Diversity, correlation, cluster analysis and principal component analysis were condunted on 16 quantitative traits and 13 qualitative traits of 124 germplasm resources of Abelmoschus esculentus to clarify the genetic diversity and phenotypic traits of A. esculentus germplasm resources, and to provide a reference basis for the identification, evaluation, and innovative utilization of A. esculentus resources. The coefficient of variation of the 16 quantitative traits ranged from 8.2% to 59.8%, with an average coefficient of variation of 18.7%. The genetic diversity index ranged from 1.51 to 2.07, with an average of 1.94. The diversity index of qualitative traits ranged from 0.08 to 1.52. The diversity of fruit color, leaf color and leaf margin morphology was relatively high, while traits such as petal color and sepal retention were highly conservative. Correlation analysis showed that there was a close synergistic relationship among the leaf morphology (such as leaf length and leaf width), plant structure (such as plant height and plant width) and fruit characteristics (such as fruit longitudinal diameter and weight) of A. esculentus, while there was an antagonistic relationship among yield-related traits (number of fruits per plant and number of seeds). Principal component analysis simplified the 16 quantitative traits into 4 principal components, with a cumulative contribution rate of 99.25%. The contribution rate of the first principal component was 96.17%, indicating that plant height, plant width, commercial fruit length, commercial fruit width, fruit weight, and seed number per fruit had the greatest impact on phenotypic diversity. Based on the cluster analysis of Euclidean distance, the germplasm resources of A. esculentus were divided into four major groups. Group Ⅰ accounted for 70.16% of the resources and was mainly characterized by early maturity (short flowering period), low flowering node, short plant height, small plant width, and a high number of fruits per plant. This group was suitable for breeding new varieties with early maturity, high yield, and dense planting. Group Ⅱ accounted for 25.81% of the resources and was characterized by larger fruits, heavier single fruit weight, and larger leaves, which could be used for breeding mid-season varieties. Group Ⅲ and Group Ⅳ were primarily characterized by late maturity, taller plant height, larger leaves, and higher biomass yield, making them suitable for breeding feed-purpose varieties. Through quantitative and qualitative trait analyses of genetic diversity in okra germplasm resources, as well as principal component analysis and cluster analysis, the genetic variation, correlations, and genetic diversity relationships among various traits were elucidated. This study identified traits associated with early maturity and high yield, laying a foundation for the conservation and efficient utilization of okra germplasm resources, as well as for breeding new early-maturing and high-yielding varieties.

Albino plants lacking photosynthetic pigments are ideal materials for studying photosynthesis. In this study, albino Artocarpus heterophyllus seedlings (AAS) were found during the preliminary investigation. AAS have larger leaves, longer survival time and stable phenotypic traits, so it is a rare woody plant albino material. The expression of photosynthesis-related genes were analyzed through transcriptome sequencing technology and found that the expression of many genes in photosynthetic pigment synthesis, photosynthesis-antenna protein, photoreaction and carbon fixation reaction pathways were down-regulated in AAS leaf, also the expression of genes encoding heat shock protein 70 (HSP70), heat shock protein 90 (HSP90) and HSP70-HSP90-organizing protein 3 (HOP3), which are considered to be key regulators in the plastid-nuclear signaling pathway, were up-regulated. This study discussed the cause of AAS from the synthesis pathway of photosynthetic pigment, and also discussed the expression of photosynthesis-related genes from the aspect of plastid-nuclear signal, which can provide reference for the research of this retrograde signaling pathway.

Crotalaria pallida is an annual diploid self-pollinating plant of the genus Crotalaria in the Fabaceae family. It was described and published by WILLIAM TOWNSEND in 1789. Geographical studies believe that the species originated in the southeastern part of the Africa continent and Madagascar. Biologically, the species have the characteristics of high seed yield, wide adaptability, and fast growth, which makes it widely spread and distributed in tropical and subtropical regions around the world. The wide distribution has attracted the attention of ethnobotany and natural science research. It is generally believed that it is an important agricultural plant resource with great development potential in feed development, soil ecological restoration, and medicinal development. However, the utilization of C. pallida has always relied on wild resources, and research on accurate evaluation of germplasm resources, mining of genetic diversity, and breeding of excellent varieties is limited. This article reviews the research progress in the global distribution, biological learning, cultivation technology, feed value evaluation, soil nutrient maintenance, and medicinal value evaluation of C. pallida, and summarizes the current problems and future research directions, aiming to provide an important reference for promoting the research on the utilization.

