, this study took Sanya city as the research area and developed a comprehensive evaluation model for mango planting suitability. First, the MaxEnt model was employed to identify key environmental factors and extract response curves for constructing membership functions. Second, an improved three-scale Analytic Hierarchy Process (3-scale AHP) and the entropy weight method were applied to determine subjective and objective weights, respectively, which were then integrated using a game theory-based weighting approach. Finally, the study area was classified into three planting suitability zones based on a comprehensive suitability index, and field surveys were conducted for validation. Bulk density, pH, cation exchange capacity (CEC), silt content, total potassium, soil type, slope, elevation, sunshine hours during the fruit maturity and harvest period, and annual maximum temperature were the ten dominant factors, with soil-related variables playing a critical role in the model. The suitable area covered 117 939 hm², accounting for 61% of Sanya's total area, with the most advantageous zones concentrated in southern Yazhou and southern Tianya. Advantageous zones were characterized by "low elevation–slightly acidic–potassium-rich–high permeability–high sunshine" conditions, which are conducive to high and stable mango yields with premium quality. The "factor selection–membership function construction–game theory-based weighting–suitability zoning" evaluation framework proposed in this study would provide both theoretical and methodological support for precision planting of tropical fruit trees and the optimization of regional agricultural spatial layouts.

Lodging resistance is an important trait in sugarcane breeding. Accurate evaluation of the lodging resistance of germplasm resources is of great significance for breeding lodging-resistant varieties. This study investigated the effects of agronomic traits and stalk fiber components on lodging resistance using 16 sugarcane germplasm materials. The key traits affecting lodging resistance were identified by grey correlation analysis, and the comprehensive evaluation was carried out by using membership function method and cluster analysis method to screen excellent lodging resistance germplasm and its key traits, so as to provide germplasm resources and theoretical reference for sugarcane lodging resistance breeding. The results showed that the sugarcane germplasm materials with the strongest lodging resistance were Yunzhe 17501, Guiliu 05136 and Yuetang 93159. Among them, stem diameter, effective stem number, plant height and cellulose content were the key factors affecting the lodging resistance of sugarcane.

Intercropping within rubber plantations presents an effective strategy to counteract the financial challenges posed by sustained low prices of natural rubber and widespread cultivation losses. The success of the intercropping systems is critically dependent on understory light availability, which serves as a key driving factor. A thorough analysis of the variations in understory light conditions among different rubber clones and the underlying causes is essential for providing a theoretical basis for optimal clone selection and system design. This study investigated rubber plantations featuring various clones, tree ages, and planting patterns. The understory light intensity were measured and compared. Unmanned Aerial Vehicle LiDAR point clouds were used to extract key tree architecture parameters to determine the architectural drivers of light variability. Findings revealed significant differences in understory light intensity attributable to clone type, tree age, and planting pattern. Notably, the Reken 628 clone consistently provided significantly higher understory light levels across all ages and row orientations compared to other clones like CATAS 72059, and CATAS 73397. UAV-derived data confirmed that Reken 628 plantations exhibited larger inter-row gaps and significantly lower canopy closure. Architectural analysis further elucidated that Reken 628 was characterized by a taller stature, higher branching, a smaller crown length ratio, and a more compact, sparser crown structure with fewer, smaller-angled primary branches. This clone also displayed pronounced natural self-pruning, which collectively contributes to its low canopy closure. Conversely, CATAS 73397 features a wider crown, a higher crown length ratio, more numerous and wider-angled branches, and severe crown overlap, resulting in high canopy closure. In conclusion, considering its favorable tree architecture and the resultant superior light conditions, Reken 628 is identified as an excellent clone for intercropping systems. This research holds significant practical value for advancing the adoption and sustainable development of intercropping in rubber plantations.

