Intercropping is widely promoted to sustain soil function, yet evidence for its application in rubber-based agroforestry, particularly with the shade-tolerant herb Amomum villosum, is limited. We evaluated whether A. villosum intercropping improves soil properties and reorganizes microbiomes across the vertical profile of mature rubber plantations. Soil samples were taken at 0–10, 10–20, and 20–30 cm depths in both intercropped and monoculture stands. Physical and chemical properties were quantified, and bacterial (16S rRNA V3–V4) and fungal (ITS2) communities were analyzed using high-throughput amplicon sequencing with depth-resolved data on diversity, composition, and functional inference (FAPROTAX, FUNGuild). Intercropping consistently improved soil structure and fertility, with the strongest effects at 0–10 cm. Total porosity (12%), organic matter (38.9%), alkali-hydrolyzable nitrogen (75.4%), and available phosphorus (131%) were markedly higher than in monoculture. Benefits extended to mid-depth with a 65.2% increase in alkali-hydrolyzable nitrogen. Microbial richness (bacteria and fungi) increased, and communities separated clearly by treatment and depth. Intercropped soils showed higher relative abundances of copiotrophic and particle-attached phyla (e.g., Proteobacteria, Planctomycetota), while Acidobacteriota and several Chloroflexi declined. Nitrospirota increased with depth. Fungal trophic structure shifted away from pathotrophs at 20–30 cm and toward symbiotrophs, particularly arbuscular mycorrhizal lineages, at subsurface layers. Functional predictions indicated greater potential for nitrogen transformations (e.g., nitrogen fixation, nitrification), greater C₁/hydrocarbon utilization, and a reduced bacterial plant-pathogen signal under intercropping. Collectively, A. villosum intercropping reorganizes the soil environment and microbiome in mutually reinforcing ways—improving physical structure, enlarging near-term nitrogen supply, and favoring beneficial fungal guilds. These depth-resolved effects help explain the agronomic appeal of rubber–A. villosum systems and support their wider deployment in rubber plantations.

Climate change is reshaping the geographic envelope of rubber cultivation in China, creating risks of maladaptation from ill-informed expansion or abandonment of viable regions. We compared five species distribution models (GLM, RF, BRT, MaxNet, and MaxEnt) under identical samples and spatial cross-validation, then projected suitability to 2100 under CMIP6 scenarios. MaxEnt demonstrated the highest accuracy and transferability (AUC 0.973, TSS > 0.90) and was retained for final projections. Isothermality and dry-season precipitation emerged as primary limiting factors. Under moderate emissions (SSP245), highly suitable areas expand by 153% by 2100 with a northward shift, whereas extreme warming (SSP585) triggers heat and drought stresses that limit expansion. Integrating MaxEnt outputs with Marxan spatial optimization identified 480 priority planning units covering 1.9% of the national territory at minimal cost. This workflow translates climate-sensitive suitability into actionable spatial priorities, supporting resilient development of China’s rubber sector under uncertainty.

Hevea brasiliensis and Taraxacum kok-saghyz are sources of natural rubber (NR) and recent research has focused on finding a method to increase NR production and quality. NR consists mainly of cis-1,4-polyisoprene, which is synthesized from sucrose by a series of reactions during carbon metabolism. WRINKLED1 (WRI1) is a transcription factor (TF) that coordinates many genes involved in carbon metabolism and lipid biosynthesis. Here, we isolated and characterized two orthologues of WRI in rubber-producing plants H. brasiliensis and T. kok-saghyz, which are highly expressed in their latex. Subcellular localization and ectopic expression in Arabidopsis thaliana indicated that the TFs, HbWRI1 and TkWRI1, are involved in lipid accumulation. Overexpression of HbWRI1 and TkWRI1 in T. kok-saghyz substantially enhanced NR production and quality, including dry rubber content, molecular weight, and the diameter of rubber particles. Conversely, they were substantially decreased in TkWRI1 repression. Furthermore, based on the activated expression in transgenic T. kok-saghyz latex and the existence of AW-box element in the promoter regions, 16 direct downstream genes of HbWRI1 and TkWRI1 were identified by a dual-luciferase reporter assay and yeast one-hybrid assay, and their products were responsible for rubber biosynthesis or lipid metabolism. These results reveal a regulatory module that HbWRI1 and TkWRI1 TFs can positively regulate NR production and quality in T. kok-saghyz latex by coordinately regulating the entire rubber biosynthesis. This module is expected to be utilized to develop superior varieties to enhance NR production and quality.

