In this study, 12 coffee beans from Xishuangbanna (A, B, C), Pu’er (D, E, F), Lincang (G, H, I) and Baoshan (J, K, L) were used as the raw materials to analyze the contents of main flavor precursors and the differences of sensory products. The contents of protein, fat and reducing sugar were determined by the physicochemical analysis. The composition and content of amino acids in samples were determined by an automatic amino acid analyzer. The contents of caffeine and chlorogenic acid were determined by HPLC. 12 green coffee beans were roasted and the sensory quality was measured by cup. The color difference of coffee beans was analyzed by the Colorimetry system. The protein content ranging from 11.73 g/100 g to 14.72 g/100 g, the fat content ranging from 9.1% to 15.9%, the reducing sugar content ranging from 5.83 g/100 g to 6.26 g/100 g. 16 kinds of amino acids were detected in all the 12 samples, and methionine was not detected. The total amino acid content ranging from 10.18 g/100 g to 17.25 g/100 g. The total amino acid content of E coffee beans was the highest, and that of K coffee beans was the lowest. The caffeine content ranging from 13.73 mg/g to 15.74 mg/g, and the chlorogenic acid conten tranging from 20.97 mg/g and 32.51 mg/g. B coffee beans had the brightest color, better color scheduling and tone angle. J coffee beans were rudder than other coffees, and the hue angle was relatively poor. E coffee ripe beans and I coffee ripe beans tended to be blue. E coffee bean had better color scheduling and hue angle preference. The total score of sensory evaluation ranged from 42.79 to 46.09, the sensory score of L coffee bean was the highest, and the sensory score of A coffee bean was the lowest. Therefore, the content of main flavor components of raw coffee beans in different producing areas is different, and the sensory quality of cooked coffee beans in different producing areas is also different. The results are of great significance for the improvement of Yunnan coffee flavor quality and the screening and identification of high-quality products.

The variation of volatile aroma compounds and squalene-related enzyme activities of the tissue cultivation of Pandanus amaryllifolius Roxb. leaves (PAL) treated with different concentrations of Zn and La was studied. The volatile aroma compounds were analyzed by GC-MS, and the key enzyme activities of squalene metabolism were detected and analyzed. The results showed that there were differences in the number and content of volatile compounds in the tissue cultivation of PAL treated with different concentrations of trace elements. Compared with the untreated groud, 4 mg/L Zn treatment and 1 mg/L, 2 mg/L, 4 mg/L La treatment had more volatile compounds. Zn and La treatment increased the content of alcohols and decreased the content of olefins. Zn and La treatment significantly reduced the content of squalene. The treatment of 2 mg/L Zn increased the content of β-sitosterol, stigmasterol, ethyl palmitate, 3-methyl-2-(5H)-furanone, 2,3-dihydro-3,5-dihydroxy-6-methyl-4(h)-pyran-4-one, and decreased the content of squalene and phytol. The content of phytol in the leaves of 8 mg/L La treatment was the highest. The activities of squalene metabolism-related enzymes were changed in the process of tissue culture. Lanosterol synthase (LSS) activity and squalene epoxidase (SE) activity were stronger in the mixture, and squalene synthase (SQS) activity was stronger in adventitious roots. Different concentrations of trace elements had a certain effect on the activity of squalene-related enzymes. The content of squalene was positively correlated with LSS enzyme activity, SE enzyme activity and SQS enzyme activity in the PAL treated with different concentrations of Zn. The content of squalene in the tissue cultivation PAL treated with La was negatively correlated with LSS enzyme activity and SQS enzyme activity, and positively correlated with SE enzyme activity. The results would enrich the relevant theoretical research on the regulation of trace elements on the volatile aroma compounds of PAL, and provided theoretical basis for improving the aroma quality of PAL.

