Phytochelatin synthase (PCS) is a key enzyme that catalyzes the synthesis of phytochelatin (PC). PC can reduce the toxicity of heavy metals to plants through complexation. Heavy metal pollution in soil increases the risk of cassava food safety. It is of great significance to study the reduction and control of heavy metals in cassava by analyzing the function of MePCS1 gene. In this study, the coding region of MePCS1 gene in cassava variety SC8 was cloned by PCR. The full length was 1512 bp, encoding 503 amino acids. Protein sequence analysis showed that MePCS1 protein was a hydrophilic protein, containing 41 phosphorylation sites and 2 glycosylation sites, without signal peptide. The phylogenetic tree showed that the cassava MePCS1 protein had the closest relationship with the PCS protein of the rubber tree. The qPCR analysis showed that the MePCS1 gene had the highest expression level in the stem. During the development of cassava roots, the expression level of MePCS1 gene was the highest in the root enlargement period. Lead (Pb) stress induced MePCS1 gene expression. MePCS1 gene can improve the tolerance of BY4741 yeast to Pb. The results of this study provide new information for further analysis of the functional characteristics of the MePCS1 gene and its mechanism for reducing Pb in cassava tuber roots.

Cassava (Manihot esclenta Crantz) has excellent planting characteristics such as drought resistance, barren tolerance and strong adaptability, and is the main food crop for more than 1 billion people in the world. CMLs (calmodulin-like proteins) are plant calmodulin-like receptors in cells. They interact with other calmodulin-binding proteins to regulate cellular physiological processes and participate in plant stress response. MeCML42 gene in cassava is induced by drought stress. In order to study the drought stress response pathway involved in this gene, yeast two-hybridization was used to screen the interacting proteins of MeCML42. Firstly, the decoy vector pGBKT7-MeCML42 was constructed by homologous recombination technique, and the self-activation experiment showed that MeCML42 protein had no self-activation activity. The toxicity test showed that MeCML42 protein was not toxic to yeast and did not affect the normal growth of yeast. The cDNA library was screened by yeast two-hybridization and 7 candidate interacting proteins were obtained. The interaction between MeCML42 and thioredoxin MeCDSP32 was verified by yeast double heterogyclic experiment. Mannitol simulation of drought stress showed that the expressions of MeCML42 and MeCDSP32 were both induced by drought, and the expression levels were the highest at 48 h under stress. These results indicated that MeCML42 and MeCDSP32 were synergistically involved in cassava's response to drought stress. The results of this study provide a new basis for MeCML42 to participate in cassava response to drought stress.

The level of cyanogenic glucosides content is an important trait for the edible quality of cassava, and Me-CYP79D2 is one of the key enzyme genes regulating cassava cyanogenic glucosides synthesis. This study used the edible variety SC9 as the material, cloned the MeCYP79D2 gene in the cytochrome P450 enzyme family of cassava, analyzed it using bioinformatics software, and detected its expression characteristics in different cassava germplasm tubers using real-time quantitative PCR. The cyanogenic glucosides content was measured using HPLC, and its correlation with the expression level of MeCYP79D2 gene was analyzed. The results showed that the length of the coding region sequence of MeCYP79D2 gene was 1625 bp, encoding 528 amino acids. It belonged to an unstable lipophilic hydrophilic protein with 38 phosphorylation sites. Sequence alignment indicated that the gene was highly conserved, and phylogenetic analysis showed that MeCYP79D2 was closely related to rubber and leprosy trees. There was a significant positive correlation between the expression of MeCYPD2 gene and the content of cyanogen glycosides in cassava roots of germplasms with different levels of cyanogen glycosides. After treatment with methyl jasmonate, the expression of MeCYP79D2 gene in roots was significantly upregulated and the content of cyanogenic glucosides was significantly increased. The results of this study indicates that MeCYP79D2 is involved in cyanogenic glucosides synthesis, providing a theoretical basis for studying the molecular mechanism of cassava cyanogenic glucosides biosynthesis.

The triose-phosphate/phosphate translocator (triose-phosphate/phosphate translocator, TPT) is a triose phosphate transporter that plays an important role in plant carbon metabolism pathways as well as abiotic stresses. Sucrose has a wide range of edible value and important economic value. Sugarcane is the main raw material for sugar production, and sucrose from sugarcane accounts for more than 80% of China's sugar production, so it is very important to achieve the goal of high yield and high resistance of sugarcane. In this study, the sugarcane variety ROC22 was used as the material to clone the sugarcane triose/phosphate transporter gene ShTPT, and the physicochemical properties, conserved domains, transmembrane structure prediction and protein sequence comparison of ShTPT were carried out by bioinformatics methods. The results showed that the CDS of ShTPT was 1221 bp, encoding 406 amino acids, the molecular weight of the protein was 43.63 kDa, and the isoelectric point (pI) was 9.80. It was rich in alanine and leucine, its instability coefficient was 42.51, and its hydrophilic coefficient was 0.583, which was an unstable hydrophobic protein. ShTPT did not contain signal peptides but had 9 transmembrane domains. Conserved domain prediction showed that ShTPT contained a tpt domain, which was consistent with the characteristics of the TPT family. The results of phylogenetic analysis showed that ShTPT was clustered with Sorghum bicolor SbTPT (XP_002454867.1) and Zea mays ZmTPT (NP_001105497.1) with homology of 97.04% and 94.13%, respectively. Further subcellular localization analysis of ShTPT showed that ShTPT was localized in chloroplasts. Tissue expression pattern analysis of sugarcane showed that ShTPT was mainly expressed in leaves, and the expression level in roots and stems was very low. Under the drought stress conditions simulated by PEG, the expression of ShTPT showed an upward trend, indicating that it responded to drought stress. The results of this study suggest that ShTPT is a chloroplast-localized transmembrane transporter, which may be involved in the transport of primary carbon metabolic compounds in sugarcane leaves and responsive to drought stress. This study preliminarily determined that ShTPT gene plays an important role in the transport of carbon assimilates in leaves and abiotic stress, which provides a theoretical basis for further study of its function.

