This study aimed to study the effects of long-term grass planting on soil fertility, enzyme activity and microbial diversity in tropical latosol soil, providing theoretical and technical support for improving the fertility and amelioration of tropical latosol soil. Using clean tillage as the control and three grass-planting treatments were established: Reyan No. 2 Stylosanthes (Re) and Ubon Stylosanthes (Ub) and natural grass (NG). Soil samples from 0-20 cm and 20-40 cm layers were collected to measure soil organic matter, pH, nitrogen, phosphorus, potassium and related enzyme activities. Utilizing a high-throughput sequencing platform to analyze soil bacterial and fungal communities, and investigating the effects of long-term orchard grass cultivation on the physical and chemical properties, enzyme activity, and microbial diversity of latosol soil. Five years of grass cultivation significantly increased soil organic matter, total nitrogen, and alkali-hydrolyzed nitrogen. with higher levels in Reiyan No. 2 and Ubon treatments compared to natural grass. Natural grass significantly increased total phosphorus in the 0-20 cm layer, while Stylosanthes treatments significantly enhanced total phosphorus in the 20-40 cm layer. Long-term grass planting significantly increased urease, acid phosphatase, and sucrase activities in both soil layers, with no notable effect on catalase activity. The Stylosanthes treatments showed higher urease, acid phosphatase, and sucrase activities than natural grass. Correlation analysis revealed that acid phosphatase, urease, and sucrase were extremely significantly positively correlated with organic matter, total nitrogen and alkali-hydrolyzed nitrogen. Acid phosphatase was significantly positively correlated with pH, while catalase only correlated significantly with organic matter, alkali-hydrolyzed nitrogen. Long-term grass cultivation, particularly the Ubon treatment, increased bacterial OTUs numbers in the 20-40 cm layer. Grass cultivation altered bacterial and fungal community compositions. The dominated bacterial phyla were Acidobacteria, Chloroflexi, Verrucomicrobia and Proteobacteria. In the 0-20 cm layer, grass cultivation increased the relative abundances of Acidobacteria, Verrucomicrobia and Proteobacteria but reduced Chloroflexi. For fungal, Ascomycota, Basidiomycota and Mucoromycota were dominant. Grass cultivation decreased Ascomycota abundance while increasing Mucoromycota. Soil environmental factors significantly influenced microbial communities. Acid phosphatase, organic matter, urease and pH were key drivers of bacterial community changes, whereas organic matter, total nitrogen, alkali-hydrolyzed nitrogen, sucrase and urease primarily shaped fungal community structure. Long-term grass cultivation in orchards, particularly Stylosanthes, significantly increased the organic matter, total nitrogen, and alkali-hydrolyzable nitrogen content in latosol soil. It also enhanced the activities of soil urease, acid phosphatase, and invertase enzymes. Furthermore, it altered the community structure and diversity of both soil bacteria and fungi, thereby effectively improving soil fertility and ameliorating the soil micro-ecological environment.

Pathogenesis-related (PR) proteins are crucial functional proteins in plants responding to stress, exhibiting multiple biological roles in rubber trees (Hevea brasiliensis). This article systematically reviewed recent advances in PR protein research in rubber trees, with emphasis on the functional characteristics in stress resistance mechanisms, laticifer plugging, and allergenicity, while highlighting the critical relationship between PR proteins and laticifer plugging. PR proteins participate in defense responses against stresses through complex molecular networks, potentially influencing latex yield via laticifer plugging processes. Some PR proteins exhibit strong allergenic properties. Although transgenic studies of PR proteins have achieved preliminary progress, further optimization of expression regulation strategies is required to balance stress resistance, yield, and allergenicity. Future research should prioritize elucidating the mechanistic roles of PR proteins, especially investigating how the expression levels of pathogenesis-related proteins (particularly chitinases and β-1,3-glucanases) correlate with rubber productivity. Concurrently, functional exploration of understudied PR protein categories like PR-14 warrants attention. Developing precise molecular breeding technologies based on these findings will provide both theoretical foundations and technical support for rubber tree variety improvement.