Dendrobium are famous for the ornamental and medicinal value. In order to explore the volatile components in the flowers of Dendrobium in Sect. Holochrysa and Sect. Chrysotoxae Kraenzl., the volatile components in the flowers of five Dendrobium in Sect. Holochrysa and seven Dendrobium in Sect. Chrysotoxae Kraenzl. were extracted by solid phase micro extraction (SPME) and analyzed via gas chromatography-mass spectrometry (GC-MS). Results showed that 74 volatile components were identified from the flowers of the species, 47 of which from D. hancockii in Sect. Holochrysa were the main volatile components; Secondly, there were 37 and 35 volatile components from D. chrysotoxum and D. harveyanum in the Sect. Chrysotoxae Kraenzl., respectively. The least component species was D. farmeri in the Sect. Chrysotoxae Kraenzl. with only 18 volatile components. Most of the species of volatile substances in Dendrobium were more than 20, and most of which were alkenes, except D. kenkinsii and D. densiflorum in the Sect. Chrysotoxae Kraenzl. mainly contained aldehydes. Cluster analysis of volatile ingredients showed that all the Dendrobium flowers were clustered together except a few Dendrobium plants were not clustered in the original grouping, which indicated that the volatile substances in Dendrobium flowers could be used as a reference for Dendrobium grouping. This study would provide references for the breeding, resource exploration and utilization of Dendrobium, and exert significant value on the grouping of Dendrobium.

Passion fruit (Passiflora edulis) is a characteristic and advantageous fruit in Guizhou, which is of great significance in poverty relief consolidation and the rural revitalization. However, in recent years, the viral diseases of passion fruit have become increasingly severe, leading to a sharp decline in yield and quality, which thereby seriously constrain industry development of passion fruit. In order to determine the virus species, distribution and compound infestation in the main plantation areas of passion fruit in Guizhou province, a total of 153 samples suspectedly infected by virus were collected from five main plantation orchards of passion fruit in five counties, i.e. Luodian, Congjiang, Rongjiang, Zhenning and Zhenfeng, and the virus detection was carried out by RT-PCR. The results showed that seven viruses were detected from the tested samples, namely East Asian Passiflora virus (EAPV), Telosma mosaic virus (TeMV), Cucumber mosaic virus (CMV), Turnip mosaic virus (TuMV), Passiflora mottle virus (PaMV), Passiflora latene carlavirus (PLV), and Potato virus Y (PVY), among which PVY infection was firstly reported from passion fruit. EAPV was the most prevalent one with infection rate as high as 96.08%, followed consecutively by TeMV (81.70%), CMV (78.43%), TuMV (44.44%), PaMV (26.80%), PVY (24.84%) and PLV (15.03%). In the present case, the distribution of passion fruit viruses in Guizhou province and the diversity of virus sequences were analyzed. Seven viruses were detected in Zhenning, six in Zhenfeng, five in Rongjiang and Congjiang, and three in Luodian. There’s a close identity between the nucleic acid of the seven detected viruses and the corresponding reference sequences (above 95%). Phylogenetic analysis revealed that EAPV, TeMV, PaMV, PLV and TuMV somewhat geographical clustered with passion fruit virus isolated from other provinces in China. CMV and PVY were most closely related to Cucumis melo CMV isolated from Spain and Capsicum annuum PVY isolated from Rwanda respectively, suggesting that the virus sequences diversely varies among the origins in China. A total of 24 types of mixed infection were detected in the main growing areas of passion fruit in Guizhou, and the complex infection rate was as high as 94.77%. The complex infection with 3-5 types predominated in the tested samples, and the combination of EAPV+TeMV+CMV was most frequent among the complex infections among which, EAPV, TeMV and CMV detected ranged from 78.43% to 96.08% in the five counties, somehow reflecting that they were the major viruses to prevent in passion fruit industry of Guizhou province. In addition, a multiplex PCR assay system for EAPV, TeMV and CMV was established in this study, which provides technical support for the rapid detection of related viruses.