BACGROUND: Coffee peel, a major by-product of coffee processing, holds considerable economic potential. Presently, the majority of scientific research is concentrated on coffee beans, while studies focusing on the coffee peel remain insufficiently explored. In this study, the dynamic changes in flavonoids and associated regulatory genes in the coffee peel were systematically analyzed at four distinct maturity stages using transcriptomic and metabolomic approaches, complemented by the assessment of physical and chemical indicators. RESULTS: A total of 234 flavonoid metabolites were identified in this study, of which 83 exhibited significant differential expression. The key flavonoid metabolites identified during the maturation of coffee peel included morin, prunetin, naringenin, pinobanksin, and phlorizin. Correlation analysis revealed that the genes encoding CHS, CYP73A, and CYP75B1 were significantly positively correlated with most flavonoid metabolites. CONCLUSION: The study revealed a significant accumulation of flavonoids in coffee peel during the maturation process. Enzymes encoded by genes such as CHS, CYP73A, and CYP75B1 exerted significant positive regulatory effects on most flavonoids in the pathway and could serve as key candidate genes for studying the regulation of flavonoid metabolism during coffee peel development. These findings contribute to enhancing the utilization of coffee by-products in the industry and provide a foundation for future molecular breeding efforts focused on coffee varieties enriched with flavonoids.

Rubber plantations biomass is a crucial indicator for assessing carbon storage and ecological functions within Rubber plantation ecosystems. However, improving the accuracy of biomass estimation remains a key research focus. Slope and aspect indirectly regulate rubber tree growth by influencing water, nutrient, and light conditions. The potential of topographic factors to enhance model accuracy remains uncertain. This study aims to enhance the accuracy of biomass estimation in rubber plantations by integrating drone-based multispectral imagery and topographic factors, while evaluating twelve machine learning algorithms, including deep learning models. The research was conducted in Menglian County, Yunnan Province, a mountainous region with complex terrain, utilizing spectral, textural, and topographic features to estimate aboveground and belowground biomass across different age classes (young, intermediate, mature, over-mature) of rubber forests. Twelve regression models were tested, including linear models (MLR, PLSR), ensemble methods (RF, XGBoost, GB), support vector machines (SVM), K-nearest neighbors (KNN), and deep learning models (ANN, BPNN, CNN, U-Net DRM, PINN). Random forest regression was employed for feature selection, reducing the input variables from 325 to a lower dimension. The XGBoost model maintained the highest accuracy among the 12 models, achieving R² > 0.95, the lowest RMSE (∼27.653 t/hm²), and Bias (4.700 t/hm²). Ultimately, the XGBoost model was selected to estimate biomass of rubber plantations. The results showed that the average biomass of young rubber plantations was 264.698 t/hm², middle-aged plantations 351.539 t/hm², mature plantations 330.649 t/hm², and over-mature plantations 420.315 t/hm². The high-precision biomass estimation framework integrating UAV-based multispectral data and topographic factors significantly improves model performance. This approach not only provides a reliable technical framework for accurate biomass estimation in rubber plantation ecosystems but also offers robust technical support for dynamic monitoring and assessment of carbon storage in tropical artificial forest plantations.