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

Carbonic anhydrase (CA) plays an important role in the photosynthesis of plants and response to stress. Cassava CA gene was cloned using the cDNA of SC124 as template. The CDS length of MeCA was 1008 nt, encoding 336 amino acids. The homology was 99.70% between the cloned sequence and Manes.15G167500.1 in the database. The evolutionary tree resulted that MeCA belonged to the same branch as the AtβCA subfamily of Arabidopsis. The sequence similarity between MeCA and AtβCA1 protein reached 73.13% and contained identical motif. MeCA gene expression was the highest in functional leaves, followed in young leaves, significantly higher in fibrous roots and stems, and significantly down-regulated in shading stressed cassava leaves. In addition, the gene showed significant upregulated expression in the initial stage, and then it dropped to the control level when cassava leaves were treated with low temperature. This study created transgenic cassava with overexpression of MeCA gene, and observed that MeCA protein was localized in chloroplasts, and the contents of various chlorophyll were significantly higher in the leaves of transgenic plants than that of control. The results of yeast two-hybrid point-to-point experiments showed that MeCA protein interacted with MeH1.2. The result indicated that MeCA gene could respond to light and low temperature stresses, and maight participate in plant response to stress by affecting plant growth interacting with MeH1.2 proteins. This study would provide a new gene resource for genetic improvement of cassava resistance.

During the biosynthesis process of lignin in plants, cinnamyl alcohol dehydrogenase (CAD) plays a crucial role, catalyzing the final step reaction in the entire metabolic pathway. To explore the potential functions of the CAD gene family in tea plants, CAD gene family members were identified in the genome of Huangyan tea plants and a series of bioinformatics analyses were conducted. Based on transcriptome data, the gene expression of the members in different organs of tea plants and after damage by the Empoasca vitis were studied. A total of 36 members of HD-CsCADs were identified, which were unevenly distributed on 9 chromosomes and encoded amino acid lengths ranging from 300 aa to 621 aa and protein molecular weights ranging from 321.40 kDa to 666.49 kDa. HD-CsCADs had 0 to 3 introns and the promoters containing 79 types of cis-acting elements, among which the number of elements related to stress response was the highest. Combined with the phylogenetic tree, HD-CsCADs could be divided into 4 subfamilies. There were significant differences in the expression levels of HD-CsCADs in different organs of tea plants. HD-CsCAD-15 was highly homologous to CAD genes involved in lignin biosynthesis in other plants and was highly expressed in stem tissues. In addition, the expression of the genes after damage by E. vitis on tea seedlings was analyzed. The expression of HD-CsCAD-11 and HD-CsCAD-15 was relatively obvious and could be used as important CAD genes related to lignin metabolism and tea plant defense against pests. The results would provide theoretical basis for the defense mechanism of tea plants against the small green leaf hopper and the utilization of CAD gene functions.

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

In this study, Cymbopogon winterianus was used as the experimental material, and the DNA sequence of C. winterianus was sequenced using the Illumina NovaSeq 6000 sequencing platform. The sequencing data were assembled with GetOrganelle v1.7.7.0 software to construct the chloroplast genome. Referring to the known chloroplast genome of C. flexuosus, the chloroplast genome of C. winterianus was annotated, and the genomic characteristics were analyzed and a phylogenetic tree was constructed. The chloroplast genome of C. winterianus was 139 823 bp in length, with a typical circular quadripartite structure. The GC content was 38.45%, and the AT content was 61.55%. It included a large single-copy region (LSC) with a length of 82 214 bp, a pair of inverted repeat regions (IR) with a length of 21 368 bp, and a small single-copy region (SSC) of 14 873 bp. A total of 130 genes were annotated in the chloroplast genome of C. winterianus (including 85 mRNA genes, 37 tRNA genes, and 8 rRNA genes). In addition, among the annotated genes, there were 16 double-copy genes, accounting for 12.31%, including 7 tRNA genes, 4 self-replication genes, 4 rRNA genes, 2 protein genes with unknown functions, and 1 NADH dehydrogenase subunit gene. A total of 144 SSR loci were detected in the chloroplast genome of C. winterianus, with mononucleotide repeats being absolutely dominant, mainly A/T. After comparing the boundaries of the inverted repeat sequences of four Cymbopogon species, it was found that C. flexuosus, C. pospischilii, and C. winterianus exhibited extremely high homology in gene structure and species. Among them, the ndhH gene was located in the small single-copy region (SSC), and the ndhF gene was located in the boundary region between the SSC and IRb. However, C. winterianus had an additional rps3 gene in the LSC region compared with C. flexuosus and C. pospischilii. Phylogenetic tree analysis showed that C. winterianus had the closest genetic relationship with C. pospischilii and C. citratus (MK593547.1). This study completed the assembly and annotation of the complete chloroplast genome of C. winterianus, analyzed the characteristics of the chloroplast genome of C. winterianus, and preliminarily explored the phylogenetic position of C. winterianus within the genus Cymbopogon. It would lay a good foundation for the phylogenetic, genetic diversity, and genomic studies of Cymbopogon plants, as well as for the discovery and utilization of important functional genes.