To elucidate the differences in inter-root bacterial communities of Aquilaria sinensis, and to explore the correlation with soil physicochemical properties, we used the high-throughput sequencing technology and bioinformatics-related tools to analyze the composition and multi-characteristics of the inter-root soil bacterial community of A. sinensis. In three cultivation sites in Hainan province (Wenshan village, Haikou city, Dongguang farm, Lingao, and Baolun farm, Ledong), and combined with redundancy analysis to correlate the inter-root soil physicochemical proper-ties with the bacterial community. The results showed that a total of 7 944 402 sequences belonging to 51 phyla,151 orders, 380 families, 637 families, 1296 genera and 2649 species were obtained among the sites; the variability of bacterial community and diversity of A. sinensis in the sample sites was not significant, and there were significant differences among the sample sites. The richness and diversity of inter-root soil bacteria in the sites were as follows: LDJX>LDWJ>LGWJ>LGJX>WSWJ>WSJX. In terms of community structure, the Ledong sample site differed significantly from the Wenshan and Lingao sample sites in terms of community structure.at the phylum level, the dominant bacterial phyla in Ledong were Planctomycetota, Chloroflexi, and Verrucomicrobiota; the dominant populations in Wenshan and Lingao were Firmicutes, Bacteroidota, and Proteobacteria. At the genus level, the dominant genera in Wenshan and Lingao were Bacteroides, uncultured_bacterium_f Muribaculaceae, and Faecalibacterium; the dominant genera in Ledong were the unidentified genus (g_uncultured_f__Gemmataceae) genus, Candidatus_Udaeobacter, and Bacteroides. The RDA analysis revealed that the inter-rhizosphere soil bacterial community of A. sinensis was affected by soil physicochemical factors with some differences among different sites. Total phosphorus was significantly and negatively correlated with bacterial population differences and diversity, and pH was significantly and positively correlated with bacterial population differences and diversity. The results are valuable for studying the interactions of inter-root microorganisms of A. sinensis, and have certain guiding significance for the development of Hainan incense industry.

Rhizosphere is a dynamic interface where soil, plant roots and microorganisms exchange substances. Rhizospheric actinomycetes are an important component of root actinomycetes and one of the main sources of bioactive substances. In this study, five different rhizospheric soil samples of a mangrove plant, Acanthus ilicifolius, were collected from the Dongzhaigang Mangrove Nature Reserve of Hainan province. A combination of high-throughput sequencing and traditional pure culture strategies were used to explore the diversity of the rhizospheric actinomycetes of A. ilicifolius and the potential to produce bioactive substances in the samples. The V3 to V4 regions of 16S rRNA gene in the rhizospheric samples of A. ilicifolius were sequenced and analyzed by Illumina Novaseq 6000 sequencing platform. A total of 32 phyla (including 25 effectively identified phyla) were annotated, of which Proteobacteria is the dominant phyla. α-diversity analysis showed that the rhizospheric bacterial community of A. ilicifolius was very abundant. The microbial communities of actinomycetes were analyzed, and 33 validated genera, four tentative genera and 28 uncultured new genera were noted. KEGG functional prediction analysis in different levels showed that rhizospheric actinomycetes were mainly involved in the biosynthesis of secondary metabolites including various antibiotics. Meanwhile, actinomycetes were isolated by the traditional pure culture method. After isolation, purification, morphological characteristics grouping and rearrangement, the diversity of actinomycetes of mangrove A. ilicifolius was analyzed by PCR amplification, sequencing and comparison of 16S rRNA gene sequences. The antimicrobial activity was screened by the agar diffusion method. PCR-based gene screening technology was used to detect the possible antibiotic biosynthesis genes of the representative strains of PKS-I, PKS-II and NRPS. A total of 33 representative strains of rhizospheric actinomycetes were obtained from four genera, of which Streptomyces was the dominant genus, and 2 genera could not be detected by high-throughput sequencing method. The positive rates of NRPS and PKS-II genes of the representative strains were very high (more than 90%). 24.24% of rhizospheric actinomycetes had the activity against at least one or more indicator microorgnisms. In this study, high-throughput sequencing and traditional pure culture methods were used to show that rhizospheric actinomycetes of a mangrove plant A. ilicifolius from Dongzhaigang had a very rich actinomycetic diversity. The rhizospheric actinomyces of A. ilicifolius has good potential to synthesize secondary metabolites, which could provide rich microbial resources for the screening of bioactive compounds, and also provide an important basis for the development of subsequent new drugs.