Pineapple, an important tropical fruit, belongs to the family Bromeliaceae (Ananas Merr.), and its flower and fruit development theory and transcriptional regulation technology are one of the hot spots in the pineapple industry. Ethylene is one of the important hormones that regulate the flowering and fruit development of pineapple. In the study of watercore disorder in Bali pineapple varieties, it was found that two MYB transcription factors, AcMYB68 and Ac-MYB109, played an important role in fruit development. With the completion of pineapple genome sequencing, 94 pineapple R2R3-MYB transcription factors have been identified in the pineapple genome, which are divided into 26 subfamilies, and are differentially expressed by salt and other stresses and ABA hormones. In this study we proposed a scientific hypothesis that ethylene mediated MYB transcription factors to regulate the development of pineapple fruits. In order to elucidate the molecular regulatory mechanism, a MYB transcription factor AcMYB103 was cloned from the fruit of pineapple Tainong 17, with a total length of 1204 bp, a coding region of 1038 bp, and encoding 345 amino acids. The protein contains two typical SANT domains, localized to the nucleus, without transmembrane domain and signal peptide, and was a member of the plant R2R3 MYB transcription factor family. Cluster analysis of pineapple and Arabidopsis MYB family members showed that AcMYB103 had the highest similarity with Arabidopsis AtMYB80, At-MYB103 and AtMYB35, and belonged to the S19 subfamily. Furthermore, four ethephon concentrations (volume fraction) of 0%, 0.5%, 1.0% and 1.5% were used to treat the fruits at the small fruit stage, expansion stage and ripe stage of the three cultivars Tainong 17, Xiaomushousi and Damushousi, and the expression level of AcMYB103 was analyzed. The results showed that with the increase of ethephon concentration at the small fruit stage, the expression of AcMYB103 in Tainong 17 showed a down-regulated pattern, and upregulated in the Xiaomushousi and Damushousi mode. In the expansion stage, the downward adjustment pattern was shown in the Tainong 17 and Xiaomushousi varieties, and the upward pattern was shown in the fruit of Damushousi. AcMYB103 was not expressed in fruits at the ripening stage, indicating that the expression of AcMYB103 gene was specific in ethephon-treated varieties and fruit development periods, and played a differentiated regulatory role in the early stage of fruit development. This study would lay a foundation for in-depth study of the mechanism of AcMYB103 gene in the regulation of growth and development of pineapple fruit.

Pineapple is prone to intern browning during storage at room temperature. Diseased and healthy parts of pineapple at early stage of intern browning were used to explore the mechanism of the disease. Three samples from each part were used for transcriptome RNA-Seq analysis. GO, KEGG, cluster analysis of gene expression in various metabolic pathways, and RT-qPCR validation on differential genes were performed and the differential gene expression levels between the diseased (IB) and healthy (WT) parts were compared. IB vs WT had 1037 differentially expressed genes, of which 886 were up-regulated and 130 were down-regulated. GO and KEGG analysis found that the differentially expressed genes in amino acid biosynthesis were the most significant, and the proportion of differentially expressed genes was large. Cluster analysis and RT-qPCR validation found that the sugar metabolism pathway significantly up-regulated the expression levels of related enzyme genes in glycolysis, tricarboxylic acid cycle (TCA), and oxidative phosphorylation processes after fruit disease onset. The response of plants to external environmental signaling pathways revealed a significant down-regulation of resistance enzyme gene expression, a significant up-regulation of pathogenic protein gene expression, and a significant down-regulation of resistance protein gene expression. The antioxidant pathway revealed significant down-regulation of glutathione synthesis gene expression, significant up-regulation of flavonoid biosynthesis related gene expression, significant down-regulation of L-ascorbate peroxidase (APX) gene expression, and significant up-regulation of L-ascorbate oxidase (AOX) homologous gene expression. RNA-Seq and RT-qPCR analysis indicated that pineapple tissue significantly up-regulated key genes in sugar metabolism to accelerate sugar metabolism in fruit disease part, significantly up-regulated key genes in the MAPK signaling pathway, and significantly down-regulated metabolic pathway changes such as antioxidant substances, leading to pineapple intern browning. The results could enrich the gene network of pineapple intern browning and provide a valuable reference for the subsequent gene screening of pineapple intern browning.