The effects of spraying different combinations of plant growth regulators and foliar fertilizers at the appropriate fruit-setting time on the fruit expansion and quality of seedless fruits of Tainong No.1 mango were studied to provide a scientific basis for the high-quality and high-yield cultivation techniques of seedless fruits of Tainong No.1 mango, and to offer a reference for the scientific application of fertilizers for the expansion of seedless fruits of other small-and medium-sized mangoes. From 2022 to 2024, the seedless fruits of Tainong No.1 mango were used and four foliar spraying treatment schemes were set up, the control group (CK) with foliar fertilizer, T₁ treatment with gibberellic acid + foliar fertilizer, T₂ treatment with gibberellic acid + plant growth regulator + foliar fertilizer, and T₃ treatment with compound plant growth regulator product + foliar fertilizer. The growth and development and fruit quality indicators of the seedless fruits were measured and analyzed. The results showed that when the fruits were 6-10 mm in size, spraying gibberellic acid + plant growth regulator + foliar fertilizer four times, the single-fruit weight of green fruits in T₁ and T₃ treatments was greater than 100 g, while the average single-fruit weight of green fruits in CK was 67.55 g, and the fruit-expanding effect was obvious. Among them, the average single-fruit weight of green fruits in T₃ treatment increased by 98.98% compared with CK. T₁ and T₃ treatments significantly increased the calcium content. T₁ and T₃ treatments significantly decreased the average density, weight loss rate, total acid content, and vitamin C content of green fruits. T₁ and T₃ treatments had no significant effect on the fruit shape index. T₂ treatment significantly decreased the soluble solid content, while T₁ and T₃ treatments had no significant effect on the soluble solid content. T₁ and T₃ treatments significantly increased the solid-acid ratio. Among them, T₁ treatment significantly increased the solid-acid ratio, which was 45.34% higher than CK, and T₂ treatment had no significant effect on the solid-acid ratio. T₁ and T₃ treatments significantly increased the magnesium content, while T₂ treatment had no significant effect on the magnesium content. T₁ and T₂ treatments significantly decreased the potassium content, while T₃ treatment had no significant effect on the potassium content. No residues of the used plant growth regulators were detected in the fruits. 1 mango in each treatment. Comprehensive score of the fruit quality of the fruits revealed the fruit quality of T₁ treatment was the best, followed by T₃ treatment. However, the single-fruit weight of T₁ treatment after full ripening was less than 100 g, which could not fully meet the market's requirement for single-fruit weight. The fertilizer combination of T₃ treatment is recommended for the production of seedless fruits of Tainong No.1 mango.

Seed shattering is the main reason for the continuous self-reproduction and spread of weedy rice in rice fields. Genes SH4 and qSH1 are considered to be the main genes controlling rice seed shattering. The aim of this study was to determine the genotype of the seed shattering SNP locus at SH4 and qSH1 of weedy rice in Hainan. Using weedy rice from rice fields in Lingao and Yazhou District as research materials, this study collected weedy rice and corresponding cultivated rice seeds from 13 rice fields. 144 Weedy rice seeds with different phenotypes and 13 corresponding cultivated rice seeds were selected for germination and planting, and the seed shattering rates were measured. PCR amplification and sequence analysis were performed on the seed shattering SNP locus at SH4 and qSH1. The results showed that there were 77 wild type (G) weedy rice plants, 48 mutant type (T) weedy rice plants, and 19 heterozygous type (G/T) weedy rice plants with the locus at SH4 gene; Seed shattering SNP locus of SH4 gene in all cultivated rice samples were T. The determination of seed shattering rate found that 96 weedy rice samples with G and G/T genotype seed shattering SNP at SH4 gene had extremely high seed shattering rates, while among 48 weedy rice samples with T genotype seed shattering SNP locus at SH4 gene, 40 weedy rice samples had moderate seed shattering rates and 8 weedy rice samples had low seed shattering rates. Seed shattering SNP locus of qSH1 in all weedy rice and cultivated rice samples were wild-type seed shattering G genotype. The above results indicate that the difference in seed shattering rate between Hainan weedy rice and cultivated rice is not related to the seed shattering SNP locus at qSH1 gene, but significantly correlated with the seed shattering SNP locus at SH4 gene. The difference in seed shattering rate between weedy rice and cultivated rice with T genotype SNP locus at SH4 gene may be caused by differences in other unknown genes or locus. This study would provide a molecular basis for the seed shattering mechanism of weedy rice in Hainan.