The plant species in eight coastal parks in Xiamen island were investigated by the sample line method and a total of 288 species of plants in eight coastal parks on Xiamen island were obtained, among which 127 were introduced plants, accounting for 44.10% of the total. 80 species of exotic garden plants with invasive potential were obtained. The risk assessment system of invasive ornamental introduced plants in Xiamen island coastal parks was constructed by the literature collation method and expert consultation, and the evaluation index weights were determined by the hierarchical analysis method. The evaluation system includes one target level, five primary indicators and twenty secondary indicators. 80 exotic landscape plants with invasive potential were substituted into the risk assessment system of introduced landscape plants in Xiamen island Coastal Park to obtain the corresponding scores. 13 species with scores between 38.00 and 58.85 were considered high-risk plants. 18 species with scores between 23.00 and 38.00 were medium-risk plants. Nine species with scores between 9.30 and 23.00 were low-risk plants. Four high-risk plants that are not listed in the Chinese Invasive Alien Plant Register should be detected early and controlled with effective management measures. Medium-risk plants should be phased out and replaced with native plants, and low-risk plants should be monitored and managed. Most of the ornamental introduced plants in the eight coastal parks in Xiamen island are low-risk plants. Among them, Wutong Lighthouse Park, Bay Park and Niu Tou Mountain Park are among the top three in the number of applied introduced plant species, and it is recommended that no more ornamental introduced plants be introduced in the future. Music Square had the least number of introduced plants, and it is recommended to introduce low-risk plants to increase the vegetation diversity of the park. This study sorts out the introduced plant species in Xiamen island coastal parks and proposes relevant control suggestions for introduced plants, protects the ecological security of Xiamen island coastal parks, further enriches the invasion risk evaluation studies in small-scale areas and provides a reference for the introduction of introduced plants in coastal parks in other areas.

Plasma membrane intrinsic proteins (PIPs), which belong to the aquaporin (AQP) family within the major intrinsic protein (MIP) superfamily, are known for the high water transport activity at the cell membrane. The subfamily is highly conservative and only includes two phylogenetic groups named PIP1 and PIP2. Natural rubber, an important industrial raw material and strategic material, is mainly derived from Para rubber tree (Hevea brasiliensis Muell. Arg.), a big tree originated in the Amazon basin of South America. As a special tissue for rubber synthesis and storage, the laticiferous cells possess no plasmodesmata with neighboring parenchyma cells, and the water balance is mainly mediated by PIP aquaporins. In previous studies, a highly abundant PIP gene denoted HbPIP1;4 was identified, however, no detectable water transport activity was found when heterologously expressed in Xenopus laevis oocytes, which may be due to its inability to localize to the cell membrane. To uncover the acting site and multimerization features of HbPIP1;4 in vivo, recombinant plasmids pNC-Cam1304-SubN-HbPIP1;4, pNC-BiFC-ECN-HbPIP1;4, and pNC-BiFC-ENN-HbPIP1;4 for subcellular localization and bimolecular fluorescence complementation (BiFC) were successfully constructed. Agrobacterium tumefaciens transformed with above recombinant plasmids were used to infiltrate tobacco (Nicotiana benthamiana), and transiently transformed leaves were subsequently checked using laser confocal microscopy. Compared with wide distribution of fluorescence signals throughout the cell for the control pNC-Cam1304-SubN, signals of pNC-Cam1304-GFP-HbPIP1;4 were restricted to the cell membrane, supporting the plasma membrane localization of HbPIP1;4, which is consistent with the bioinformatics prediction. The result was further supported by the BiFC analysis, which also implied that HbPIP1;4 could form homomultimer, in accordance with the 3D prediction via homology modeling. The results would lay a solid foundation for further uncovering the mechanism of water balance of the laticifer. Nevertheless, PIP aquaporins that could interact with HbPIP1;4 in rubber tree remain to be further characterized.