Chalcone synthase is a crucial enzyme in the initial stage of the flavonoid biosynthetic pathway. To explore the biological functions of our previously identified chalcone synthase coding gene DlCHS9 from longan, which is associated with anthocyanin accumulation, DlCHS9-SX and DlCHS9-HP from Shixia and Hongpi longan, were cloned respectively. Amino acid sequences of DlCHS9-SX and DlCHS9-HP were compared and found to differ only at position 328, which was not a key active site. Subsequently, an expression vector was created, and the Agrobacterium-mediated leaf disc method was used to introduce DlCHS9-SX into wild tobacco. The anthocyanin content in the petals of transgenic tobacco was notably higher than that in the wild type, suggesting that the DlCHS9-SX gene enhances anthocyanin accumulation in tobacco petals. The promoter sequences of the two DlCHS9 genes revealed a similarity of 96.2%. Compared to the promoter of DlCHS9-HP, the promoter of DlCHS9-SX had 32 SNPs, 14 base insertions, and 12 base deletions. Specifically, the DlCHS9-SX promoter contained an additional abscisic acid responsive element (ABRE), one fewer light-responsive element (Box4), one less low temperature-responsive element (LTR), and one less MYC transcription factor binding site. In conclusion, DlCHS9-SX plays a pivotal role as a structural gene in longan anthocyanin biosynthesis. The differences in the DlCHS9 promoter in Shixia longan may contribute to its lower expression level.

Cold resistance and high-yielding are always the core breeding objectives of Yunnan rubber tree planting area in China. The superior clone was selected by artificial hybridization, and was systematically identified by nursery trial, advanced clonal trial and resistance test. The results showed that Yunyan 80-1983 was a fast-growing, high-yielding and early-maturing rubber tree clone which could be tapped 0.5-1 years earlier. In advanced clonal trials, the girth reached 52.7 cm in the seventh year, which was 122.6% of the control RRIM600 (43.0 cm). The dry rubber yield of 1-13 tapping year was 4.3 kg per tree and 1622.7 kg/hm², which was 130.3% and 122.5% of the control RRIM600 (3.3 kg per tree,1324.8 kg/hm²). The cold resistance was basically equivalent to that of RRIM600, lower than that of GT1 and Yunyan 77-4. It is recommended to be planted in the low-altitude and slight cold damage zone in Yunnan. This clone would provide variety support for optimizing the variety structure, increasing the yield and output value in Yunnan and other rubber planting areas.

The introduction and evaluation of foreign clones play an important role in promoting the development of rubber trees in China. In order to evaluate the adaptability of Indonesian rubber tree clone Reshi 11-107, the stem circumference growth, dry rubber yield, rubber production and discharge characteristics, and natural rubber quality were examined in the clone trail test, which was arranged according to the breeding technical regulations. The average annual stem girth of Reshi 11-107 increased by 7.6 cm before tapping, and increased by 3.0 cm after tapping, and the fast-growing characteristics were obvious. The average yield was 58.41 g and the dry gum content was 33.37% in the first 5 tapping years, which were significantly better than that of the control clone RRIM600. Reshi 11-107 has a large number of laticifers in the bark, the initial flow rate of rubber discharge is fast, the plug index is low, the thiol content is significantly higher than that of the control, and the sucrose content is equivalent to that of the control. It has good characteristics of rubber production and discharge, better potential for rubber production, and good adaptability to cold damage. Reshi 11-107 natural rubber has large molecular weight, high ash content, high initial plasticity value, high tensile strength, high tear strength and good physical and mechanical properties. In conclusion, the comprehensive characters of Reshi 11-107 are better, which could adapt to the planting environment in China, and could be expanded in the type I planting area.

Sugarcane mosaic disease is one of the main viral diseases threatening the production of sugarcane. Sugarcane streak mosaic virus (SCSMV), Sorghum mosaic virus (SrMV) and Sugarcane mosaic virus (SCMV) are the main pathogens. The occurrence of sugarcane mosaic disease seriously affects the quality and yield of sugarcane. The most economical and effective way to control the disease is the application of resistant varieties. In this paper, the damage and controlling ways of sugarcane mosaic disease were summarized. The recent research progress on identification of resistance germplasm resources, resistance inheritance, molecular markers, mining and application of the resistance gene, and breeding of disease-resistant varieties were reviewed. Moreover, the problems existing in sugarcane disease resistance breeding were pointed out, and some suggestions were put forward to strengthen the research on sugarcane mosaic disease resistance breeding.

Sugarcane pokkah boeng disease (PBD) is a major disease of sugarcane in China, which severely affects the yield of sugarcane and causes significant economic losses. Selection and cultivation of PBD resistant sugarcane germplasms is the most economical and effective control method. In this study, a three-year field experiment was conducted in Dingdang of Guangxi, and Dehong of Yunnan to analyze the natural disease data of sugarcane PBD from 2015 to 2017. The objective was to evaluate the disease resistance of 98 sugarcane germplasms in China and provide a reference for breeding disease-resistant sugarcane. The results indicated significant difference between different regions, with the average incidence and disease index higher in Dingdang than Dehong. Joint analysis of variance (ANOVA) showed that germplasms, year, location, month, germplasms×year, germplasms×location and location×month had a significant impact on the incidence and disease index of tip rot (P<0.001). Among them, genotype and year had the greatest impact, indicating that PBD is mainly controlled by genetic and environmental factors. A comparison of meteorological conditions at various locations revealed a positive correlation trend between the PBD occurrence, air temperature, and annual rainfall. The 98 sugarcane germplasms were categorized into five groups, out of which 16 (16.33%) were highly resistant, 32 (32.65%) were resistant, 18 (18.37%) were moderately susceptible, 24 (24.49%) were susceptible, and 8 (8.16%) were highly susceptible. Highly resistant germplasms such as CP94-1100, Q202, ROC21, ROC23, Yuetang 93-159, Guitang 02-1247, Guitang 02-208, Guitang 02-761, Guitang 03-1403, Yuegan 16, Guitang 05-3846, Guitang 05-827, ROC22, Yuetang 00-236, Yuetang 89-240, and Yuetang 94-128 are recommended as the parents for disease resistance breeding. Conversely, highly susceptibility germplasms such as CP72-2086, PINDAR, ROC26, Guitang 02-619, Guitang 05-2743, Guitang 05-322, Liucheng 03-182, and Shuidian 25, should be used with caution. This study distinguished germplasms with stable resistance in different environments, which is significant for germplasm utilization and the breeding of resistant germplasms.

