Camellia oleifera, a vital woody oil crop in China, has been increasingly threatened by declining soil fertility and frequent disease outbreaks due to improper cultivation practices. Among these, anthracnose is one of the primary diseases limiting yield. To explore environmentally friendly and sustainable control strategies, this study employed biochar as a carrier to deliver Bacillus velezensis SK1-5-2, aiming to evaluate its plant growth-promoting potential and its efficacy in suppressing anthracnose. Pot experiments demonstrated that biochar-loaded SK1-5-2-GFP significantly enhanced C. oleifera growth, improved soil physicochemical properties, and increased disease resistance, indicating a strong synergistic effect. Compared to CK, the biochar-loaded bacterial treatment (BB) significantly improved plant height, leaf area, basal stem diameter, chlorophyll content, and fresh weight. Notably, stem diameter in the BB group increased more substantially than that in the group treated with bacterial suspension alone (BV). Colonization assays revealed that strain SK1-5-2-GFP stably adhered within the porous structure of biochar and efficiently colonized the intercellular spaces in the rhizosphere of C. oleifera, with its viability and functionality unaffected by GFP labeling. Soil properties, total nitrogen, available phosphorus, and organic matter contents in the BB group increased by 55.2%,334.0%, and 181.0%, respectively, compared to CK. Additionally, available potassium in the biochar-only group (BC) increased by 63.1%. Regarding soil enzyme activities, the BB group exhibited significant increases in catalase (28.0%), sucrase (44.4%), urease (57.9%), and acid phosphatase (338.6%) activities compared to CK. Rhizosphere microbial community analysis showed that BB treatment significantly elevated the relative abundance of beneficial microbes, with Bacillus and Priestia emerging as dominant genera. Among fungal communities, the abundance of Talaromyces increased, whereas the pathogenic Fusarium genus obviously declined. The anthracnose incidence in the BB group dropped to 55.6%, markedly lower than that in the BV (60.1%) and BC (77.8%) groups. In conclusion, biochar-loaded B. velezensis enhanced plant growth and disease resistance in C. oleifera by optimizing the rhizosphere microenvironment, modulating microbial community composition, and suppressing phytopathogens. This study would provide a novel microbial regulation strategy for the sustainable cultivation of C. oleifera, offering valuable insights for future applications of agricultural microorganisms and soil improvement technologies.

After intercropping pepper with areca nut, the growth of pepper is restored and the intercropping barrier is alleviated. This is related to the increase in soil microbial diversity by the root exudates of areca nut. However, the specific components that play a role and the effects are still unclear. Three specific components of areca nut root exudates identified were added them to the deionized water for cultivation as the control and the differences in soil microbial carbon source utilization ability among different treatment groups were analyzed using the Biolog microplate method. This was done to clarify the effects of the specific component on the functional diversity and community structure of the rhizosphere soil microorganisms of intercropped pepper and to analyze the correlation between the treatment groups and related indicators using the PCA method. The average absorbance values (AWCD) of the three specific components treatments reached the maximum and were stable significantly higher than those of the deionized water control. The Shannon index and Shannon evenness of the treatments containing flavonoids and phenolic acids were significantly higher than those of the deionized water control, while the Shannon index of the organic acid treatment was only significantly different. The Simpson dominance index of the deionized water control was significantly higher than that of other treatments, while the yellowing acid treatment was significantly lower than that of other treatments. The number of carbon sources changed in the Biolog culture plates caused by the addition of organic acids, phenolic acids, flavonoids and deionized water was 17, 18, 15 and 12 respectively, and the carbon sources decomposed by the three specific component treatments were mainly carbohydrates. With the addition of specific components, the soil microbial community structure also changed significantly. The changes in the yellowing acid treatment were the most obvious, followed by organic acids and phenolic acids, and the soil nutrient indicators also changed with the addition. In summary, the addition of the three specific components of areca nut root exudates significantly enhanced the carbon utilization activity of soil microorganisms in the rhizosphere of intercropped pepper and increased the functional diversity of the soil community. The three treatment groups mainly increased the utilization of carbon sources by microorganisms to enhance diversity and maintained the stability of the community structure, thereby improving the nutrient status of the pepper rhizosphere and alleviating the harm of pepper intercropping barrier.

