E3 ubiquitin ligase PbrATL18 is a positive factor in pear resistance to drought and Colletotrichum fructicola infection

The Arabidopsis Toxicos en Levadura(ATL)protein is a subfamily of the E3 ubiquitin ligases,which exists widely in plants and is extensively involved in plant growth and development.Although the ATL family has been identified in other species,such as Arabidopsis,Oryza sativa,and grapevine,few reports on pear ATL gene families have been reported.In this study,92 PbrATL genes were identified and analyzed from the Pyrus breschneideri genome.Motif analysis and phylogenetic tree generation divided them into nine subgroups,and chromosome localization analysis showed that the 92 PbrATL genes were distributed in 16 of 17 pear chromosomes.Transcriptome data and quantitative real-time polymerase chain reaction(qRT-PCR)experiments demonstrated that PbrATL18,PbrATL41,and PbrATL88 were involved in both pear drought resistance and Colletotrichum fructicola infection.In addition,Arabidopsis thaliana overexpressing PbrATL18 showed greater resistance to drought stress than the wild type(WT),and PbrATL18-silenced pear seedlings showed greater sensitivity to drought and C.fructicola infection than the controls.PbrATL18 regulated plant resistance by regulating chitinase(CHI),phenylalanine ammonia-lyase(PAL),polyphenol oxidase(PPO),catalase(CAT),peroxidase(POD),and superoxide dismutase(SOD)activities.This study provided a reference for further exploring the functions of the PbrATL gene in drought resistance and C.fructicola infection.

Early Detection of Colletotrichum Kahawae Disease in Coffee Cherry Based on Computer Vision Techniques

Colletotrichum kahawae(Coffee Berry Disease)spreads through spores that can be carried by wind,rain,and insects affecting coffee plantations,and causes 80%yield losses and poor-quality coffee beans.The deadly disease is hard to control because wind,rain,and insects carry spores.Colombian researchers utilized a deep learning system to identify CBD in coffee cherries at three growth stages and classify photographs of infected and uninfected cherries with 93%accuracy using a random forest method.If the dataset is too small and noisy,the algorithm may not learn data patterns and generate accurate predictions.To overcome the existing challenge,early detection of Colletotrichum Kahawae disease in coffee cherries requires automated processes,prompt recognition,and accurate classifications.The proposed methodology selects CBD image datasets through four different stages for training and testing.XGBoost to train a model on datasets of coffee berries,with each image labeled as healthy or diseased.Once themodel is trained,SHAP algorithmto figure out which features were essential formaking predictions with the proposed model.Some of these characteristics were the cherry’s colour,whether it had spots or other damage,and how big the Lesions were.Virtual inception is important for classification to virtualize the relationship between the colour of the berry is correlated with the presence of disease.To evaluate themodel’s performance andmitigate excess fitting,a 10-fold cross-validation approach is employed.This involves partitioning the dataset into ten subsets,training the model on each subset,and evaluating its performance.In comparison to other contemporary methodologies,the model put forth achieved an accuracy of 98.56%.

油茶大小年形成的微生物基础及效应微生物Colletotrichum spinosum的应用

通过对大小年油茶根际土进行宏基因组测序,探讨了油茶大、小年根际土壤微生物群落的多样性与组成。结果显示:小年油茶根际微生物群落的多样性显著大于大年,油茶根际土优势种主要来自Proteobacteria和Basidiomycota,差异菌门主要属于Firmicutes,Candidatus,Basidiomycota和Ascomycota。功能预测表明,差异微生物主要参与碳水化合物的运输代谢、次生代谢产物的生物合成等。在此基础上,通过田间试验还鉴定到一株高度响应大小年变化的微生物菌株(Colletotrichum spinosum),该菌株可分离培养,生长速度快,属于重点差异菌门Ascomycota,且在大年的丰度显著高于小年,具有潜在提升油茶产量的应用价值。在对油茶接种Colletotrichum spinosum后,其产量显著提高,其中单株大、中、小果重分别较对照组显著提高5.48、1.39、1.87倍,而内源激素赤霉素(GA)和钾元素含量分别较对照组显著提高1.2、1.73倍。探讨了大小年油茶对根际微生物的影响,并且筛选得到了一株能够显著改善油茶田间产量的真菌Colletotrichum spinosum,为探索油茶大小年的成因提供了微生物组学层面的理论支撑。