Cassava variety Nanzhi 199 (sweet cassava variety, with erect, compact plant shape and generally unbranched at the top) and chili pepper variety Xiangyan 55 (medium maturity small cowpea variety, with good growth and strong adaptability) were used to study the effects of cassava-pepper intercropping pattern on cassava growth, photosynthetic performance, soil enzyme activity, tuber yield and quality. Three different planting densities of chili peppers in chili peppers and cassava intercropping (T₁, T₂ and T₃, with the spacing of 0.4 m, 0.5 m and 0.6 m, respectively) were designed. The results showed that the aboveground growth indexes of cassava under intercropping treatment had different degrees of inhibition in various growth periods of cassava, and the inhibitory effect deepened with the increase of density and time, so the aboveground plant height and stem thickness of T₃ treatment were minimally inhibited; intercropping treatments were able to improve the relative chlorophyll content of cassava seedling leaves, and the intercropping treatments were able to increase the net photosynthetic rate of the whole period of potato production, stomatal conductance, and the cytosolic rate of the tuber expansion period, and intercellular carbon dioxide concentration during tuber expansion, but had no significant effect on the transpiration rate of cassava in all growth periods; intercropping treatments significantly increased the activities of soil urease, acid phosphatase, catalase and sucrase compared with CK, and the activities of the soil enzymes were significantly higher than those of other intercropping treatments by T₃ except for the activity of soil catalase which had no significant difference among the intercropping treatments; intercropping reduced the aboveground biomass and belowground biomass, and the activity of soil enzymes by T₃; intercropping reduced the relative chlorophyll content of cassava leaves at seedling stage. Although intercropping reduced the above-ground biomass and the number of cassava tubers in the below-ground part, it could improve the weight of cassava, and there was no significant difference between intercropping T₁ and T₂ treatments and the yield of CK, while the acreage yield of T₃ was significantly increased by 13.98%; intercropping could effectively improve the quality of tubers, and the contents of various qualities other than soluble sugar and cellulose in T₃ treatment were significantly higher than that of other treatments, among which, the intercropping treatments were able to increase the starch content of cassava tubers to different degrees, respectively, and increased the starch content of cassava tubers to different degrees. Among them, intercropping treatments were able to increase the starch content of cassava tubers to different degrees, which was increased by 13.06%, 8.25% and 19.33% respectively. In summary, cassava intercropping can improve the yield and quality of cassava tubers by increasing the photosynthetic rate and soil enzyme activity of cassava, and then increase the economic benefits of cassava. Finally, the T₃ treatment with 2 rows of cassava and 2 rows of chili peppers (plant spacing 0.6 m) had the optimal cultivation density, which was a suitable cassava-chili pepper intercropping pattern for Hunan production area.

In view of the deficiency of calcium (Ca), magnesium (Mg), zinc (Zn) and boron (B) in the production of macadamia in Yunnan province, the accumulation characteristics of Ca, Mg, Zn and B in litter, pruned branch and nuts harvest were analyzed to provide a theoretical basis for the optimal management of Ca, Mg, Zn and B nutrients and help the quality and efficiency production of macadamia. In 2021 and 2022, high-yielding trees of macadamia nut variety A16 were used as the test materials to study the quality of dry matter, the content of Ca, Mg, Zn and B nutrients and their cumulative distribution during litter, pruned branch and nuts harvest. The average dry matter weight of litter, pruned branch and nuts harvest of macadamia t was 35.77 kg/plant, among which litter, pruned branch and nuts harvest accounted for 19%, 32% and 49% of the total dry matter weight, respectively. There were significant differences in the content of Ca, Mg, Zn and B nutrients in different tissues, and the overall performance was Ca>Mg>B>Zn. The average cumulative amounts of Ca, Mg, Zn and B in 2 years was 126.13, 23.39, 0.25 g/plant and 0.89 g/plant, respectively. The cumulative distribution of Ca and Mg in litter, pruned branch and nuts harvest was 45%, 48% and 7%, and 26%, 33% and 41%, respectively. The cumulative distribution of Zn was 25%, 28% and 47%, and the cumulative distribution of B was 44%, 36% and 20%, respectively. Among them, leaves (senescent leaves and pruning leaves) were the main accumulation and distribution parts of Ca and B, while pruning leaves and nuts were the main accumulation and distribution parts of Mg and Zn. The estimated apparent nutrient balance indicated that the total nutrient taken by Ca, Mg, Zn and B was 45.41, 8.42, 0.09 kg/hm² and 0.32 kg/hm². After removing some nutrients returned by litter, in the absence of exogenous Ca and Mg input and the input of Zn and B 0.08 kg/hm², Ca, Mg and B nutrients were deficient in macadamia. The results would provide the basis for nutrient optimization management of macadamia.