STAY-GREEN (SGR) is a key gene that regulates chlorophyll degradation in plants and plays an important role in controlling plant senescence. To investigate the regulatory role of the SGR gene in the fruit coloration process of pepper, the homologous gene cloning method was employed to amplify the CaSGR gene from pepper fruit cDNA using PCR technology in this study. Bioinformatics analysis was conducted on its protein sequence, and a virus-induced gene silencing (VIGS) vector was constructed to preliminarily verify the gene function. The results showed that ORF of CaSGR was 792 bp, encoding 263 amino acids. Bioinformatics analysis revealed that SGR was relatively conserved among Solanaceae crops, and SGR had a closer evolutionary relationship with SGR from tomato and potato. CaSGR VIGS vector was constructed and injected into pepper leaves, successfully obtaining silenced plants. The silenced plants exhibited leaf whitening, fruit color changed, and CaSGR expression levels reduced significantly. Additionally, the chlorophyll and β-carotene content in the fruits of the silenced plants increased markedly. This study would provide a foundation for further elucidating the molecular regulatory mechanisms of CaSGR in pepper fruit coloration and offer theoretical support for breeding new pepper varieties with high carotenoid content.

Evapotranspiration as a key component of the energy balance and hydrological cycle, not only plays an important supporting role in ecosystem stability and water resource management, but is also a crucial indicator for evaluating agricultural water use efficiency. Obtaining high spatiotemporal resolution data can reveal the dynamics of evapotranspiration, which is of great significance for analyzing ecological and hydrological processes. The region studied is rubber plantations in Danzhou city, Hainan province. Based on daily meteorological data from flux tower observations and ten corresponding scenes of Landsat 8 satellite imagery for the same period, the daily evapotranspiration of the rubber plantations in 2022 was estimated using the surface energy balance system (SEBS) model, and the results were validated for accuracy using the eddy covariance method. The results showed that the SEBS estimated daily evapotranspiration values from rubber plantations had a good correlation with the eddy covariance measured values (R²=0.88, RMSE=0.55, RE=18.95%). The daily evapotranspiration exhibited significant seasonal variation, showing that the wet season was significantly higher than the dry season. The maximum daily evapotranspiration occurred on July 31, reaching 4.40 mm, while the minimum daily evapotranspiration occured on January 28 and March 9, both at 1.38 mm. The accuracy of evapotranspiration derived from Landsat 8 imagery was influenced by factors such as vegetation cover and spatial heterogeneity. Therefore, the accuracy of the evapotranspiration varied with distance from the flux tower. Overall, the SEBS model showed the highest accuracy for rubber plantations within 1.5 km of the flux tower (RMSE=0.53, RE=18.08%), while it had the lowest accuracy for areas situated 1.0 km from the tower (RMSE=0.65, RE=22.26%). In conclusion, this study would provide a reference for improving the spatiotemporal resolution of evapotranspiration datasets, reveal the seasonal variability and spatial patterns of evapotranspiration in rubber plantations, and contribute to the development of effective water resource management and regulation policies in rubber plantation ecosystems.