Propagation of rubber tree (Hevea brasiliensis) via secondary somatic embryogenesis (SSEis) is a reliable method. However, its efficiency is relatively low. The aim of this study was to understand more about the factors related to SSEis in rubber trees, trying to improve the efficiency of somatic embryo (SE) yield. Our study showed that the orientations of explants, i.e., the fragments of primary SE (PSE), on the medium affected secondary SE (SSE) yield significantly. Among five experimental tests, the highest yield was 2.6 ± 0.9 secondary somatic embryos (SSEs) per explant, which was achieved by orienting the abaxial side of the explant in contact with the medium and then the adaxial side after a period of culture time. Based on histological evidence, SSEis was induced from the epidermal cells and adjacent cells on the adaxial side of the explants. A remarkable difference in embryogenic capacity difference existed among individual PSE. The concentrations of soluble proteins, starch, soluble sugars, and the superoxide dismutase activity (SOD) levels in the explants were measured during a 25-day long SSEis induction treatment and compared between explants of high and low embryogenic capacity. This study proves that the explant orientation toward the culture medium plays a crucial role in SSEis, while the concentration changes of these biochemical compounds correlate to morphological changes in the explants during induction, as do the changes in SOD activity. Furthermore, the trend of the dynamic changes in the explants reflected a process of de-differentiation and re-differentiation, which started from mature SE tissues during SSE induction.

The plant microbiome plays a role in pathogen defense, but its role in different resistant varieties and ecological niches remains unclear. This study used 16S rRNA and ITS sequencing to investigate microbial communities and interactions in disease-resistant (PT) and susceptible (Bourbon) coffee varieties of five ecological niches: leaves, fruits, roots, rhizosphere soil, and non-rhizosphere soil. We found that the microbial communities differed significantly between the two varieties. The resistant variety was enriched in beneficial bacteria from the Actinobacteriota phylum and a stable, modular microbial network dominated by saprotrophic fungi. In contrast, the susceptible variety had a higher abundance of opportunistic pathogens and stress-indicator fungi, including Neurospora spp., which were more prominent in the rhizosphere and non-rhizosphere soils. These networks were fragile and dominated by pathotrophic fungi, reflecting ecological imbalance. Our findings show that plant disease resistance is influenced not only by host genetics but also by co-evolutionary interactions with the microbiome. These insights provide a foundation for developing targeted biocontrol strategies to manage plant-associated microbial communities.

Plant–microbe interactions in soil rhizosphere driven by root exudate metabolites are receiving increasing research attention. Medicinal plants possess a wide range of root-derived metabolites with unique characteristics. It is pertinent to understand how root systems of medicinal plants influence microbial populations in the rhizosphere. This work involved high-throughput sequencing of microorganisms, root exudate analysis with gas chromatography, and time-of-flight mass spectrometry. Soil rhizospheres of three varying Amomum villosum root diameters revealed a diverse microbiome and root exudate metabolites. Metabolite contents in root exudates and the relative abundance of Acidobacteria and Chloroflexi significantly differed in the rhizospheres of three varying diameters of A. villosum. Moreover, root exudates promoted the growth of Actinobacteriota, Basidiomycota, and Proteobacteria while inhibiting that of Acidobacteriota and Chloroflexi in soil rhizospheres. Our results suggest that root exudates, associated with root diameter, changed the microbiome diversity of the soil rhizosphere.

The interactions between plants and rhizosphere microbes mediated by plant root exudates are increasingly being investigated. The root-derived metabolites of medicinal plants are relatively diverse and have unique characteristics. However, whether medicinal plants influence their rhizosphere microbial community remains unknown. How medicinal plant species drive rhizosphere microbial community changes should be clarified. In this study involving high-throughput sequencing of rhizosphere microbes and an analysis of root exudates using a gas chromatograph coupled with a time-of-flight mass spectrometer, we revealed that the root exudate metabolites and microorganisms differed among the rhizosphere soils of five medicinal plants. Moreover, the results of a correlation analysis indicated that bacterial and fungal profiles in the rhizosphere soils of the five medicinal plants were extremely significantly or significantly affected by 10 root-associated metabolites. Furthermore, among the 10 root exudate metabolites, two (carvone and zymosterol) had opposite effects on rhizosphere bacteria and fungi. Our study findings suggest that plant-derived exudates modulate changes to rhizosphere microbial communities.

