The PYR/PYL/RCAR (PYL) gene family (Pyrabactin Resistance 1/PYR1-Like/Regulatory Component of ABA Receptor), as core receptors of abscisic acid (ABA), play a pivotal regulatory role in the signaling pathways of plant responses to abiotic stresses such as drought. Saccharum spontaneum L. (wild sugarcane), an important wild relative for sugarcane stress-resistant breeding, harbors abundant drought-tolerant genetic resources. However, systematic identification and functional analysis of its PYL gene family remain unreported to date. Based on the S. spontaneum genome data (Saccharum spontaneum Np-X2021), the study identified members of the SsPYL gene family using bioinformatics approaches, and systematically analyzed the physicochemical properties, chromosomal localization, phylogenetic relationships, gene structures, conserved motifs, and cis-acting elements in promoters. Additionally, quantitative real-time PCR (qRT-PCR) was employed to investigate the expression patterns of core members under drought stress. The results showed that 32 SsPYL genes, designated as SsPYL1 to SsPYL32, were identified in the S. spontaneum genome. The encoded proteins ranged in length from 149 to 385 amino acids, with most being acidic and hydrophilic proteins primarily localized in the cytoplasm. The secondary structure was dominated by α-helices and random coils. Furthermore, SsPYLs exhibited uneven distribution across chromosomes, and segmental duplication was the dominant mechanism driving family expansion. A total of 54 pairs of syntenic genes were identified between SsPYLs and rice OsPYL genes, reflecting the evolutionary conservation of this family among monocotyledonous plants. Phylogenetic analysis clustered the 32 SsPYLs into three subfamilies, with members of the same subfamily sharing similar conserved motif compositions and gene structures. All SsPYL proteins contained the signature PYR_PYL_RCAR_like domain. The promoter regions of SsPYL genes were enriched in hormone-responsive and abiotic stress-related cis-acting elements, such as ABRE (ABA-responsive element), ARE (anaerobic responsive element), and LTR (low-temperature responsive element). Under drought stress, the expression levels of eight SsPYL genes (SsPYL1, SsPYL3, SsPYL4, SsPYL6, SsPYL8, SsPYL14, SsPYL19 and SsPYL24) were extremely significantly upregulated (P<0.01), among which SsPYL8, SsPYL14 and SsPYL19 showed more than 5-fold upregulation. The genes are thus speculated to be key candidate genes regulating drought tolerance in S. spontaneum. The study represents the first systematic characterization of the molecular features and drought-responsive patterns of the SsPYL gene family in S. spontaneum. It would provide a theoretical basis for further exploring the functional mechanisms in ABA-mediated drought stress signaling pathways and offer important gene targets for the genetic improvement of drought tolerance in sugarcane.

As an important resource plant in tropical regions, Daemonorops jenkinsiana has significant value in the fields of ecology, economy and medicine. This study investigated the community structure of D. jenkinsiana in the secondary forest of Fanjia Provincial Nature Reserve, Hainan. Through sample plot investigation and analysis, the secondary forest in the Fanjia Provincial Nature Reserve of Hainan served as the research object in this study, revealing its community structure characteristics in detail and providing a theoretical foundation for resource protection and artificial cultivation of D. jenkinsiana., providing theoretical insights for the conservation and sustainable utilization of D. jenkinsiana resources. The D. jenkinsiana community was rich in species composition, encompassing a total of 161 plant species belonging to 134 genera and 69 families. In dominant taxa, the dominant families included Fabaceae, Rubiaceae and Arecaceae, accounting for 47.83% of the total species; the dominant genera were Ficus, Ardisia and Calamus, contributing to 13.66% of the total species. Tropical elements dominated both the families and genera of the plants. Among them, there were 47 tropical families, representing 77.05% of the total families, and 108 tropical genera, accounting for 85.71% of the total genera. The dominant species in the arbor layer were Ficus microcarpa, Heptapleurum heptaphyllum, Phoebe sheareri, Cryptocarya concinna, Quercus glauca, Aporosa dioica, Lannea coromandelica, Camphora officinarum, Zanthoxylum nitidum, Engelhardia roxburghiana. The dominant species in the shrub layer included D. jenkinsiana, Rhapis excelsa, Desmos chinensis, Calamus tetradactylus, Maesa japonica, Calamus egregius, Dypsis lutescens, Psychotria rubra, Ancistrocladus tectorius and Dalbergia hupeana. The dominant species in the herb layer were Rhapis excelsa, Alpinia japonica, D. jenkinsiana, Psychotria rubra, Dalbergia hancei, Maesa japonica, Desmos chinensis, Schima superba, Ardisia crenata and Tetracera asiatica. Species diversity was the highest in the shrub layer and lowest in the herb layer. The D. jenkinsiana community not only serves as a valuable natural subject and sample source for regional biodiversity studies but also supports population regeneration and the long-term maintenance of habitats. Furthermore, it represents a vital natural germplasm repository. By establishing sample banks (e.g., seeds, seedlings, tissue samples from mature plants) and digital information databases (documenting provenance, growth environment parameters, morphological traits, and genetic characteristics), the provenance information for D. jenkinsiana across different species and growth stages can be systematically enriched. The effort holds significant importance for the sustainable management of both cultivated D. jenkinsiana plantations and natural liana communities.