Natural rubber is a key and widely used industrial raw material, which is mainly produced from Hevea brasiliensis. Cis-prenyltransferase (CPT) is an important component of natural rubber biosynthesis in laticiferous cells. It has been reported that HbCPT7 and HbCPT8 are specifically and highly expressed in latex, which is the cytoplasm of laticifers, and HblMYB19 and HblMYB44 can significantly promote the expression of HbCPT8 in tobacco and yeast. However, the transcription factors that regulate the specific expression of HbCPT7 in latex are still not clear. Here, we found there are several MYB- and MYC-binding sites located in promoter region of HbCPT7. We totally identified 226 HbMYBs and 19 HbMYCs in Hevea by using a genome-wide scanning approach. The transcriptome data showed that HbMYB1, HbMYB2, HbMYC1, HbMYC2, HbMYC3, HbMYC4 and HbMYC5 were highly expressed in latex. HbMYB1, HbMYB2, HbMYC1, HbMYC4 and HbMYC5 were successfully cloned from the latex of rubber trees. Through yeast one-hybrid assays, it was discovered that HbMYC5 could bind to the promoter regions of 1–1000 bp and 1501–1971 bp upstream of the start codon of HbCPT7. The results would provide a new insight into the molecular mechanism of HbCPT7 in regulating natural rubber biosynthesis.

Thioredoxins play critical roles in the maintenance of cellular redox homeostasis by regulating the structure and function of the target proteins through catalyzing thiol-disulfide exchange reactions. Previous research has confirmed that the y-type thioredoxin HbTRXy2 of rubber tree (Hevea brasiliensis) has a strong antioxidant function. To investigate the molecular mechanism of HbTRXy2 in enhancing antioxidant defense, a yeast two-hybrid library of rubber tree and the bait vector pGBKT7-HbTRXy2 for HbTRXy2 were constructed, and the interacting proteins of HbTRXy2 were identified via yeast two-hybrid in this study. The results indicated that the secondary library constructed in this study had a recombination rate of 100%, an average length of inserted fragments greater than 1000 bp, and a capacity of approximately 3.80×10⁶ CFU/mL. It was identified that the bait vector has no toxicity and self-activating activity in yeast and could be used for yeast two-hybrid screening. After testing, it was found that the bait vector had no toxicity and self-activating activity in yeast and could be used for yeast two-hybrid screening. Using the co-transformation method, 24 proteins interacting with HbTRXy2 were screened from the constructed library. Bioinformatics analysis revealed that the functions of the candidate interacting proteins encompassed redox processes, stress responses, ATP binding and metabolism, Calvin cycle, single-carbon metabolism, carbon fixation, methionine biosynthesis, lipid A biosynthesis, metal ion binding or transport, transmembrane transport, cell volume regulation, phosphate ion homeostasis, protein phosphorylation, protein folding, etc. The results would lay the foundation for further revealing the function and mechanism of HbTRXy2 in rubber tree.

LEC2 is an important member of the LAV subfamily in the plant B3 superfamily and plays a significant regulatory role in embryo development and meristem maintenance. To explore the function of the PvoLEC2 in the cell regeneration of Plukenetia volubilis, the genomic sequence of PvoLEC2 (gPvoLEC2) was cloned through phylogenetic analysis and molecular biology techniques. The function of gPvoLEC2 in promoting plant regeneration was verified in Nicotiana benthamiana, and the function of gPvoLEC2 was studied in P. volubilis hairy roots. Phylogenetic and gene structure analysis indicated that the LEC2-ABI3 subfamily of Euphorbiaceae plants such as P. volubilis, and Arabidopsis thaliana, Oryza sativa, Populus spp. were relatively conserved. Expression analysis showed that PvoLEC2 was only weakly expressed in the late stage of P. volubilis seed development (50-65 DAP), and the motifs and key amino acid sites of the B3 domain were conserved. Overexpression of gPvoLEC2 led to dwarfing of transgenic N. benthamiana plants, difficulty in the growth of the main stem, and abnormal leaf development. At the same time, the regeneration ability of gPvoLEC2 transgenic N. benthamiana organs in vitro was significantly higher than that of the wild type, but lower than that of the positive control-ZmWUS2 & STM transgenic N. benthamiana. Overexpression of gPvoLEC2 in P. volubilis hairy roots led to their shortening and thickening. The results indicate that the genomic sequence of PvoLEC2 is a functional sequence that promotes plant regeneration, but it also causes abnormal development.