To clarify the impact of sod-cultural practices on the soil physico-chemical properties in Macadamia orchards, suitable local grass cultivation models were selected. Five common grass species in orchards (Vicia villosa, Trifolium repens, Lolium multiflorum, Vulpia myuros, and Raphanus sativus) were selected in the study with clear tillage as the control to analyze the differences in soil moisture content, temperature, physical properties, nutrients, and fertility among different treatments in orchards. The membership function method was used for comprehensive evaluation. Sod-cultural practices could effectively increase the surface soil moisture content, which was 8.7%~24.0% higher than that of the clear tillage control. Meanwhile, sod-cultural practices could reduce the surface soil temperature of orchards by 7.6% to 16.8%. Compared with tillage, the average soil bulk density in the sod-cultural practice areas decreased by 11.7%. In terms of soil nutrients, sod-cultural practice areas significantly increased the soil organic matter content, with T. repens having the highest soil organic matter content, reaching 32.0 g/kg. Leguminous and cruciferous grass species could significantly increase the soil available nutrient content, while poaceae grass species showed no significant improvement. The soil comprehensive fertility coefficient of the cultivation modes of V. villosa, T. repens, and R. sativus showed the best performance, increased by 51.5%, 49.2%, and 45.4% respectively compared to the clear tillage control. The evaluation of orchard soil fertility could reach a fertile level. The optimal grass cultivation mode obtained using the membership function method was V. villosa. Comprehensive evaluation of the four physical and chemical indicators of soil moisture content, bulk density, temperature, and fertility in each treated orchard by the membership function method revealed the cultivation mode of V. villosa performed the best.

Gibberellic acid is a typical plant growth regulator, which has the efficacy of increasing yield and fruit preservation for crops. The preparation process of gibberellic acid dry flowable is still lacking systematic exploration, and the fruit preservation test of this preparation on citrus still needs to be verified. The study was aimed to investigate the effect of the wet grinding process of sand mill on the performance of gibberellic acid suspension slurry and to determine the performance of dry flowable prepared by spray drying. The 3% gibberellic acid dry flowable was prepared by the wet sand mill and pressure spray drying equipment, and the final process was screened according to the determination of particle size, viscosity, the retention rate of gibberellic acid content, and other performance indexes of the suspension concentrate through the optimization of the number of wet grinding times, the wet grinding speed, and the size of the diameter of zirconia beads used for wet grinding. The effect of 3% gibberellic acid dry flowable on citrus fruit set, fruit thickness, single fruit weight and soluble solids were tested in field efficacy test. The results showed that the optimal grinding process was 1 mm in diameter of the zirconium beads used for grinding, the grinding speed was 2500 r/min and grould twice. The viscosity of the suspension concentrate before spraying was lower than 200 mPa/s, and the particle size was about 2 µm, and the particle size of the suspension concentrate after spraying was about 3 µm after rehydration, and the retention rate of gibberellic acid was more than 90% after this grinding process, and the low viscosity of the slurry could meet the production requirements. The 3% gibberellic acid dry flowable produced by this process has high suspension rate (>90%), fast wetting speed (10 s), high retention rate of gibberellic acid, and the performance indexes are in accordance with the regulations, and there is no precipitation of suspension slurry during the production process. The results of the field trial showed that the spraying of gibberellic acid dry flowable increased the transverse and longitudinal diameter of the citrus single fruit, the thickness of the peel decreased, the weight of the single fruit increased, the soluble solids increased, and the fruiting rate of the planting area increased. The results provide theoretical support for the industrial production of gibberellic acid dry flowable, and the field trial of gibberellic acid dry flowable prepared in this study in citrus trees can provide reference for the application of gibberellic acid in citrus fruit trees.

Xyleborus affinis, a main pest of rubber trees, is effectively monitored and controlled using semiochemicals, a key method in rubber pest management. Chemosensory proteins (CSPs) are believed to play an important role in the process of binding and transporting odorants in insect. To elucidate the role of chemosensory proteins in semiochemicals recognizing by X. affinis, the XaffCSP1~XaffCSP5 genes were cloned and identified in this study. The characteristics of nucleotide and deduced amino acid sequences of the genes were analyzed using bioinformatics methods. The binding mode and ability with 15 different ligands (14 host plant volatiles and 1 aggregation pheromone) was analyzed using molecular docking technology. Results revealed that the length of the open reading frame (ORF) of the five XaffCSPs genes was 366-417 bp, encoding 121-138 amino acids. The predicted protein molecular weight was 13.95-16.08 kDa and all five XaffCSPs contained signal peptide composed of 17-20 amino acid residues at N-terminal. The secondary structure of the proteins was mainly composed of α-helix. All five XaffCSPs possessed four conserved cysteine residues, conforming to the typical characteristics of insect chemosensory proteins. Phylogenetic tree anaylsis indicated that except for XaffCSP5, XaffCSP1 to XaffCSP4 were clustered with CSPs of other bark beetle species. The three-dimensional models of the the five XaffCSPs were with good model quality according to model assessment results, and the models of the five XaffCSPs were composed of six α-helices. Molecular docking results demonstrated all five XaffCSPs had a strong binding affinity with (-)-α-copaene and (+)-longifolene. Additionally, XaffCSP4 showed strong binding to terpinolene and limonene, while XaffCSP5 showed strong binding to camphene, α-pinene, and β-pinene. The binding ability of the five XaffCSPs to (S)-cis-verbenol was relatively weak. The results demonstrated that the five XaffCSPs had good affinity with host volatiles and may be participated in the process of recognizing host plant volatiles by X. affinis. This study would provide a theoretical basis for elucidating the molecular mechanism of X. affinis in recognizing semiochemicals and is of great significance for the control of X. affinis.