Granule-bound starch synthase I (MeGBSSI) is the key enzyme for amylose synthesis in cassava, primarily responsible for catalyzing the formation of amylose through α-1,4-glucosidic linkages on the surface of starch granules. However, how MeGBSSI cooperates with other starch-synthetic enzymes to orchestrate starch biosynthesis remains unclear. In the previous stage of this research group, through yeast two-hybrid technology, it was hypothesized that the soluble starch synthase MeSSV was a potential binding protein of MeGBSSI. In this study, the MeGBSSI and MeSSV genes were cloned using the main cultivated variety of cassava, Huanshan 8 (SC8), as the material. Yeast two-hybrid vectors pGBKT7-MeGBSSI and pGADT7-MeSSV were constructed. Through yeast two-hybrid point-to-point experiments, the interaction relationship between MeGBSSI and MeSSV was preliminarily verified. The luciferase complementation (LCA) and double-molecule fluorescence complementation (BiFC) techniques were used to further clarify the direct protein interaction between the two. The results showed that the protein sequences encoded by the MeGBSSI and MeSSV genes, compared with the sequenced variety AM560, respectively, had 4 and 2 amino acid substitutions; the MeGBSSI protein was non-toxic to yeast cells and had no self-activation activity; this protein interacted with the soluble starch synthase MeSSV in yeast; the LCA experiment showed that the chemical signals significantly enhanced after co-expression of MeGBSSI and MeSSV; the BiFC experiment further proved that the two could form a complex in plant cells, and the interaction signal was located in the chloroplast. The findings would provide new insight into the synergistic regulation among cassava starch-synthetic enzymes.

Germplasm resources are the key material support for the breeding of new mango varieties and the sustainable development of the industry, and the efficient conservation and utilization are of great significance for mango research. In the study, 431 mango germplasm accessions were used. Combining different sampling strategies and genetic distances, the optimal sampling strategy combination for constructing the mango core collection was screened by the UPGMA clustering method, and the core collection was subsequently established. The results showed that the average effective number of alleles (Ne), average Shannon's information index (I), and average Nei's diversity index (H) of 12 pairs of primers was 4.0993, 1.534 and 0.7361, respectively, indicating that the mango germplasm possessed rich genetic diversity. The t-test results of genetic diversity parameters revealed that the core collection constructed by the combination of the locus priority sampling strategy and Nei & Li genetic distance had the highest Ne, H and I among all tested groups, with value of 4.2603, 0.7486 and 1.5855, respectively, demonstrating that the combination was the optimal method for constructing the mango core collection. The established core collection comprised 85 accessions, accounting for 19.72% of the original germplasm. The retention rate of Ne, I and H in the core collection reached 103.93%, 103.35% and 101.45%, respectively, indicating that although the core collection was much smaller in quantity than the original germplasm, it exhibited superior performance in genetic diversity-related indicators. Principal coordinate analysis (PCoA) showed that the distribution of the core collection uniformly covered the distribution range of the original germplasm in the principal coordinate space, suggesting that the core collection could comprehensively retain the genetic diversity characteristics of the original germplasm and had good representativeness.