Table grapes are perishable crops with a high susceptibility to postharvest phytopathogens. Use of natural phytochemicals as elicitors for improving crop quality and enhancing the natural resistance against postharvest pathogens is a novel approach. Calcium ascorbate (CaAs) is an ecofriendly and inexpensive compound used as anti-browning agent in fresh cut fruits and minimally processed products. Thompson seedless table grapes (Vitis vinifera L.) were treated with calcium ascorbate (CaAs) at 0, 5

The genetic relationships between Coffea arabica resources were analyzed via specific length amplified fragment sequencing (SLAF-seq) and transcriptome sequencing to provide the theoretical basis for breeding new varieties. Twenty C. arabica accessions were used to analyze genetic diversity on the basis of SNPs identified in SLAFs and the transcriptome data. For the SLAF-seq analysis of 20 C. arabica accessions, two Coffea canephora accessions, one Coffea liberica accession, and one Coffea racemosa accession, the number of reads ranged from 2,665,424 to 7,210,310, with a GC content of 38.49%–40.91% and a Q30 value of 94.99%–96.36%. A total of 3,347,069 SLAF tags were obtained, with an average sequencing depth of 13.90×. Moreover, the 1,048,575 SNPs identified in the polymorphic SLAFs were filtered, then the remaining 198,955 SNPs were used to construct a phylogenetic tree, perform a principal component analysis, and characterize the population structure. For the transcriptome analysis, 128.50 Gb clean reads were generated for the 20 C. arabica accessions, with a GC content of 44.36%–51.09% and a Q30 value of 94.55%–95.40%. Furthermore, 25,872 genes’ expression levels were used for the correlation analysis. The phylogenetic relationships as well as the results of the principal component analysis, population structure analysis, and correlation analysis clearly distinguished C. arabica Typica-type accessions from the C. arabica Bourbon-type accessions. Notably, several C. arabica local selections with unknown genetic backgrounds were classified according to all four clustering results.

The color of coffee fruits is influenced by several factors, including cultivar, ripening stage, and metabolite composition. However, the metabolic accumulation of pigments and the molecular mechanisms underlying peel coloration during the ripening process of Coffea arabica L. remain relatively understudied. In this study, UPLC-MS/MS-based metabolomics and RNA sequencing (RNA-seq)-based transcriptomics were integrated to investigate the accumulation of anthocyanins and carotenoids in the peel of Coffea arabica at different ripening stages: green peel (GP), green-yellow peel (GYRP), red peel (RP), and red-purple peel (RPP). This integration aimed at elucidating the molecular mechanisms associated with these changes. A total of ten anthocyanins, six carotenoids, and thirty-five xanthophylls were identified throughout the ripening process. The results demonstrated a gradual decrease in the total carotenoid content in the peel with fruit maturation, while anthocyanin content increased significantly. Notably, the accumulation of specific anthocyanins was closely associated with the transition of peel colors from green to red. Integrated metabolomics and transcriptomics analyses identified the GYRP stage as critical for this color transition. A weighted gene co-expression network analysis (WGCNA) revealed that enzyme-coding genes such as 3AT, BZ1, and lcyE, along with transcription factors including MYB, NAC, and bHLH, which interact with PHD and SET TR, may regulate the biosynthesis of anthocyanins and carotenoids, thereby influencing peel pigmentation. These findings provide valuable insights into the molecular mechanisms underlying the accumulation of anthocyanins and carotenoids in Coffea arabica peel during fruit maturation.

Hevea brasiliensis and Taraxacum kok-saghyz are sources of nature rubber (NR) and recent research has focused on finding a method to increase NR quality and production. NR consists mainly of cis-1,4-polyisoprene, which is synthesized from sucrose by a series of reactions during carbon metabolism. WRINKLED1 (WRI1) is a transcription factor (TF) that coordinates many genes involved in carbon metabolism and lipid biosynthesis. Here, we isolated and characterized two orthologues of WRI in rubber-producing plants H. brasiliensisa and T. kok-saghyz, which are highly expressed in their latex. Subcellular localization and ectopic expression in Arabidopsis thaliana indicated that the TFs, HbWRI1 and TkWRI1, are involved in lipid accumulation. Overexpression of HbWRI1 and TkWRI1 in T. kok-saghyz substantially enhanced NR quality and production, including dry rubber content, molecular weight, and the diameter of rubber particles in the latex. Conversely, they were decreased in TkWRI1 repression. Furthermore, based on the activated expression in transgenic T. kok-saghyz latex and the existence of AW-box element in the promoter regions, 16 direct downstream genes of HbWRI1 and TkWRI1 were identified by a dual-luciferase reporter assay and yeast one-hybrid assay, and their products were responsible for both NR biosynthesis and lipid metabolism. These results reveal a regulatory module that HbWRI1 and TkWRI1 TFs can positively regulate NR quality and production in T. kok-saghyz latex by synergistically regulating the entire NR biosynthesis. This module is expected to be utilized to develop superior varieties to enhance NR quality and production.