Fruit quality is the key indicator to measure the commodity value of fruit, and the indicators such as single fruit weight, fruit shape and fruit determination degree (DD) are particularly crucial, which directly affect consumers' desire to buy. In addition, primary metabolites are indispensable substances in the process of plant growth and development, which are widely present in all plants, providing basal metabolites and energy support for plant growth, development and reproduction. Primary metabolites such as sugars, organic acids, amino acids and inositol are the key factors affecting fruit quality, and they are also important criteria for measuring fruit flavor and texture. With the improvement of consumers' living standards and the pursuit of healthy fruits, a large amount of data is needed to screen out Annona squamosa varieties with high nutritional value and high sugar. Yunnan's hot and dry valley climate provides an excellent environment for the fruit to thrive. In order to explore the differences in fruit quality and the composition and content of primary metabolites in the pulp of the four varieties of A. squamosa in the dry and hot river valley of Yunnan Province, the varieties with high nutritional value and high sugar were screened. Four varieties (AP, Damu, Fengli and Liulian) from the planting base of Yuanjiang County, Yuxi City, Yunnan Province were used as the test materials. Gas chromatography-mass spectrometry (GC-MS) was used to determine the composition and content of primary metabolites per unit weight of fresh fruit pulp, and the one-way analysis of variance (ANOVA), principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used for comprehensive analysis and evaluation. Among the four cultivars in the dry-hot valley area of Yunnan, AP A. squamosa had the largest single fruit weight. The content of soluble solids (TSS) in Liulian A. squamosa was the highest. The fruit shape of the Damu A. squamosa is oval, and the other three varieties are oblong; The fruit DD of Fengli A. squamosa was the smallest, and there was no significant difference among the other three cultivars. A total of 43 primary metabolites were detected in the pulp of the four cultivars, including 9 amino acids, 13 organic acids, inositol and 20 soluble sugars. Further analysis of the contents of various primary metabolites in the pulp of the four varieties showed that the contents of sucrose, fructose, glucose, allulose, citric acid and malic acid were the main among the 43 primary metabolites. The contents of glucose, allulose, citric acid and malic acid in Liulian A. squamosa were significantly higher than those of other varieties, and the contents of sucrose and fructose in AP A. squamosa were significantly higher than those of other varieties. In addition, some primary metabolites had significant cultivarity specificity, among which leucine, acetamide acid, xylulose and threonate were only detected in AP A. squamosa. Trehalose is only detected in Liulian A. squamosa. Principal component analysis (PCA) showed that the variance contribution rate of PC1 was 48.3%, that of PC2 was 25.8%, and that of cumulative variance was 74.1%. Partial least squares discriminant analysis (PLS-DA) was used to screen 19 primary metabolites as the characteristic differential metabolites in VIP≥1, including 5 amino acids, serine, L-hydroxyproline, leucine, L-norvaline and L-glutamic acid. 2 organic acids, acetamide and 2-ketoglutarate; 7 soluble sugars, namely D-(+)-xylose, D-arabinose, hexapyranose, xylulose, L-threonose, L-(-)-fucose, sucrose, d-galactose, D-(+)-pinedisinose, maltose and D-(+)-cellobiose; and inositol. From the perspective of basic quality and primary metabolite level, the fruit TSS and primary metabolite content of Liulian A. squamosa were the highest, while the TSS of Fengli A. squamosa was moderate and the outer gauge was the most regular. Therefore, the two varieties can be promoted and planted as A. squamosa varieties with high nutritional value and high sugar in dry and hot river valleys.

This study investigated the differences in soil physicochemical properties under three different land-use types, eucalyptus forest, orchard and rubber plantation, developed from granite-derived soils in Danzhou city, Hainan province. The results demonstrated that land use significantly influenced soil nutrient and acidity characteristics: rubber plantation soils showed significantly higher organic matter and total nitrogen content compared to other land uses, but also the most severe acidification with exchangeable aluminum content approximately 3.06 and 3.53 times higher than that in eucalyptus forests and orchards; Orchard soils were characterized by abnormal phosphorus enrichment, with available phosphorus content about 5.62 and 10.46 times higher than that in rubber plantations and eucalyptus forests, respectively, accompanied by strong base cation leaching and the lowest cation exchange capacity (CEC); Soils in Eucalyptus forests exhibited intermediate properties with relatively milder acidification. In terms of soil structure, rubber plantations were dominated by >5 mm aggregates. Combined with its most severe acidification and highest exchangeable aluminum content, this aggregate distribution pattern may indicate poor stability of large aggregates under strong acid and high aluminum toxicity environments. Although rubber plantation soils had CEC values approximately 2.47 and 3.02 times higher than those in Eucalyptus forests and orchards, respectively, the base saturation was extremely low, reflecting a significant contradiction between nutrient retention capacity and actual fertility availability. This study preliminarily suggests that the accumulation of high organic matter in rubber plantation soils may be associated with substantial litter input from rubber trees, while strong acidification and high aluminum toxicity are likely driven by continuous nitrogen cycling processes. The phosphorus enrichment in orchards primarily results from long-term excessive phosphorus fertilization. These findings provide a scientific basis for soil management and acidification control in tropical granite-derived regions under different land-use types.