Konjac (Amorphophallus spp.) is an important medicine and food economic crop in China, but its industrial development has long been threatened by soft rot disease, known as the konjac 'cancer'. Hainan is an emerging konjac producing area, but the current epidemiological pattern of konjac soft rot disease and pathogenic bacteria population structure is not clarified. The study was aimed to carry out soft rot disease investigation, pathogen isolation and identification, and to provide a scientific basis for the control of the disease. The survey of konjac soft rot disease in six cities and counties in Hainan showed that the highest incidence rate (46.01%) was found in the third team of Danzhou Experimental Farm, while that of Wenchang planting base is low (8.25%). Combining morphology, molecular biology (16S rDNA, proA, gapA and mdh multigene phylogenetic analysis) identifications and distribution information of pathogens, Dickeya fangzhongdai (88.64% of the total), Pectobacterium aroidearum (6.82%) and P. colocasium (4.54%), were the cause of the disease. Pathogenicity assay showed that D. fangzhongdai was high pathogenicity, and indoor screening showed that 0.3% tetramycin had the best inhibitory effect on D. fangzhongdai, with the lowest inhibitory concentration (MIC) of 1.825 μg/mL, followed by 80% ethacrynicin (MIC of 25 μg/mL) and 25% bromoxynil (MIC of 125 μg/mL). The dynamic changes of defence antioxidant enzymes and malondialdehyde in konjac in response to D. fangzhongdai infestation were determined by pot inoculation experiment. The results showed that the activity of superoxide dismutase (SOD) and peroxidase (POD) reached 182.57 U/g and 300.33 U/g, respectively, after 72 h of infestation, which was 2.27-fold and 7.03-fold higher than that of the control, while the activity of catalase (CAT) peaked at 24 h (1093.67 U/g) and decreased to 658.01 U/g in the later period (72 h). Malondialdehyde (MDA) content increased incrementally with infestation time and increased by 30.51% at 72 h compared to the control, and β-galactosidase (β-GAL) activity continued to rise [97 nmol/(min·g)] and increased by 36.86% compared to the control.

The widely targeted metabolisms of fruit pericarp was determined, the differential metabolites were screened and the metabolic pathway was analyzed to understand the metabolomics difference of fruit pericarp at its different growth and development stages in wax apple (Syzygium samarangense). The samples were picked at 15 d (S₁), 30 d (S₂), 45 d (S₃) and 60 d (S₄) after flower respectively. A total of 946 metabolites were detected from wax apple fruit pericarp, including 177 amino acids and their derivatives, 140 flavonoids, 96 sugars and their derivatives, 96 organic acids and their derivatives, 89 lipids, 65 nucleotides and their derivatives, and 283 other metabolites. There were 65, 88, 59, 88, 112, and 103 differential metabolites in S₁ vs S₂, S₂ vs S₃, S₃ vs S₄, S₁ vs S₃, S₁ vs S₄, and S₂ vs S₄ respectively. There were only 6 common differential metabolites in six groups, of which 5 metabolites belonged to amino acids and derivatives and 1 belonged to flavonoid. The differential metabolites of fruit pericarp at different growth and development stages mainly included amino acids and their derivatives, flavonoids, sugars and their derivatives, lipids. The number of differential metabolites of flavonoids, sugars and their derivatives decreased first and then increased, while the number of lipid metabolites increased first and then decreased with the growth and development of fruit. Most flavonoid metabolites were down-regulated, while sugars and their derivatives were up-regulated. There were more lipid differential metabolites in S₂ vs S₃, and only 1 in S₃ vs S₄. The most significant enrichment pathway of differential metabolites of wax apple fruit pericarp were biosynthesis of starch and sucrose, phenylalanine, D-amino acid, galactose, terpenoids and steroids. This study would provide theoretical support and data references for the regulation of fruit quality and harvest period of wax apple.

To address the issues of low added value in traditional pepper processing, poor fluidity of pepper oleoresin, and the incomplete extraction and emulsification techniques for freeze-dried green pepper oleoresin, this study used freeze-dried green pepper as raw material to prepare pepper oleoresin through ultrasonic-microwave assisted extraction. The volatile components were analyzed by gas chromatography-mass spectrometry (with cyclohexanone as the internal standard), and a mixed emulsi-system of Tween 80 and Span 80 was selected to investigate the effects of pH, ionic strength, and water content on the of the emulsion. The results showed that a total of 37 volatile compounds were detected in the pepper oleoresin, mainly monoterpenes and sesquiterpenes, among which β-caryophyllene (210.83 mg/mL) had a relatively high content. The ideal value of the mixed emulsifier was approximately 11. Under the conditions of pH 8.0-9.0, without adding NaCl, and a water content of 95%, the emulsion had a lower particle size and stable physicochemical properties. This study optimized the extraction and emulsification process of freeze-dried green pepper oleoresin, providing technical support for its development and utilization as well as the upgrading of the pepper industry's deep processing.