一种山茶刺盘孢Colletotrichum camelliae实时荧光定量PCR快速检测方法的建立

【目的】建立一种快速检测茶树炭疽病病原菌山茶刺盘孢(Colletotrichumcamelliae)的实时荧光定量PCR检测方法。【方法】以茶树炭疽病病原菌山茶刺盘孢(C. camelliae)为检测目标,根据刺盘孢属ApMat基因片段设计特异性引物,建立q PCR检测技术体系,验证引物特异性,测试反应的灵敏度,绘制标准曲线,并采集田间病叶测试检测效果。【结果】设计的四组引物对中,引物对CcF/CcR特异性最好,扩增效率最高;用于定量检测C. camelliae的灵敏度为10 pg/μL,DNA浓度的对数(X)与Ct值(Y)之间的线性关系为Y=-3.529 6X+36.938(R^(2)=0.9957,E=92.01);该体系检测C.camelliae溶解曲线对应的特异峰值Tm为(85.5±0.5)℃;用该体系在人工接种C. camelliae的病斑组织和田间病叶中检测到了C. camelliae的存在。【结论】建立的q PCR反应体系可特异性定量检测C. camelliae,并可应用于田间病害的早期诊断。

Resistance risk and molecular mechanism associated with resistance to picoxystrobin in Colletotrichum truncatum and Colletotrichum gloeosporioides

Anthracnose,caused by Colletotrichum truncatum and C.gloeosporioides,is amongst the most serious diseases of soybean in China.Picoxystrobin,a quinone outside inhibitor fungicide,is commonly used for the control of anthracnose.Its resistance risk and mechanism in C.truncatum and C.gloeosporioides are unclear.In this study,the sensitivities of 128 C.truncatum and 121 C.gloeosporioides isolates to picoxystrobin were investigated,and unimodal distributions were observed with average EC_(50)values of 0.7740 and 1.1561μg mL^(-1),respectively.Eleven picoxystrobin-resistant mutants of C.truncatum and six mutants of C.gloeosporioides were acquired,with EC_(50)values varying from 5.40-152.96 and 13.53-28.30μg mL^(-1),respectively.Compared to the parental isolates,mutants showed similar or higher relative fitness in conidial production and germination,and pathogenicity.Collectively,the resistance risk of C.truncatum and C.gloeosporioides to picoxystrobin is moderate to high.There was positive cross-resistance between picoxystrobin and pyraclostrobin,but not between picoxystrobin and fluazinam,difenoconazole,or propiconazole.The G143S mutation in Cyt b protein was detected in seven high-resistant mutants of C.truncatum(RF>100),and G137R occurred in four moderate-resistant mutants(RF<_(50)).Contrastingly,there were no point mutations in Cyt b of any C.gloeosporioides mutants.Molecular docking confirmed that two mutations conferred different resistance levels to picoxystrobin.Under greenhouse trials,picoxystrobin did not control mutants with the G143S mutation,those bearing G137R or no point mutation were somewhat controlled,but at a lower level compared to wild-type isolates.These results showed that integrated management strategies should be implemented to preserve fungicide effectiveness.

辣椒炭疽病菌Colletotrichum nigrum鉴定、生物学特性及药剂敏感性研究

对2021年9—10月从吉林省和内蒙古自治区东部辣椒主产区采集的辣椒果实炭疽病样本进行病菌的组织分离和纯化,获得212株形态特征基本一致的菌株,对代表菌株进行柯氏验证,证明其具有致病性,为该病害的病原菌。结果表明,结合病原菌的形态学特征及基于ITS、TUB2、ACT、GAPDH和CHS-1基因序列构建系统发育树,确定病原菌为Colletotrichum nigrum。病原菌的生物学特性研究发现,OA培养基适合病原菌菌丝生长;D-麦芽糖是最佳碳源;蛋白胨为最佳氮源;最佳pH为10;最适培养温度为20℃;全黑暗时最适合菌丝生长。代表菌株对25种杀菌剂敏感性研究表明,400 g·L^(-1)氯氟醚·吡唑酯SC、240 g·L^(-1)氯氟醚·吡唑酯EC、42.4%唑醚·氟酰胺SC、40%唑醚·戊唑醇SC、43%唑醚·氟酰胺SC对病菌菌丝生长速率和孢子萌发均有明显抑制作用,其EC_(50)<1 mg·L^(-1),可作为该病害防治的优选药剂。