The forest–medicinal plant management system has benefited the commercial production of Amomum villosum. However, little is known about the influence of different forestlands on the cultivation of A. villosum. The present study investigated the potential differences in the A. villosum yield and quality parameters, rhizosphere soil properties, and rhizosphere soil microbiota between a rubber plantation (RP) and a natural secondary forest (NSF). No significant differences in yield or rhizosphere soil properties of A. villosum were observed between RP and NSF, although most of the A. villosum yield parameters, the rhizosphere soil physicochemical properties, and soil enzyme activities were higher in NSF than in RP. Furthermore, the 38 volatile components had significantly higher relative abundances in NSF than in RP. Furthermore, the alpha diversity indices for the microbiota communities in the A. villosum rhizosphere soil indicated that the richness of the bacterial and fungal communities was significantly higher in NSF than in RP. These findings suggest that NSF conditions may be more appropriate than RP conditions for growing A. villosum. The data generated in this study may be useful for increasing the production of high-quality A. villosum via the exploitation of natural environments.

Coffee is one of the most valuable agricultural commodities worldwide, second only to oil in terms of international trade. Coffea arabica L. is a widely cultivated and economically important crop that is responsible for about 90% of the global production of coffee. In this study, we selected five C. arabica cultivation sites at different altitudes to clarify the effects of altitude on rhizospheric soil physical–chemical characteristics and microbial communities. The samples collected at low altitudes were more nutrient-deficient and acidic than the soil samples collected at medium–high altitudes. The Proteobacteria-to-Acidobacteria ratio increased from lower altitudes to medium–high altitudes. Additionally, although Ascomycota was the dominant fungal phylum, it was unaffected by the altitude. Furthermore, the alpha richness and diversity of the bacterial and fungal communities were higher at medium–high altitudes than at low altitudes. Moreover, the redundancy analysis indicated that microbial phyla were closely associated with pH. These findings suggest that C. arabica should be cultivated at medium–high altitudes, which is conducive to sustainable management and the production of high-quality C. arabica beans.