The study was aimed to provide technical support for risk management, risk analysis and risk assessment of pests carried by banana seedlings in China. By consulting domestic and foreign literature (mainly including China’s National Pest Quarantine Information System, etc.), a total of 68 species of pests that may be transmitted to bananas exported to China were identified, including 32 species of insects, 19 species of fungi, 9 species of nematodes, 4 species of bacteria, 1 species of mollusca, and 3 species of mites (including spiders). Based on the distribution in China (undistributed or not widely distributed), whether they are officially controlled, and the possibility of being carried with banana seedlings, 9 potential quarantine pests were identified that require further evaluation, including 7 species of fungi and 2 species of bacteria. The 9 potential quarantine pests were qualitatively and quantitatively analyzed one by one in terms of entry, colonization, diffusion possibility, economic impact and multi-index comprehensive evaluation, and 5 species of medium-risk pests and 4 species of high-risk pests were identified. Finally, it was determined that the nine pests including Botryotinia fuckeliana were quarantine pests that require attention when banana seedlings were exported to China, and the corresponding risk management measures were put forward.

Plant protection unmanned aerial vehicle (UAVs) operational parameters have remarkable effects on droplet distribution in UAVs spraying, which significantly affects pesticide utilization rate and treatment effectiveness. The study was aimed to explore the effects of operating parameters of electric UAVs on droplet deposition distribution in mango trees canopy and to enhance the efficiency of targeted deposition by UAVs. The DJI T40 multi-rotor electric plant protection UAV was used and the main operational parameters including droplet sizes (80, 100, 120 μm), flight height (2.0, 2.5, 3.0 m) and flight speed (3.0, 4.0, 5.0 m/s) were optimized by an orthogonal test. When the droplet size was 80 μm with 2.0 m of flight height and 3.0 m/s of flight speed, the droplet deposition density, coverage rate and uniformity in each canopy of mango trees were significantly larger than those of the other groups. There was a negative correlation between droplet deposition density, coverage rate and flight height, flight speed. The results of range analysis showed that droplet size was the main factor affecting the deposition density of droplet in mango canopy. The flight height was the main factor affecting the coverage rate of spray droplets on the front side of the lower canopy leaves and the back side of the inner canopy leaves of mango trees. The flight speed was the main factor affecting the coverage rate of spray droplets on the back side of the upper canopy leaves of mango trees. The spray diameter of the front and back of the leaves of the other layers was the main factor affecting the droplet coverage rate. The droplet distribution within mango canopy exhibited significant variation, with droplet size being the primary factor determining uniformity, followed by flight speed and flight height. In our current study, according to the droplet deposition density, coverage rate and uniformity in mango canopy, the best operating parameters of T40 multi-rotor electric plant protection UAV were obtained as follows: droplet size of 80 μm, operation height of 2.0 m, and operation speed of 3.0 m/s. It could provide fundamental guidance of the operation of small UAVs for the aerial spraying of mango trees and other similar orchards.

Meloidogyne enterolobii is one of the most devastating pathogens in tomato (Solanum lycopersicum) production. Grafting with resistant rootstocks could help superior cultivars gain root-knot nematode resistance straightly. Previously, we identified a medium-resistant tomato rootstock cultivar Guizhen 1. In order to deepen the understanding to its resistance mechanism, we inoculated Guizhen 1 and susceptible cultivar Yala with M. enterolobii, and measured the proportion of root knots and nematode numbers in roots once every four days within 28 days. The root knot proportion of Yala reached 71.7%, which was kept under 36.0% in Guizhen 1. The root knot proportions between resistant and susceptible cultivars were significantly different on day 12, 16, 20, 24 and 28 after inoculation. Whereas the differences of nematode numbers between resistant and susceptible cultivars were not significant except on day 20. Thus it can be seen that the resistance of Guizhen 1 was not reflected by limiting the invasion of nematodes. The LC-MS based non-targeted metabolome of resistant and susceptible roots on 5th day after inoculation were measured. With the threshold of VIP>1 and P<0.05, 415 significantly different metabolites were gained, among which 280 were up-regulated and 135 were down-regulated. The top 8 classes of metabolites with largest number of metabolites were amino acid and its metabolites, heterocyclic compounds, benzene and its derivatives, organic acid and its derivatives, aldehyde, ketone and ester, fatty acyls, glycerol phospholipids, alcohol and amines. KEGG dataset were employed to do the metabolite pathway enrichment analysis. Glycerophospholipid metabolism, ascorbate and aldarate metabolism, nicotinate and nicotinamide metabolism, betalain biosynthesis and flavonoid biosynthesis pathways had relatively high level of enrichment, with the glycerophospholipid metabolism having the highest enrichment level. In glycerophospholipid metabolism pathway, there were several metabolites with significant differences between resistant and susceptible cultivars, which were phosphocholine, phosphatidylcholine, lysophosphatidylcholine, sn-glycero-3-phosphocholine, triethanolamine and diethanolamine. It was speculated that glycerophospholipid metabolism pathway might enhance the M. enterolobii resistance of Guizhen 1 at certain level. In this study, the histological and metabolomic fundamentals of M. enterolobii resistance were explored in tomato rootstock cultivar Guizhen 1, which would provide certain basis for the in-depth study on resistance mechanism in the future.