Antifungal Activity of Poncirus trifoliata Roots against Colletotrichum Species

Fruits and vegetables are an essential part of a healthy diet, providing humans with vitamins, phytonutrients, and minerals. They are significantly vulnerable, however, to post-harvest diseases caused by numerous fungal and bacterial pathogens. These pathogens can cause significant quantitative and qualitative losses from harvest to consumption during the handling and storage processes. Chemical fungicides are commonly used but are likely to leave residues on the produce, rendering short shelf-life produce, such as berries, unsuitable for human consumption. Identifying eco-friendly methods to control post-harvest disease is, therefore, of utmost importance. The presence of antifungal constituents in the roots of Poncirus trifoliata extracts was detected by thin layer chromatography-based bioautography. The active constituents were isolated and identified by bioautography assay-guided fractionation using flash chromatography followed by spectroscopic techniques. In this study, xanthoxyletin, demethylsuberosin, dentatin, nordentatin, ponfolin, and clausarin were isolated from the root extracts. The antifungal activity of these compounds was moderate to weak compared to the commercial fungicide captan. This study reports the isolation and identification of natural compounds from Poncirus trifoliata that exhibited antifungal activity against Colletotrichum fragariae and Botrytis cinerea, two major post-harvest pathogens.

Influence of Colletotrichum truncatum on the Physiological and Chemical Quality in Different Varieties of Soy Seed

The literature highlights that a severe infection by the fungus Colletotrichum truncatum may be capable of inflicting considerable damage to seeds after harvest, potentially affecting their chemical composition and physiological quality. Taking into account that currently there is no categorization in terms of susceptibility and tolerance on this pathogen, the present work is presented with the main objective of “Evaluate the influence of Pathogenicity of C. truncatum on the physiological quality (germination, vigor, viability) and biochemical components in different varieties of soybean seeds (Glycine max)” most planted in the region. The work was carried out in the Agrotec laboratory, located in the Municipality of San Alberto (Alto Paraná), using a completely randomized experimental design, with AxB factorial arrangement, where A indicates ten most planted soybean varieties in the region and B with or without artificial inoculation of Colletotrichum truncatum, with twenty treatments and four repetitions. The variables evaluated were: germination, vigor, viability and chemical composition. The data were subjected to analysis of variance and the Tukey test at 5% error. The results showed a significant statistical difference, accepting the alternative hypothesis proposed “The pathogenicity of Colletotrichum truncatum influences the physiological quality (germination, vigor, viability) and biochemical components (saturated and unsaturated fatty acids) in different varieties of soybean seeds (Glycine max)”.

西瓜炭疽病菌Colletotrichum orbiculare的分子检测

【目的】探索西瓜炭疽病菌(Colletotrichum orbiculare)的分子检测技术,为西瓜、甜瓜等生长期和采后炭疽病的快速、准确鉴定和检测提供技术和方法。【方法】根据GeneBank中Colletotrichum属的24个种ITS序列,比较设计出1对引物CY1/CY2(CY1:5′-CTTTGTGAACATACCTAACC-3′;CY2:5′-GGTTTTACGGCAGGAGTG-3′);进一步利用RAPD随机引物扩增西瓜炭疽菌C.orbiculare和菜豆炭疽菌C.lindemuthianum,找出在C.orbiculare中的特异性条带,经过克隆、测序后,设计出1对SCAR引物RB/RC。【结果】引物CY1/CY2可以特异的从C.orbiculare和C.lindemuthianum菌株中扩增到1条442 bp的条带,将这2个种的炭疽菌和其它炭疽菌种以及其它真菌种分开。引物RB/RC可以特异地在C.orbiculare中扩增出1条216 bp条带,将C.orbiculare和C.lindemuthianum分开。采用2对引物组成双重PCR,将C.orbiculare进行特异性扩增,可获得442 bp和216 bp的2条特异性条带。【结论】利用上述2对引物组成双重PCR检测体系,快速鉴定C.orbiculare,并且能够直接在植物组织中将西瓜炭疽菌C.orbiculare检测出来,灵敏度可以达到1pg.μl-1。