Bletilla striata is an important Chinese herbal plant grown widely in southwest China (Qian et al. 2021). Leaf blight was found on cultivated bletilla crops in Yunnan in 2021. The disease infected bletilla leaves and it was present in the field from April to November with the highest incidence (86% plants diseased) recorded in early September in Puer area. Foliar lesions were circular (Φ0.5-1.8 cm) or oval, with pale-gray center and narrow gray-brown outer area surrounded by a yellow halo. The lesions coalesced later to form large irregular spots or blighted areas on leaves. Symptomatic bletilla leaves were sampled from fields in Jiangcheng (E101.8672o, N22.5803o) and Simao (E109.7816o, N22.7891o) counties, Yunnan in July 2021. Seven fungal isolates were obtained from (BJ01-BJ04) and Simao samples (HBJ05-HBJ07) via lesion-tissue culture and hypha-tip purification on PDA medium. A pathogenicity test following Koch's Postulates (Grimms et al. 2006) was conducted using each isolate by inoculating 45-day old bletilla plant (n=30, Zihua cultivar) in a greenhouse through spraying hypha-spore suspension (3.25×104 CFU/mL) prepared with 14 d fresh DNA culture. Non-inoculated plants (n=30) were used as controls. The experiment was repeated once. The isolates BJ02 and HBJ06 (deposited in Yunnan Agric. Univ. Microbes Herbarium) were shown pathogenic to bletilla since similar lesions formed on seedlings 7 d post inoculation and pure fungal cultures with the same colony morphology as those of BJ02 and HBJ06 were re-isolated from leaf lesions 14 dpi. Isolates BJ02 and HBJ06 produced identical colony and conidium morphology after they were incubated at 25oC for 7 d on PDA. Colonies were circular, pale brown, Φ5.5-7.5cm, with villous surface and abundant aerial hyphae. Mycelia were septate, colorless, Φ3-4 µm and with acute-angled branches. Conidiophores developed from hyphae were erect, septate, pale-brown colored and 60-200 µm long. Conidia (produced scarcely and ripened slowly) were long-oval or petaloid, straight or slightly curved, brown, sized 28-45×10-14 µm. Most conidia were divided into 4 cells by 3 septa; the middle two were bigger than the basal and apex cells. Both BJ02 and HBJ06 were identified as Curvularia sp. based on their morphological characters (Tan et al. 2018). The rDNA-ITS, TEF1α and GAPDH genes (Tan et al. 2018) were amplified from these isolates with PCR (White et al. 1990) and sequenced. ITS sequences of the two isolates were both 574 bp (acc. no. OL587997 & OL336480) and 100% (574/574 bp) identical shown by blast comparison. Further blast analyses of ITS (574 bp, OL587997), TEF1α (532 bp, ON637120) and GAPDH (881 bp, ON637121) from isolate BJ02 showed that they were 99.27% (547/551 bp), 100% (842/842 bp) and 99.8% (507/508 bp) identical respectively with those of Curvularia reesii BRIP4358 (MH414907). The 3 genes of BJ02 were concatenated and phylogenic analysis (Tamura et al, 2013) of the concatenated sequence with those of Curvularia spp. showed that BJ02 was clustered with C. reesii BRIP4358 on the same end-branch of the tree with 100% confidence. Therefore, BJ02 and HBJ06 are the same species identified as Curvularia reesii and it is the pathogen causing bletilla leaf blight. C. reesii was first isolated from the air in Australia in 1963 and was named by Tan et al. in 2018. It has not been reported as a plant pathogen elsewhere. This is the first record of this fungus causing bletilla leaf blight in China. Keywords: Bletilla striata; leaf blight; Curvularia reesii; disease symptoms; pathogen morphology; multigene identification References (1) D.J. Grimes. Microbes, 1(5): 223-228, 2006. (2) L.H. Qian et al. Jiangshu Agric. Sci. 49(19): 64-71, 2021. (3) K. Tamura et al. Mol. Bio. & Evol. 30 (12): 2725- 2729, 2013. (4) Y. P. Tan et al. MycoKeys, 35: 1-25. 2018. (5) T.J. White et al. In: PCR Protocols: A Guide to Methods and Applications (eds. M.A. Innis et al.), Acad. Press, Inc. New York. 315-322, 1990.

为探究橡胶林下间作砂仁对根际及非根际土壤微生物数量丰度的影响,以橡胶树单作、砂仁单作和橡胶树/砂仁间作的根际和非根际土壤作为试验材料,测定了不同处理后非根际土壤和根际土壤中细菌、真菌、放线菌的数量.结果表明:橡胶树/砂仁间作能显著提高砂仁根际土壤中细菌、真菌和放线菌的数量;与砂仁相比,间作后橡胶树根际土壤中细菌和放线菌数量增加极显著(P＜0.01),真菌数量较橡胶树单作差异不显著(P＞0.05).在非根际土壤中,间作模式下土壤中的细菌、真菌、放线菌数量分别达到11.46 × 108CFU/g、8.22 × 105 CFU/g和3.32 × 104 CFU/g,均显著高于橡胶树单作和砂仁单作.不同处理下3种土壤微生物类群的数量变化都呈现同一种趋势,即橡胶树/砂仁间作＞橡胶树单作,橡胶树/砂仁间作＞砂仁单作.由此可见,在成龄胶园间作砂仁能够有效提高砂仁根际土壤中和非根际土壤中的微生物数量丰度,改善其微生态环境,这一结果为揭示橡胶树间作砂仁模式下的土壤微生物生态学研究奠定了理论基础.