The purpose of the study was to explore the relationship between Lvnonglin^® 41 compound microbial fertilizer (LNL41) and the occurrence of tomato Fusarium wilt and soil fungal communities and to provide theoretical basis for the prevention and control of tomato Fusarium wilt and the rational application of nitrogen fertilizers. Using plots with severe occurrence of tomato Fusarium wilt in previous years as experimental plots, four treatments were designed in field: water control (CK), LNL41, bacterial fertilizer nutrient substrate (NS), compound microbial (CM). The effects of different treatments on the concentrations of main soil nutrients of rhizosphere soil, plant growth, soil respiration rate, incidence of Fusarium wit disease were analyzed. Using 18S rDNA sequencing technology, the differences in the occurrence of tomato Fusarium wilt and the fungal community structure in rhizosphere soil under LNL41 were investigated. Compared with other treatments, the LNL41 treatment is the best. The treatments with LNL41 and CM had higher contents of organic matter and available phosphorus in tomato rhizosphere soil than other two treatments. Compared with the control, the plant height, stem circumference, leaf area, photosynthesis, chlorophyll, yield and water-soluble sugar treated by LNL41, CM and NS all increased by 8.87%-34.71%, 15.93%-67.62%, 13.37%-52.88%,3.17%-12.55%, 3.20%-20.49%, 4.38%-19.53%, 0.46%-8.79% respectively. The soil respiration rate increased by 59.52% in LNL41. The incidence and control effect of tomato Fusarium wilt disease in different growth stages reached 2.33%-16.33% and 80.50%-90.83% in LNL41, respectively. The Ace index and Chao1 index at the fungal genus level in the rhizosphere soil increased by 26.97%-57.71% and 24.89%-56.00%, respectively. The diversity indicators of the Simpson index and Shannon index of the CM treatment increased by 25.75%-29.45% and 39.04%-49.13%, while the diversity indicators of the NS treatment decreased. Hypocreaceae and Trichoderma treated with LNL41 were among the top five dominant families and genera (both abundances were 8.56%); Trichoderma was similar to Cladosporium, Uwebraunia, Aureobasidium and Fusarium in the four treatments, and was positively correlated with Aspergillus, Uwebraunia and Alternaria respectively. Chao1 index treated with LNL41 was significantly positively correlated with organic matter, available phosphorus, available potassium and soil respiration rate, and was significantly negatively correlated with salinity and disease incidence. The abundance of saprophytic functional groups treated with microbial fertilizer increased by 0.92-11.15 percentage, plant pathogen decreased by 2.55 percentage, and endophyte decreased by 7.95 percentage, while only two functional groups treated with NS and CM increased in abundance. LNL41 can significantly improve the ratio of soil nutrients, thereby improving the structure and functional characteristics of soil fungal communities, stimulating saprophytic functions of the fungal communities, promoting tomato growth, and reducing the rate of blight.

UV-C treatment is an emerging and abiotic stress technology, and is a non-ionizing and non-thermal physi-caltechnology. By using proper dose of UV-C treatment, it can be used to inactivate microbes on the surfaces of food, reduce the decay rate, maintain phytonutrients content and organoleptic quality. According to the research, the application of UV-C treatment is effective in increasing the levels of antioxidants content and the antioxidant capacity of fruits, then it can enhance resistance ability of some fruits, and which makes storage qualities better and extend the shelf life. Combining UV-C treatment with other technologies, such as 1-methylcyclopropene (1-MCP), and coating with all kinds of active compositions, and different packaging so on, it can form a hurdle technique which is a combination by two or more treatment, it can result in synergistic or additive interactions when compared to any single preservation technique in some horticulture. In addition, UV-C treatment is an eco-friendly and a cost effective technology which can be carried out easily without complex equipment on post-harvest and logistics and transportation for their commercialization. This critical review aims to summarize the research conducted on the effects of UV-C treatment on postharvest fruits in the past five years, the review draws the current challenges as well as future perspectives. It is hoped to provide valuable insights for the widespread adoption of UV-C treatment technology.

Species of Diaporthe have broad host ranges and are widely distributed in ecosystems, occurring as plant pathogens, endophytes or saprobes. In this study, the ingredients and contents of phytohormones, organic acids, and fatty acids in 16 strains of Diporthe fungi, collected and identified from Xisha islands, were detected by LC-MS and GC-MS methods. Cluster analysis by Ward method of Euclid Distance was used to classify the quality types of different strains. The results showed that four phytohormones, three organic acids, and five fatty acids could be detected. The phytohormones included abscisic acid (ABA, average yield 125.36 µg/kg), indole-3-acetic acid (IAA, average yield 40.28 µg/kg), salicylic acid (SA, average yield 6.63 µg/kg) and jasmonic acid (JA, average yield 4.95 µg/kg). the yield of ABA was significantly higher than other plant hormones, and the four phytohormones contents of different strains varied greatly. Organic acids were succinic acid (average yield 336.04 µg/g), succinic acid (Vc, average yield 10.03 µg/g), shikimic acid (average yield 0.58 µg/g). The succinic acid production of Diporthe fungus was significantly higher than those of other organic acids. The yield of organic acids varied greatly among the 16 strains. The fatty acids were trans linoleic acid (average yield 58.99 µg/g), linolenic acid (average yield 28.15 µg/g), stearic acid (average yield 21.35 µg/g), palmitic acid (average yield 17.07 µg/g) and oleic acid (average yield 15.22 µg/g). The production of trans linoleic acid were the highest, while the production of oleic acid the lowest, and the five organic acids contents of different strains varied remarkably. Cluster analysis using plant hormones, organic acids, and fatty acids of the 16 strains revealed D. biconispora D43 was independent group. The strain showed the highest production of ABA (average yield 443.86µg/kg), succinic acid (average yield 1115.98 µg/g), shikimic acid (average yield 1.21 µg/g), and oleic acid (average yield 60.75 µg/g), while the lowest production of linoleic acid (average yield 7.08 µg/g). Comprehensive analysis suggests that D. biconispora D43 had certain potential for the development and utilization of microbial derived succinic acid. This study would provide information for the research and appication of Diaporthe resources in the field of food, chemical industry, and other related fields.