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

Improving and upgrading the efficiency of sugar factories and income of sugarcane farmers are the fundamental goals of the sugarcane industrial development. This study introduced the breeding process of the early-maturing, high-sugar, high-yield, automatic defoliation new sugarcane variety Guitang 76 (GT76) and its production efficiency in different regions, in order to provide planting technical basis for this new sugarcane variety in the coming years. Guitang 76 was selected through the “five nurseries” breeding procedure, and developed based on traits of early maturity, high sugar content and high yield, and also included characteristics of strong perennial roots, high uniformity, tolerance to drought, disease and infertility, and automatic defoliation. Finally, the Guitang 76 production performance was evaluated through the Guangxi new sugarcane variety regional test. The main process was as follows: In April 2010, 220 seedlings were obtained from the combination of CP81-1254×ROC22, planted in the hybrid nursery. In February 2011, five healthy individual plants were selected from the hybrid nursery and planted in the selection nursery. In December 2011, two strains were selected from the selection nursery and entered the identification nursery. In January 2013, one strain was selected from the identification nursery (named Guitang 10-2118), and in February 2013, it entered the preparation variety comparison nursery. After observation and screening, it was selected into the variety comparison nursery in March 2014, and later selected for the 2021—2023 of Guangxi sugarcane new variety regional trials (one year new planted sugarcane and two years perennial sugarcane trials). The results of regional trials showed that the stem diameter of Guitang 10-2118 was between 2.5–3.0 cm, which is a medium-large stem variety, the average number of effective stems was 8140 per hm² more than that of the control variety ROC22. The yield of newly planted sugarcane was 7.72% lower than that of ROC22, but the yield of perennial sugarcane in the first year was 7.28% higher than that of ROC22, and the yield of perennial sugarcane in the second year was 15.24% higher than that of ROC22, and the average yield in three years was higher (5.24%) than that of ROC22. The average sucrose content from November to March was 15.04%, which was 1.32% higher than that of ROC22. Guitang 10-2118 also showed other significant traits including tall plants, long internodes, automatic defoliation, strong perennial roots, wide adaptability, high resistance to smut and tip rot, etc. Guitang 10-2118 was renamed as Guitang 76 (GT76). This article also introduced the key points of cultivation strategies of GT76, providing technical support for its promotion, application and better cane production in coming years.

This study was aimed to identify high-quality and stress-resistant germplasm resources of subtropical tea for the purpose of supporting new variety breeding and the development of characteristic tea products. Leaves from 50 tea accessions cultivated at Tea Teaching and Research Base of Guangxi Vocational and Technical College in Nanning were selected as the samples. 17 leaf anatomical and structural traits were examined to assess the genetic diversity. Based on stress resistance, processing suitability, productivity potential of the traits were evaluated. Principal component analysis combined with hierarchical cluster analysis was employed for the comprehensive evaluation. There existed substantial genetic variation among the accessions, and the coefficient of variation ranged from 11.00% to 39.10%. The accessions demonstrated robust stress resistance with average membership function value for drought resistance and pest resistance 0.67 and 0.61, respectively, along with average cold resistance score 6.28. The average productivity index of 3329.20 suggested a relatively high productivity potential. Based on the leaf anatomical and structural indicators, the accessions were clustered into three distinct groups. The upper cuticle thickness, lower cuticle thickness, upper epidermis thickness, lower epidermis thickness, palisade tissue thickness, palisade tissue layer number, spongy tissue layer thickness, leaf thickness, and calcium oxalate crystal indexes of the Group 2 appeared to be significantly or highly significantly different than those of Group 1 and Group 3. Based on the top five principal component values and the corresponding eigenvalues of the accessions, a linear equation was established to calculate the comprehensive score of the principal components. The top 10 accessions exhibited superior overall characteristics, demonstrating strong potential for breeding elite tea cultivars. These findings would provide valuable references for identification and utilization of the superior local tea germplasm resources in Guangxi.