Moringa oleifera seed oil was extracted using an aqueous enzymatic method following microwave pretreatment of M. oleifera seed power. The antioxidant activity of M. oleifera seed oil was evaluated by its ability to scavenge hydroxyl radical. Single-factor experiments were initially conducted to evaluate the effects of key parameters, raw material particle size, microwave power, and microwave duration. Based on the findings, an orthogonal experimental design was employed to optimize the microwave pretreatment conditions, ultimately determining the most effective pretreatment parameters. The results showed that the optimal microwave pretreatment conditions were raw material crushing particle size of 60 mesh, microwave power of 800 W, and microwave time of 7 min. Under these conditions, the hydroxyl radical (·OH) scavenging rate of the obtained M. oleifera seed oil (at a concentration of 0.5 mg/mL) was 43.98%. Compared to the sample without microwave pretreatment, the antioxidant activity increased by 15.16% (an absolute increase of 5.79%). This demonstrated that microwave pretreatment effectively enhanced the antioxidant capacity of M. oleifera seed oil extracted via the aqueous enzymatic method. The antioxidant activity tests revealed that M. oleifera seed oil extracted using microwave pretreatment combined with the aqueous enzymatic method possessed significant hydroxyl radical (·OH) scavenging ability, with a half inhibitory concentration (IC₅₀) of 0.14 mg/mL. Additionally, the oil showed certain reducing ability toward Fe³⁺. Furthermore, compared to samples without microwave pretreatment, microwave pretreatment increased the acid value, iodine value, and the levels of polyphenols, total flavonoids, squalene, and phytosterols in Moringa oleifera seed oil extracted via the aqueous enzymatic method. Therefore, microwave pretreatment is a suitable pretreatment method for the enzymatic extraction of M. oleifera seed oil. Compared with the conventional aqueous enzymatic method, it can significantly improve the antioxidant activity of M. oleifera seed oil, increase the concentrations of bioactive compounds such as polyphenols, flavonoids, squalene, and plant sterols. However, it also results in higher acid and iodine values, which may slightly compromise the overall quality of the oil. The results of this study could provide technical insights and references for the comprehensive development and high-value utilization of M. oleifera resources.

The growth of fruit trees inevitably casts a certain degree of shade on the grass plants in the orchard. Therefore, the selected grass species usually need to possess a certain level of shade tolerance. This study investigated the shade tolerance of two prevalent ground cover species in southern China, Alysicarpus bupleurifolius (L.) DC. and Alysicarpus vaginalis (L.) DC.. Different shading treatments were set with full light as the control (CK). Growth and physiological indices of the two species were measured, and a comprehensive evaluation of the shade tolerance was conducted to assess the potential as ground cover species in orchards. Findings indicated that as shading intensified, both species exhibited an overall increase in the leaf width, leaf area plant height and the proportion of aboveground biomass, while the stem diameter and total biomass showed a downward trend. Compared with A. vaginalis, the leaf area of A. bupleurifolius increased faster after 21 days of shading treatment, and the total biomass decreased less after 42 days of shading treatment. After shading treatment, the PSII maximum photochemical quantum yield (Fv/Fm) of the two plants was higher than 0.80, and shading did not cause serious damage to the photosynthetic system of the two plants. The relative electrical conductivity and malondialdehyde content of the leaves of the two species generally rose with increased shading intensity, whereas the peroxidase activity (POD) activity under shading conditions displayed distinct patterns. With the increase of shading intensity, the POD activity of A. bupleurifolius increased first and then decreased, while that of A. vaginalis showed a downward trend. Principal Component Analysis (PCA) was performed to reduce the dimensionality of 14 shade tolerance indices into two principal components, which cumulatively accounted for 88.66% of the total variance. In the first principal component (PC1), the contribution rate of malondialdehyde (MDA) content was the highest. In the second principal component (PC2), the contribution rate of leaf relative conductivity was the highest. The results of comprehensive evaluation of shade tolerance by membership function method showed that A. bupleurifolius was higher than that of A. vaginalis under identical shading conditions, indicating that the shade tolerance of A. bupleurifolius was higher than that of A. vaginalis. In summary, both A. bupleurifolius and A. vaginalis exhibit noticeable shade tolerance, with A. bupleurifolius outperforming A. vaginalis, thereby affirming the potential as viable orchard ground cover species.