Biogenic volatile organic compounds (BVOCs) serve as a critical link between the biosphere and the atmosphere, playing a vital role in atmospheric chemistry, ozone formation, and the creation of secondary organic aerosols. Volatile emissions from urban forest parks and greenery can have a significant impact on local and regional air quality. In this study, two common Ficus spp. plants with a high planting rate in Haikou were selected, and the BVOCs emissions of F. elastica and F. altissima were measured using the dynamic headspace bagging collection method and identification and analysis by gas chromatograph. The chemical components and emission characteristics of the BVOCs were also investigated. Meanwhile, the experiment continuously monitored environmental factors [temperature (T), photosynthetically active radiation (PAR)] and physiological parameters [stomatal conductance (G_s), intercellular CO₂ concentration (C_i), transpiration rate (T_r)] to further analyze the driving factors of BVOCs emissions in Ficus spp. The results showed 19 and 12 compounds identified for F. elastica and F. altissima. BVOCs emissions from Ficus spp. were dominated by isoprene and terpenoids. Among them, the relative content of isoprene emission from F. elastica increased by 1.82 times in the rainy season compared to the dry season, indicating that F. elastica has a significant potential for isoprene emission. The terpene compounds α-pinene and Caryophyllene made significant contribution. The daily variation of BVOCs in Ficus spp. showed a single-peak emission pattern of “low in the morning and low in the evening, high in the middle of the day”, with the maximum emission of BVOCs occurring at 12：00 or 14：00 noon, when the temperature or photosynthetically active radiation was the highest. BVOCs emissions from Ficus spp. were significantly higher in the rainy season than they were in the dry season. In addition, the BVOCs emissions of Ficus spp. were positively correlated with the temperature and with the photosynthetically active radiation. BVOCs emissions were positively correlated with the physiological parameters, T_r and G_s, and negatively correlated with C_i. This study expands the research field by investigating the emission characteristics of BVOCs from tropical Ficus spp. It provides essential data for enriching the database of BVOCs emission inventories in tropical and subtropical regions and for assessing their environmental impact.

As a distinctive intertidal ecosystem at the interface between terrestrial and marine realms, mangrove represents a pivotal buffer against the influx of microplastics (MPs) into the marine environment, which serves as a principal repository for MPs. To elucidate the inner differences in the temporal alterations in micro-morphology, physicochemical traits and bacterial communities of polyvinyl chloride (PVC) and polylactic acid (PLA), exposure experiments were conducted at the representative artificial and natural mangrove communities in Dongzhaigang Mangrove Nature Reserve in Hainan Province. Results revealed that MPs cultured in the natural mangrove performed more pronounced collapses and substantial fluctuations in contact angle, crystallinity, and hydrophobicity in comparison to that in artificial mangrove environment. This suggests that the natural mangrove environment exposure might accelerate the MPs aging processes. Significant differences were observed between the diversity of MPs bacterial communities and sediments in artificial and natural mangrove (P<0.05). Firmicutes plays a dominate role in MPs exposed to natural mangrove communities, while Proteobacteria was the dominant phylum colonized on MPs in artificial mangrove environment. The pH level of natural mangrove sediments was the primary factor for bacterial colonization on “plastisphere” (P<0.01), whereas ammonium nitrogen (NH₄⁺-N) of artificial mangrove habitats showed a highly significant positive correlation (P<0.01) with the microbial community of MPs. In summary, MPs in natural mangrove communities showed more pronounced alterations in the surface micromorphology and microbial community succession than that in artificial mangrove communities. The surfaces of the “plastisphere” in natural mangrove communities have a high level of bacterial community richness, and their ability to enrich microorganisms differs from that of the “plastisphere” in artificial mangrove environment. Results of the study provide a foundation for the dynamic changes in physicochemical properties and microbial communities of MPs, which is expected to contribute to further investigations in the potential risks of MPs.

China's forestry informatization has entered the stage of smart forestry，and the new generation of information technology plays an important role in the smart forestry. Based on the connotation and development path of smart forestry, this paper refines the system architecture of smart forestry, expounds the research status of key technologies in smart forestry, such as Internet of Things, 3S and BeiDou Navigation, Cloud Computing, Big Data, Mobile Internet, etc., analyzes its main problems, and discusses its development trend and research focus. It is showed that there are some problems in the research of the key technologies of smart forestry in China, such as incomplete infrastructure, high cost, inconsistent technical standards, weak information interconnection, unstable data quality, data mining not deep enough, insufficient technology integration and lack of professional and technical talents. It is suggested that the research focus of the key technologies in China’s smart forestry in the future will be on four aspects: forestry data mining and deep application, forestry cloud remote sensing big data research, forestry block data research, and the deep integration of forestry internet of things, cloud computing, and mobile internet.