一株马兜铃内生真菌Colletotrichum sp.代谢产物中细胞毒活性成分的研究

从马兜铃内生真菌Colletotrichum sp.的大米发酵产物中分离得到6个化合物,经波谱数据分析分别鉴定为7-hydroxy-10-oxodehydrodihydrobotrydial(1)、格链孢酚(2)、5-甲氧基格链孢酚(3)、链格孢毒素I(4)、腾毒素(5)和二氢腾毒素(6)。以上化合物均为从该菌属中首次分离得到,其中化合物1～4对肺癌细胞和乳腺癌细胞有一定的细胞毒活性。

Elicitation on Artemisinin Biosynthesis in Artemisia annua Hairy Roots by the Oligosaccharide Extract from the Endophytic Colletotrichum sp. B501

The oligosaccharide elicitor from the mycelial wall of an endophytic Colletotrichum sp. B501 promoted the production of artemisinin in Artemisia annua L. hairy root culture. When hairy roots of 22-day-old cultures (later growth phase) were exposed to the elicitor (20 mg/L) for 4 d, the maximum content of artemisinin reached 1.15 mg/g, a 64.29% increment over the control. The electron X-ray microanalysis disclosed the rapid accumulation of Ca 2+ in the elicited cortical cells of hairy root. The electronic microscope observation revealed the high electron density area in vacuole of elicited cells. During the first day of elicitation the peroxidase activity of hairy roots was improved sharply. Some cellular morphological changes including cell shrinkage, condensation of cytoplasm and nuclear fragmentation, coincident with the appearance of DNA ladders, were observed after the third day of elicitation. It was suggested that the oligosaccharide elicitor triggered the programmed cell death, which may provide the substance or chemical signal for artemisinin biosynthesis.

The Mediation of Defense Responses of Ginseng Cells to an Elicitor from Cell Walls of Colletotrichum lagerarium by Plasma Membrane NAD(P)H Oxidases

NAD(P)H oxidases were detected in suspension cultured cells of ginseng (Panax ginseng C. A. Meyer). The activities of these enzymes were induced by an elicitor (Cle) extracted from cell walls of Col-letotrichum lagerarium. In addition, Cle induced an oxidative burst and enhanced the synthesis of saponin, activity of phenylalanine ammonialyase (PAL) , accumulation of chalcone synthase (CHS) and the transcription of a hydroxyproline-rich glycoprotein gene ( hrgp ) . Pre-treatments with DPI and quinacrine (two inhibitors of mammalian neutrophil plasma membrane NADPH oxidase) for 30 min prior to Cle addition blocked the NAD(P)H oxidase activity induced by Cle. These inhibitors also inhibited the release of H2C2, the synthesis of saponin, PAL activity and CHS accumulation. Our data revealed homology between plasma membrane NAD(P)H oxidases of mammalian neutrophil cells and ginseng suspension cells. They also indicated that deactivated NAD(P)H oxidases catalysed the release of H2O2 and that H2O2 was functioning as a second messenger stimulating PAL activity, saponin synthesis and hrgp transcription. Elevations of Ca2 + and protein phos-phorylation/dephosphorylation were required for this defense process. We propose that NAD(P)H oxidases mediate the processes of Cle-induced defense responses in ginseng suspensions, and postulate the existence of a signalling cascade including extracellular Cle stimulation, activation of plasma membrane NAD(P)H oxidases, release of H2O2, and the intracellular responses of metabolism and gene transcription in ginseng suspension cells.