The axillary buds, which are embedded in the stem of Phalaenopsis and lurked at the base of leaves, can germinate and elongate to form pedicels under suitable conditions. The microscopic observation of the differentiation process is one of the important research contents to understand the flower development process and influencing factors of Phalaenopsis. In order to establish a paraffin section method for two different tissues with soft and hard connection, the stem segment with axillary bud was used as the test material. The preparation steps, such as fixed time, softening liquid concentration and softening time, dehydration, etc., which mainly affect the paraffin section effect, were optimized. The results showed that vacuuming the fixative and extending the fixative time to 48 h or more were conducive to the full penetration of the fixative, and the fixative effect was the best. Using 10%, 12% hydrofluoric acid solution to soften for 12, 15 days and vacuuming for 30 min during softening could greatly reduce the brittleness and hardness of stem tissues with high lignification degree, meet the soft and hard requirements of sections, and effectively solve the problem of tissue separation and fragmentation caused by uneven softening. Dehydration treatment was set up with 7 step by step dehydration gradients from 30% to 100% ethanol, and the gradual replacement steps of anhydrous ethanol to xylene were added, which could avoid the shrinkage and deformation of tissue materials of Phalaenopsis and ensure the integrity of tissue morphology. The optimized preparation method avoids the problems such as incomplete softening, separation of tissues from paraffin wax, crumpling and crushing of wax bands, and cavity of sections caused by conventional preparation of the stem segment of the axillary bud of Phalaenopsis girdle, etc. The overall structure of the obtained sections tends to be complete, the staining is uniform and bright, and the tissue cells in each part are obviously colored. Young bud tissue and lignified stem tissue can be clearly distinguished. In this study, a set of paraffin section preparation method was developed which could be applied to the stem segment of Phalaenopsis axillary bud, a soft and hard tissue material, and would provide a technical basis for further study on the differentiation process of latent axillary bud germination of Phalaenopsis.

Cowpea aphids, two-spotted spider mites, and bean thrips are main pests during the cowpea seedling stage, severely impacting the growth and development of cowpea plants. To evaluate the safety and control efficacy of four seed coating treatments, 10% clothianidin flowable concentrate for seed treatment FS, 30% thiamethoxan FS, 600 g/L imidacloprid flowable concentrate for seed coating FSC and 8% fipronil FSC on three common pests during the cowpea seedling stage, this study conducted indoor pot experiments with insect infestations. The experiments aimed to evaluate the impact of the four seed coatings on cowpea emergence and the effectiveness in controlling cowpea aphids, two-spotted spider mites, and bean thrips. The results indicated that the germination rate of cowpea treated with 10% clothianidin FS, 30% thiamethoxan FS, 600 g/L imidacloprid FSC, and 8% fipronil FSC was 95.83%, 91.67%, 95.83% and 95.83%, respectively. The rate was slightly lower than that of the control (100%), but did not significantly affect crop growth. The findings revealed that 30% thiamethoxan FS exhibited the highest control efficacy against both cowpea aphids and bean thrips. Specifically, the control efficacy against cowpea aphids at 3, 7 and 14 days post-infestation was 65.04%, 81.10% and 72.35%, respectively. For bean thrips, the control efficacy at the same time points was 15.41%, 58.61% and 54.89%, respectively. As the infestation period progressed, the effectiveness of the seed coating treatments in controlling cowpea aphids and bean thrips gradually decreased. None of the four seed coating treatments demonstrated significant control efficacy against two-spotted spider mites. This research provides technical support for pest management during the seedling stage of cowpea production.

Monascus is usually used in food and medical industries. To explore the biocontrol potential of Monascus and its secondary metabolites against plant biocontrol pathogens, in this study, through the isolation and identification of the fungi from humus samples in the rain forest, a total of five strains growing well on the potato dextrose agar medium were screened, the colonies were red, with typical Monascus morphological characteristics. The strains were identified as Monascus sanguineus based on the sequencing and analysis of ITS, LSU and pksKS gene sequences, The results of antagonistic experiments showed that the five strains of Monascus had better and more obvious inhibitory effects on Fusarium oxysporum f. sp. cubense, F. oxysporum f. sp. tracheiphilium, Phytophthora capsici, Colletotrichum gloeosporioides. After fermentation of Monascus with different media, high performance liquid chromatography (HPLC) and nuclear magnetic resonance analysis were carried out. It was found that Monascus could produce abundant secondary metabolites with strong antibacterial activity on solid medium, especially on wheat bran medium. The further pot experiment proved that Monascus could effectively reduce the wilt index of cowpea, and the best biocontrol effect was obtained when the spore concentration was 10⁶ CFU/mL. In summary, Monascus isolated from tropical rain forest showed good results of better biocontrol of plant diseases, and the secondary metabolites obtained by fermentation in rice medium had strong antibacterial activity, and could effectively control cowpea blight. Monascus strains isolated from tropical rain forest have great potential in plant disease biocontrol application, which can provide more abundant strains selection for plant disease biocontrol.