目的:白及叶枯病于2021年首次在云南栽培白及上被发现,本研究旨在描述该病害的症状和病原菌形态特征;分离纯化和鉴定其病原菌.方法:用病组织分离法和菌丝尖端纯化法获得真菌菌株,用柯赫氏证病试验确定致病菌;通过PCR扩增获得致病菌株的ITS序列,由此做Blastn和系统树演化分析,结合形态特征鉴定病原菌.结果:该病害侵染叶片形成褐色圆形至椭圆形典型病斑,病斑后期扩展使叶缘或叶尖大面积枯死,重病植株可枯死.致病性试验结果表明分离纯化获得的真菌菌株BJ02为白及叶枯病的致病菌.菌株BJ02在PDA培养基上长出的菌落、分生孢子梗和分生孢子特征与水稻弯孢菌和里斯弯孢菌的形态相似.PCR扩增获得菌株BJ02的ITS片段长度为574 bp(OL587997),Blastn分析表明该序列与里斯弯孢Curvularia reesii(菌株BRIP4358)的ITS序列(MH414907)相似率达99.27％,在系统演化树上,菌株BJ02与菌株BRIP4358聚集于同一末端分枝(置信限100％).结论:菌株BJ02为里斯弯孢菌Curvularia reesii Y.P.Tan&R.G.Shivas,该菌株是导致白及叶枯病的病原菌,其为一种新的植物病原菌及国内弯孢菌属真菌的一新记录种.本研究结果为白及弯孢叶枯病的进一步研究和防控奠定了基础.

Amomum villosum, which is an important perennial medicinal plant, easily suffers from continuous cropping obstacles in the plantation. The aim of this study is to find an effective method to solve the problem of A. villosum continuous cropping. In this study, we analyzed four fields in which A. villosum was continuously cropped and a fallow field to reveal the effects of continuous cropping on the rhizosphere soil physicochemical properties, enzyme activities, and bacterial and fungal communities. Most of the soil nutrient contents gradually increased as the number of years of continuous cropping increased, whereas the soil pH decreased slightly. The soil urease and acid phosphatase activities tended to increase as the length of the continuous cropping period increased, which may have accelerated the conversion of soil substances. Furthermore, the alpha diversity of the bacterial and fungal communities decreased as the duration of the continuous cropping period increased. Additionally, the redundancy analysis revealed that bacterial and fungal community structures at the phylum level were the most correlated with pH value and catalase activity, respectively. This study may be useful for promoting the continuous cropping and sustainable development of A. villosum.

砂仁是重要南药品种之一,在我国西南和华南地区广泛种植,而生产上种源混杂严重影响产量和品质.为了解砂仁资源‘湛砂11’的形态和品质特性,更好地对砂仁种质资源进行保护和利用,通过测定‘湛砂11’的株高、叶片数、花序长度、果实大小、单果重等形态指标,以及种子团挥发油含量,挥发油中乙酸龙脑酯、樟脑和龙脑等含量的品质指标,分析其形态特征和品质特性.结果表明,‘湛砂11’的株高和叶片数显著高于对照,分别比对照增加7.85％和23.04％;叶片长度无明显差异,叶宽显著增加,外侧叶面平行于主脉的突起线较明显;叶舌棕红色、长0.53 mm,比对照显著长23.26％.花序长度显著低于对照,小花数量与对照无显著差异;小花梗长、苞片、花萼和花冠管都显著短于对照.果实近圆形,单果重比对照轻21.40％;果实种子数平均46.7粒,千粒重9.24 g,分别比对照少17.64％、轻20.35％.种子团挥发油含量3.30％,其中乙酸龙脑酯含量明显高于对照;挥发油组分在不同材料中存在特异性,‘湛砂11’共检测出16种物质,与对照品种共有12种物质,另4种物质对照品种未检出.由此可知,‘湛砂11’的植株、花、果实和种子形态特征明显,挥发油含量及成分特异,可作为优良材料重点培育.研究结果可为砂仁生产中亲本选配及品种更新和选育提供一定的理论依据.