Isolation and Identification of Colletotrichum gloeosporioides in Pears and Its Biological Characteristics

[Objective] This study aimed to explore the biological characteristics of Col etotrichum gloeosporioides in pears. [Method] Twenty-five C. gloeosporioides strains were isolated and identified from the diseased samples. Their pathogenicity was identified by inoculating the surface of punctured pears with fungal discs. The effects of different temperatures, pH values, carbon sources and nitrogen sources on the growth of C. gloeosporioides mycelia were explored by incubating fungal discs on the center of plates. [Result] Among the twenty-five C. gloeosporioides strains, three had strong pathogenicity, and eighteen had intermediate pathogenicity, and four strains had weak pathogenicity. Those highly-pathogenic strains had darker colonies, with dense mycelia, whereas those lowly-pathogenic ones had white colonies, with sparse mycelia. Those with fast-growing colonies showed strong pathogenicity, while those with slowly-growing colonies displayed weak pathogenicity. There was no relationship between conidia yield and pathogenicity. The optimum temperature for the growth of C. gloeosporioides mycelia was 25-30 ℃, and the optimum pH was 5.0-7.0. C. gloeosporioides could make use of various carbon sources （monosaccharide and disaccharide）, inorganic and organic nitrogen sources, and the optimal carbon source and nitrogen source were sucrose and beef extract, respectively. [Conclusion] Our study benefits further understanding of C. gloeospori-oides and helps to control pear anthracnose more effectively.

Carbendazim sensitivity in populations of Colletotrichum gloeosporioides complex infecting strawberry and yams in Hubei Province of China

The ascomycete fungus Colletotrichum gloeosporioides is a devastating plant pathogen with a wide host range and worldwide distribution. Carbendazim has been widely used to control anthracnose caused by the C. gloeosporioides complex in China for more than 30 years and resistance to carbendazim has been reported in China. A total of 125 Colletotrichum isolates of strawberry and yam were collected from different geographical regions in Hubei Province, China. Approximately 52.8％ of Colletotrichum spp. isolates showed resistance to carbendazim. The isolates tested in this study belong to four species, and the frequencies of resistant isolates differed across Colletotrichum species. Resistant isolates were found in C. siamense and C. fructicola. In contrast, all isolates of C. gloeosporioides and C. aenigma were sensitive to carbendazim. Highly carbendazim-resistant isolates harbored the E198A mutation in the β-tubulin 2 （TUB2） gene, whereas moderately carbendazim-resistant isolates harbored the F200Y mutation in the TUB2 gene. Carbendazim-sensitive Colletotrichum isolates in this study were not genetically similar enough to form a separate cluster from resistant isolates. The result of this study emphasizes the importance of knowing which Colletotrichum sp. is present, when strategies for disease control are made.

橡胶树炭疽病病原菌Colletotrichum laticiphilum生物学特性研究及防治药剂筛选

对橡胶树新发现病害病原菌Colletotrichum laticiphilum的生物学特性进行初步研究并开展室内筛选防治药剂,旨在为该病害的防治提供理论依据。通过单因子变量试验,研究病原菌最适生长条件。菌丝最适生长培养基为土豆琼脂培养基,最适生长温度为26℃,最适合生长pH值为6,菌丝致死温度为50℃、10min,分生孢子致死温度为51℃、10min。该病原菌能利用多种碳源和氮源,碳源以可溶性淀粉的利用率最高,牛肉浸膏为最适氮源,在24h光照条件下更有利于菌丝生长。采用菌丝生长速率法测定室内毒力,结果表明:4种杀菌剂对病原菌的毒力存在明显差异,其中咪鲜胺和丙环唑的毒力最强,EC50分别为0.1286mg/L、0.5208mg/L。

夹竹桃叶内生真菌Colletotrichum sp. HK-08的次生代谢产物及其活性研究

本研究运用多种色谱技术从夹竹桃叶内生真菌Colletotrichum sp.HK-08中分离得到11个化合物,利用波谱学方法鉴定其结构分别为butyl 2-(4-hydroxyphenyl)acetate(1)、4-hydroxyphenethyl acetate(2)、phenethyl 2-phenylacetate(3)、phenethyl 2-(4-hydroxyphenyl)acetate(4)、4-hydroxyphenethyl 2-(2-hydroxyphenyl)acetate(5)、4-hydroxyphenethyl 2-(4-hydroxyphenyl)acetate(6)、对羟基苯甲醛(7)、2-羟基苯乙醇(8)、对羟基苯甲酸(9)、对羟基苯乙酮(10)和3a-hydroxyindoline(11)。其中化合物4、5和11为新的天然产物,化合物1~6和11为首次从Colletotrichum属真菌中分离得到。活性测试结果显示,化合物4和6表现出一定的细胞毒活性。