Meloidogyne enterolobii is a pathogen causing significant damages to pepper production. Utilization of resistant cultivars is the most economical and environmentally friendly method to control this disease. A deeper understanding of the regulatory mechanisms of resistance to root-knot nematodes could facilitate the breeding process of disease-resistant cultivars. In previous studies, analysis of transcriptomic data of Hainan local M. enterolobii-resistant pepper germplasm CF25 before and after inoculation were carried out to explore metabolic pathways closely related to nematode resistance. In order to further explore the regulatory mechanisms of resistance, sRNA libraries of CF25 before and after inoculation with M. enterolobii were sequenced to identify a total of 133 differentially expressed miRNAs. Based on the criteria of P≤0.05 and |log₂(FC)|≥3, 33 significantly differentially expressed miRNAs were identified, including 19 known miRNAs and 14 newly discovered miRNAs. Target gene prediction for the 33 miRNAs yielded a total of 373 target genes, with miR5658-z having the highest number of predicted target genes. GO and KEGG analyses showed that the target genes were mainly enriched in pathways related to plant-pathogen interactions and signal transduction. It is speculated that miRNA-mediated signal transduction and plant defense responses might be important reasons for the resistance of CF25 to M. enterolobii. To preliminarily verify the regulatory relationships between differentially expressed miRNA and the target genes, six differentially expressed miRNA and the target genes were selected for qRT-PCR validation. The results showed that the differential expression trends of miRNA and target genes were consistent with the high-throughput sequencing results and generally conformed to the negative regulation pattern between miRNA and the target genes. The results of this study suggest that miRNA may play significant roles in the defense response to root-knot nematodes and lay the foundation for furtherly elucidating the mechanisms of miRNA-mediated nematode resistance in pepper.

Sugarcane (Saccharum hybrids spp.) is an important sugar crop and cash crop in Guangxi. Revealing the characteristics of sugarcane nutrient requirements is an important foundation for promoting high yield, high quality and efficient cultivation of sugarcane. In recent years, the selection and application of new sugarcane varieties in China have been rapid. A field experiment was conducted in the main sugarcane producing areas of Guangxi on red upland soil to promote the efficient cultivation of new sugarcane varieties. The dry matter accumulation, nutrient accumulation, and nutrient efficiency of GT44, GT49, GT55, GT58 and YT00-236 in both plant and ratoon crops were analyzed. The results showed that the dry matter accumulation in the 2^nd ratoon crop of the five varieties was significantly higher than that in the plant and 1^st ratoon crops. The accumulated amount of stalk dry matter and whole crop dry matter in three crops were the highest in GT58, reaching 66 946 kg/hm² and 96 785 kg/hm², respectively, which was 6.48%-19.01% and 2.57%-25.06% more than that in the other varieties, followed by YT 00-236, and the least in GT 49. The accumulation of N, P and K in the 2^nd ratoon crop was significantly higher than that in the plant and 1^st ratoon crops for all the varieties. In different crops, the accumulation of N, P and K in the five varieties was 99.81-212.18, 11.04-27.01, 150.09-400.29 kg/hm², respectively. The accumulated amount of N, P and K in the three crops was the highest in GT58, which increased by 5.16%-20.75%, 4.38%-31.85% and 6.29%-21.45%, respectively, compared with the other varieties, and that in GT49 was the lowest. The N, P, K requirement of a ton cane in different crops for the five varieties was 1.66-2.59, 0.19-0.30 and 2.76-3.76 kg, respectively, but GT44 and GT55 had more requirements while GT49 had less requirements. The economic efficiency of nitrogen, phosphorus and potassium in the three crops was higher in GT49, and the physiological efficiency of nitrogen, phosphorus and potassium was higher in YT00-236. In conclusion, the biological production of GT58 is better, and the nutrient efficiency of GT49 and YT0026 is higher.

An antimicrobial peptide (SAMP) derived from Microcitrus australasica can not only reduce the concentration of Candidatus Liberibacter asiaticus (CLas) in the infected trees and reduce the symptoms of the diseased trees, but also induce innate immunity and prevent the infection of Huanglongbing in healthy trees that are not infected with Huanglongbing. MaSAMP was analyzed by functional structure, subcellular localization and phylogeny. The results showed that the open reading frame (ORF) of MaSAMP was 201 bp in length, encoding 67 amino acids. The molecular weight of the corresponding protein was 7.59959 kDa, the theoretical isoelectric point was 5.38, and the instability index (Instability index (II)) was 33.22. The aliphatic index was 87.16%, and the grand average of hydropathicity was -0.09, indicating that the protein was a hydrophilic one. The protein contained one Dabb domain and was predominantly structured by α-helices and random coils. In terms of evolution, MaSAMP was phylogenetically close to the stress-response A/B barrel domain-containing protein CISIN_1g033887mg from Citrus sinensis and the A/B barrel domain protein HS1 from Citrus×clementina, with protein similarity of 97.01% and 91.04%, respectively. Subcellular localization results indicated that MaSAMP was localized in chloroplasts. Furthermore, through homologous recombination, a pCAMBIA1300-35S::MaSAMP-EGFP overexpression vector fused with an EGFP fluorescent tag was successfully constructed, and transgenic citrus plants were obtained using agrobacterium-mediated in planta transformation technology. This study would provide a material basis for subsequent research on the biological functions of MaSAMP.