To enhance the flower quantity and flowering quality of Phalaenopsis, this study investigated the regulatory effects of spraying 6-BA or multi-stem inducer before and after flower stalk emergence on the flowering traits and lateral branch development of different cultivars. The experiment employed one large-flowered cultivar and six small-flowered cultivars. Treatments included spraying 400 mg/L 6-BA or multi-stem inducer (200×dilution) before stalk emergence and 200 mg/L 6-BA after stalk emergence. Flowering indices such as stalk emergence time, double-stalk rate, multiple-stalk rate, stalk length, flower number, number of lateral branches on the stalk, and bud abortion count were measured. Spraying 6-BA or the multi-stem inducer before stalk emergence significantly promoted stalk emergence in small-flowered cultivars, increasing the double-stalk and multiple-stalk rates (e.g., the multiple-stalk rate of 'Jinbian linglong' reached 100%). However, it reduced the number of lateral branches on the stalk in some cultivars. The large-flowered cultivar 'Daliajiao' was insensitive to multi-stalk induction, with a double-stalk rate of only 3.3%, but its stalk emergence time was advanced by 20 days compared to the control after pre-emergence 6-BA treatment. Although spraying 6-BA after stalk emergence delayed flowering, it significantly increased the inflorescence length, flower number, number of lateral branches on the stalk, and the length of the longest lateral branch in small-flowered cultivars. It also induced varying degrees of bud abortion, with 'Jinbian kafei' being the most severely affected, showing a bud abortion rate as high as 59.2%. In conclusion, the effects of 6-BA on Phalaenopsis flowering exhibit significant cultivar differences and are dependent on the application timing. Treatment before stalk emergence is conducive to inducing multiple stalks in small-flowered cultivars and improving emergence uniformity, with the multi-stem inducer showing similar effects to 6-BA. Treatment after stalk emergence can optimize the inflorescence structure of small-flowered cultivars but requires attention to the risk of bud abortion. In production, the appropriate treatment timing should be selected based on cultivar characteristics and cultivation objectives.

Banana has high nutritional and economic value. However, banana is easy to decay after harvest, making preservation difficult. Banana quality is significantly affected by external conditions. Temperature is a key factor in regulating the post-harvest banana ripening quality. Zhongre No. 1 is a new variety resistant to Fusarium wilt with high yield and good quality, which is independently cultivated by our research group. However, its optimal storage temperature has not been clearly defined. Therefore, investigating the effect of different temperature on the post-harvest quality of Zhongre No. 1 is of great significance for the industrialization of the variety. In the study, freshly harvested Zhongre No. 1 banana was ripened at 14 ℃, 16 ℃, 18 ℃, 20 ℃, 22 ℃ and 25 ℃, respectively. Aimed at determining the optimal preservation temperature, the ripening characteristics and starch degradation dynamics were systematically observed, and indicators such as weight loss rate, peel color difference, ethylene release amount, firmness, and starch and sugar content were measured to analyze the effect of storage temperature on the quality indicators. The results showed that higher temperature led to faster fruit color change, weight loss, bunch separation, ethylene release, softening, and starch degradation. Different temperature had little effect on fructose and glucose content but significantly affected sucrose content, with the sucrose content in 22 ℃ and 25 ℃ being significantly higher than that at 14 ℃ and 18 ℃, among which 22 ℃ had the highest sucrose content and 14 ℃ had the lowest. Banana stored at 14 ℃ had the strongest storability, with stable color after turning yellow, making them suitable for long-term storage and transportation. Banana at 22 ℃ ripened quickly and had high sweetness but poor color. Banana at 18 ℃ ripened relatively quickly with golden and plump fruit color, making it more suitable for rapid shelf placement and sales. Banana at 25 ℃ failed to normally lose green color, was easy to bunch separation, and lost commercial value.

Tomato ripening involves the coordinated regulation of key agronomic traits such as color transformation, texture softening, and flavor compound accumulation. Elucidating its molecular mechanisms is not only a central goal in postharvest biology but also crucial for improving fruit quality and achieving precise control of storage duration. In this study, the functions of SlBEL1, SlBEL2 and SlBEL11, members of the BEL family of transcription factors in tomato, were systematically investigated through multi-dimensional experiments. Phylogenetic and amino acid sequence alignment analyses revealed that SlBEL1, SlBEL2 and SlBEL11 possessed highly conserved protein domains, suggesting potential functional similarities. Spatiotemporal expression profiling showed that the genes were synchronously highly expressed during critical stages of fruit ripening, from the breaker to the full ripening stage. Using CRISPR-Cas9 technology, single-gene and triple-gene editing lines of SlBEL1, SlBEL2 and SlBEL11 were generated. The single-gene editing lines CR-SlBEL1, CR-SlBEL2 and CR-SlBEL11 all exhibited a delayed fruit ripening phenotype, while the triple editing line resulted in impaired reproductive development, failing to proceed to flowering and fruit setting. Furthermore, reverse transcription quantitative real-time PCR (qRT-PCR) analysis revealed that SlBEL1/2/11 modulated the expression of multiple ripening-related genes in tomato. Collectively, the results demonstrate that SlBEL1/2/11 functioned redundantly to coordinately control the fruit ripening process. This study identified novel targets for the genetic improvement of tomato fruit ripening.