The purpose of this study was to investigate the mechanism and efficacy of Lvnonglin ^®41 compound microbial fertilizer in mitigating black pepper continuous cropping obstacles from the perspectives of soil nutrients, microbial community structure and diversity, so as to provide technical strategies for the industrial cultivation of black pepper in Hainan. Field experiments were conducted on a plot with a history of severe black pepper Fusarium wilt. Four treatments were designed: water control (CK), Lvnonglin^® 41 compound microbial fertilizer (LNL41), compound microorganisms (CM), and bacterial fertilizer nutrient substrate (NS). The incidence of Fusarium wilt in the rhizosphere, plant growth and soil nutrients were measured. Using 16S rDNA sequencing technology, the differences in the occurrence of black pepper Fusarium wilt and the bacterial community structure in the rhizosphere soil under LNL41 application were explored. The results showed that compared with CK, all treatments exhibited certain effects, with the LNL41 treatment being the most effective. Soil nutrient indicators in the LNL41 and CM treatments were significantly higher than those in CK. The increases in chlorophyll content, spike length and 1000-grain weight under LNL41, CM and NS treatments reached 26.12%–67.87%, 6.20%–18.33% and 1.48%–6.44%, respectively. The incidence rates at different growth stages in the LNL41 treatment were 2.67%–15.67%, with control efficacies of 81.64%–90.06%. The Ace and Chao1 indices of rhizosphere soil bacteria increased by 12.82%–20.28% and 12.89%–18.78%, respectively, and the Shannon diversity index increased by 1.05%–3.53%, while the Simpson index showed no significant difference among treatments. At the order level, Chitinophagales, Rhizobiales and Burkholderiales were the dominant bacterial orders. At the genus level, Gaiella, P3OB 42, Lactobacillus, Pseudolabrys and Terrimonas were the dominant bacterial genera. The abundances of the common dominant genus Bacillus and Candidatus Omnitrophus were similar across treatments. Linear discriminant analysis (LEfSe) results indicated the presence of six indicator bacterial taxa in the LNL41 treatment. Ellin6067 and Tepidisphaera showed significant or highly significant positive correlations with soil pH, organic matter, available potassium, ammonium nitrogen and available phosphorus. Network analysis further revealed that the LNL41 treatment enhanced the complexity and stability of the soil bacterial co-occurrence network. Bugbase functional prediction demonstrated that the abundance of stress tolerant functional groups in the LNL41 treatment increased by 5.38 percentage points, while it decreased by 10.43 and 7.25 percentage points in the CM and NS treatments, respectively. LNL41 significantly improved the ratio of soil nutrients, thereby enhancing the structure and functional characteristics of the soil bacterial community, stimulating bacterial stress tolerance functions, promoting black pepper growth, and reducing the incidence of Fusarium wilt.

The study analyzed the soil chemical properties, nutrient contents and distribution characteristics in the litchi gardens from the major growing regions in Yunnan aimed to provide supports for nutrient and fertilization management in litchi gardens. Soil samples were collected from 22 litchi gardens in 6 major production regions. Soil pH, organic matter and multi-elements content were analyzed and used as the indicators to evaluate soil fertility via fuzzy comprehensive analysis. The results showed that soil pH was 5.62, with 22.73% of soil samples were suitable for litchi growth (pH=5.0~5.5). The cation exchange capacity (CEC) of 27.28% of soils was lower than 10.00 cmol/kg, indicating fertilizer retention ability should be improved. Organic matter content was relatively high (14.81-57.06 g/kg). Soil total N content (0.84-2.70 g/kg) was higher than medium level (>1.00 g/kg) excepting for Baoshan region. Soil alkaline hydrolyzed N (78.61-259.19 mg/kg), available P (21.14-92.48 mg/kg) and available K (35.00-642.50 mg/kg) were all higher than medium level excepting one orchard in Yongde, where the available K content (36.67 mg/kg) was at deficiency level (<50.00 mg/kg). Among the trace elements, available Ca (415.63-4900.00 mg/kg) and available S (20.43-127.89 mg/kg) were relatively abundant. Soil available Mg (3.13-512.50 mg/kg) was at moderate level, with 42.43% of samples were below the limit value (<100.00 mg/kg). Available Zn (0.51-9.68 mg/kg) and available Fe (7.18-124.82 mg/kg) were abundant. Available Mn (2.56-104.78 mg/kg) and available Cu (0.76-6.06 mg/kg) were at moderate level, with 8.60% of the samples showing available Mn lowering than 5.00 mg/kg. Available B and Mo were at sufficient level in Yingjiang at 0.88 and 0.43 mg/kg, while those in Pingbian (B: 0.44 mg/kg, Mo: 0.13 mg/kg), Yuanyang (B: 0.31 mg/kg, Mo: 0.15 mg/kg), Baoshan (Mo: 0.10 mg/kg), Yongde (B: 0.42 mg/kg, Mo: 0.10 mg/kg) and Xinping (B: 0.41 mg/kg, Mo: 0.10 mg/kg) were at deficient levels. The integrated fertility index (IFI) was 0.51-0.97, with average value at 0.79. All IFI values were above level II excepting Baoshan region at level III. The principal component analysis showed that total N, alkaline hydrolyzed N, organic matter and pH were the most important factors affecting soil fertility. The data suggested that the overall soil fertility of the studied 22 litchi gardens was above the medium level. Mg and Mo fertilizers can be improved in Baoshan, and B and Mo fertilizers can be improved in Pingbian, Yuanyang, Yongde and Xinping.