大豆炭疽病菌Colletotrichum chlorophyti的鉴定

从进口的乌拉圭大豆的残留茎秆上分离到一种新的大豆炭疽病菌,根据菌落形态、分生孢子形态、ITS序列及ACT序列特征以及对大豆的致病性,将其鉴定为Colletotrichum chlorophyti,这是我国口岸首次截获该菌。

多基因序列鉴定油茶炭疽病原Colletotrichum boninense新种

油茶炭疽病是中国油茶最重要的病害之一,为进一步对油茶炭疽病原进行研究,通过柯赫氏法验证,从海南澄迈和江西分宜的油茶叶上分离到有别于其它炭疽病菌的致病菌3株。菌株在PDA培养基上,菌落圆形,呈奶油色至橙黄色,菌丝生长速度为10.8-11.3 mm/d;附着胞为椭圆形,呈深褐色至棕黑色,边缘整齐,大小为（5.3±0.9）μm×（16.1±1.1）μm;分生孢子初为橘黄色,后形成黑色孢子团,大小为（14.5±2.5）μm×（5.6±1.6）μm。多基因系统发育树显示3株病原菌与博宁炭疽菌（Colletotrichum boninense）的模式株MAFF 305972聚为一个进化枝,且达到100%的置信度。结合其形态和多基因分析,结果表明：3个菌株为博宁炭疽菌（C.boninense）,是能侵染油茶树的炭疽菌种。

芒果炭疽病菌,Colletotrichum gloeosporioides的生物学特性

芒果炭疽病菌Ｃｏｌｅｔｏｔｒｉｃｈｕｍｇｌｏｅｏｓｐｏｒｉｏｉｄｅｓ的营养生长、孢子形成、孢子萌发研究表明，营养生长和孢子形成的温度范围均为７～３７℃，适温范围分别为２０～３１℃，２５～３１℃。可以生长的ｐＨ值范围很广，以ｐＨ５．０～８．０生长良好；产孢的适宜ｐＨ为３．５～４．５。红光，兰光抑制营养生长，但光照有利于产孢，以萤光的促进作用最强。分生孢子在１０～４０℃均可萌发，适温范围为２５～３１℃。附着胞形成的温度范围为１５～３５℃，最适为３０℃。在相对湿度１００％＋水膜的条件下分生孢子萌发良好。营养有利于分生孢子萌发和附着胞形成。分生孢子萌发的ｐＨ为２～１１，最适ｐＨ为３～７，附着胞形成的最适ｐＨ值为３～６。

葡萄炭疽病菌(Colletotrichum spp.)种群对多菌灵的抗药性监测

【目的】阐明江苏丘陵地区葡萄炭疽病菌(Colletotrichum spp.)种群(GG)对多菌灵的抗药性流行动态及抗性分子机制。【方法】采用区分剂量法和菌丝生长速率法分别测定GG的抗药性流行动态和敏感性;田间人工接种GG后再检测回分离菌株对药剂敏感性的方法评价GG的抗药性流行演化;药剂作用标靶基因序列分析阐明抗性分子机制。【结果】2013年和2017年GG对多菌灵的EC50均值(ρ)分别为0.528 5 mg·L-1和7.787 8 mg·L^-1。GG对多菌灵的抗性菌株比率从2013年的2.34%上升至2017年的32.21%。2017年和2018年多菌灵接种抗性菌株处理的防效分别为0.64%和4.18%。回分离GG中抗性菌株/敏感菌株的比率2017年和2018年分别为65.00%和68.18%,均高于接种比率50%。抗性菌株靶标基因(TUB2)第198位的谷氨酸突变成丙氨酸(E198A),或第200位的苯丙氨酸突变成络氨酸(F200Y)。【结论】江苏丘陵地区GG对多菌灵已形成抗药性流行。多菌灵持续施用是GG田间抗药性流行的驱动因子。GG抗性菌株标靶基因突变类型为E198A或F200Y。