Sporisorium scitamineum, the pathogen of destructive disease smut, usually causes abnormal growth of meristematic tissue and forms a “black whip” in meristem tissues. In some cases, it induces formation of flowering structures in some sugarcane cultivars (genotypes), but the exact mechanism remains unclear. In order to explore flowering related genes and the expression patterns in sugarcane in response to infection by S. scitamineum, the healthy and S. scitamineum infected ‘guitang42’ sugarcane cultivar samples were analyzed by transcriptome sequencing. A total of 3276 differentially expressed genes (DEGs) were identified, of which 1677 genes were up-regulated (P<0.05) and 1599 genes down-regulated (P<0.05). The DEGs were mostly enriched in the biosynthesis process, ribosome, ribonucleoprotein complex, ribosome structural components, etc. according to GO enrichment analysis. The KEGG analysis showed that the DEGs were mostly enriched in amino acid biosynthesis, purine metabolism, carbon metabolism, phagocytosis, and other metabolic pathways. Also, out of 30 DEGs were identified to be associated with flowering, and the representative genes such as FT1, PIE1, GID1, GA20ox-1, GA20ox-2 were validated by qRT-PCR. The qRT-PCR results were consistent with the transcriptomic data, confirming the dependability of the transcriptome sequencing results. The findings would present essential candidate genes for revealing the mechanism of early flowering of sugarcane plants caused by S. scitamineum, and lay the foundation for disease resistance breeding.

Leaf photosynthesis is the energy source of plant life activities. However, some macadamia varieties (Macadamia integrifolia) planted in southern China are prone to generate the etiolated leaves under the continuous high temperature in summer, which seriously affects the shoot growth and fruit production of macadamia trees. In order to explore the mechanism of photosynthetic energy generation in the etiolated leaves of macadamia, the genes related to photosynthetic energy metabolism were identified and screened in this study, based on the previously obtained transcriptome sequencing data from the leaves of HAES344 macadamia at different yellowing stages, and the expression changes of the key genes in photosynthetic energy metabolism were analyzed during leaf yellowing of HAES344 macadamia by qRT-PCR. 96 genes with differential expression in the etiolated leaves of HAES344 macadamia were identified to be related to energy metabolism according to KEGG functional annotation and enrichment analysis, and the number of the differentially expressed genes enriched in the oxidative phosphorylation pathway was the highest, followed by carbon fixation pathway, and the least genes were enriched in the antenna proteins. After screening (RPKM>0.5), a total of 43 genes related to photosynthetic energy metabolism were obtained. Among these genes, the expression level of 27 genes decreased significantly in the yellowed leaves, while the remaining 16 genes did the opposite. Through the qRT-PCR analysis of the relative expression level of key functional genes in the photosynthetic energy metabolism, the CAP10A gene encoding photosystem Ⅱ (PSⅡ) antenna protein, the ATPC and ATPF genes encoding ATPase subunit protein, the enzyme genes related to carbon assimilation (GAPA, GPD, At4g2652 and rbcL), the Os05g0200100 and CXXS1 genes encoding thioredoxin, and the TIC32 gene associated with plastid protein transmembrane transport showed a significant lower transcription level in the etiolated leaves of HAES344 macadamia compared with the normal leaves, while the SIR and APR3 genes related to sulfur metabolism and the PGR5, ndhB and ndhD genes mediating cyclic electron transfer did the opposite, which suggested that the greatly changed expression patterns of genes related to photosynthetic energy metabolism affected the production of photosynthetic energy in the macadamia yellowing leaves. The results of this study would provide a reference for further exploring the mechanism of photosynthetic energy metabolism-related genes in the etiolated leaves of macadamia.