With the aim of obtaining a new type of green fungicide that is low-cost, safe and highly efficient, this study investigated the antibacterial activity of Cinnamon leaf essential oil and its feasibility as a quorum sensing inhibitor (QSI), and explored its biocontrol effect on bacterial soft rot disease. In this study, the chemical composition of Cinnamon leaf essential oil was analyzed by gas chromatography-mass spectrometry (GC-MS), and the effect of Cinnamon leaf essential oil on the biological control of bacterial soft rot disease was studied, and the effect of Cinnamon leaf essential oil on inhibiting the soft rot pathogen Dickeya fangzhongdai Onc5 quorum sensing system was determined. It was indicated that a total of 16 major constituents were identified in Cinnamon essential oil and the main components were isopropyl palmitate (52.15%), cinnamaldehyde (23.02%) and isopropyl myristic acid (18.80%). Broad-spectrum antibacterial tests showed that the Cinnamon essential oil extracted from leaves had a significant inhibitory effect on five types of bacteria, including Chromobacterum violaceum ATCC31532, Pectobacterium carotovorum subsp. carotovorum, Escherichia coli ATCC25922, Serratia marcescens H30, and D. fangzhongdai Onc5. The minimum inhibitory concentration (MIC) of Cinnamon essential oil against the soft rot pathogen Onc5 was determined to be 2.5‰. Without affecting the normal growth of D. fangzhongdai Onc5, Cinnamon essential oil could weaken its flagellar motility and the release of PCWDEs, controlled the swimming and swarming of D. fangzhongdai Onc5, and effectively inhibited the soft rot pathogen. At sub-inhibitory concentrations (1/2MIC and 1/4MIC), Cinnamon essential oil was able to inhibit the activity of the plant cell wall degrading enzymes (Cel, Pel, Prt) of D. fangzhongdai Onc5, thereby limiting the ability of pathogen to invade plant cells. In order to further verify the antibacterial effect of Cinnamon essential oil, D. fangzhongdai Onc5 treated with 1/2MIC Cinnamon essential oil was inoculated on carrots, cabbage, potatoes and white radishes, and the results revealed that the pathogenicity of the bacterial liquid attenuated significantly. The research found that Cinnamon leaf essential oil exerts antibacterial effects by reducing the secretion activity of extracellular degrading enzymes and flagellar motility of D. fangzhongdai Onc5, thereby influencing its quorum sensing system. It has application prospects employed to control postharvest soft rot in fruits and vegetables as biological means, providing theoretical basis and technical support for the preservation of agricultural products and the green prevention and control of diseases.

This study aimed to investigate the effects of the root exudates from Cyperus rotundus, a common weed in Guizhou tabacco fields, on the tobacco bacterial wilt pathogen Ralstonia solanacearum strain AS-1 and the biocontrol agent Bacillus velezensis strain JXF-16. Non-targeted metabolomics (LC-MS) was employed to identify the chemical composition of C. rotundus root exudates and to explore the effects of specific bioactive constituents on the two bacterial strains. Turbidimetric assays were used to measure the impact of the active compounds on bacterial growth, crystal violet staining was applied to quantify biofilm formation, and semi-solid plate culture assays were conducted to assess bacterial motility. Additionally, pot experiments were performed to evaluate the efficacy of the exogenous active compounds in controlling bacterial wilt. Results revealed that a total of 21 types of chemical compounds and 3176 active substances were detected by LC-MS. At the concentration of 50 μmol/L, myristic acid, 4-ethyloctanoic acid, ligustrazine and betaine significantly promoted the growth, biofilm formation and motility of R. solanacearum. However, at higher concentrations, the compounds exhibited inhibitory effects on bacterial growth and biofilm formation. Tetramethylpyrazine (50 μmol/L) and betaine (100 μmol/L) significantly enhanced the growth, biofilm formation and motility of B. velezensis. Conversely, lauric acid and 2-dodecylbenzenesulfonic acid at concentrations above 50 μmol/L significantly inhibited the growth, biofilm formation, and motility of both R. solanacearum and B. velezensis. Pot experiments demonstrated that lauric acid and 2-dodecylbenzenesulfonic acid at 150 μmol/L and 200 μmol/L effectively controlled bacterial wilt, with the relative control efficacies surpassing those of chemical pesticides and biocontrol agents. Notably, 2-dodecylbenzenesulfonic acid at 200 μmol/L achieved a control efficacy of 80.28%. The results would provide important theoretical insights into the role of C. rotundus root exudates within the tobacco field ecosystem and lay an applied foundation for developing novel bioactive compound-based strategies to control tobacco bacterial wilt.