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Preliminary Research on Conditions of Toxins Produced by Pestalotiopsis photiniae

JIANG Ji-Zhi,LI Xiang-Bin,GUI Chun-Shuang,WANG Yan,
,李向彬,桂春爽,王 岩

微生物学通报 , 2009,
Abstract: Pestalotiopsis photiniae is one of the predominant pathogens of strawberry root rot disease. Based on preliminary research, it was proved that crude toxins were main pathogenic substances of the pathogen. For further investigation and utilization of toxins produced by this fungus, conditions of producing toxins were analyzed with the leaf disk method in this experiment. The result showed that pH values, cultural time, vibration, and tested temperatures obviously affected the production of toxins, except for light treatment. The most suitable culture conditions for the toxin production were pH 6.2, 25°C, darkness and stillness, for 5 d~7 d. Besides, it was discovered that crude toxins could significantly inhibit seed germination and elongation growth of roots or shoots for maize, rye and mung bean.
Sensitivity among Pestalotiopsis spp. Against the Phytoalexins of Three Rosaceae Plants  [PDF]
S. M. Widyastuti
Pakistan Journal of Biological Sciences , 2001,
Abstract: The experiment was aimed to know differential sensitivity of four Pestalotiopsis spp., P. funerea (Eriobotrya japonica), Pestalotiopsis sp. (Rhaphiolepis umbellata), P. photinia (Photinia glabra) and P. breviseta (Viburnum awabuki), to the five phytoalexins isolated from three Rosaceae plants. The names of two kind biphenyl phytoalexins accumulated in E. japonica (loquat), R. umbellata and P. glabra (photinia), were aucupurin and eriobofuran, 4`-methoxyaucuparin and rhaphiolepsin, 2`-methoxyaucuparin and 4`-methoxyaucuparin, respectively. Four Pestalotiopsis spp. showed different sensitivity to the phytoalexins tested. P. funerea was less sensitive to aucuparin in comparison with the other fungi. The less sensitive fungi to eriobofuran was obtained with P. photiniae., P. breviseta was unable to germinate in the medium containing rhaphiolepsin in concentration of 10 ppm and 50 ppm. Of the five phytoalexins tested, 2`-methoxyaucuparin was less toxic to the fungi.
Molecular phylogenetic investigation on relationship of endophytic and pathogenic Pestalotiopsis species

WEI Ji-guang,XU Tong,HUANG Wei-hua,GUO Liang-dong,PAN Xiu-hu,

浙江大学学报(农业与生命科学版) , 2008,
Abstract: Isolates of endophytic and pathogenic Pestalotiopsis from Pinus massoniana,Podocarpus macrophyllus,Podocarpus nagi,Camellia japonica,Camellia sinensis and Camellia sasanqua were collected and morphologically identified.The investigation on relationship between endophytic Pestalotiopsis and pathogenic Pestalotiopsis species based on molecular phylogenetic tree of rDNA ITS sequences was carried out.It was found that Pestalotiopsis isolates of the same species no matter it was pathogenic or endophytic were clustered in the same branch of phylogenetic tree,for example,P.lawsoniae was an endophytic fungus on twigs and a pathogen on leaves of P.massoniana;P.karstenii was an endophytic fungus on twigs and a pathogen on leaves of C.japonica;P.photiniae was an endophytic fungus on twigs of C.japonica and C.sasanqua and a pathogen on leaves of P.massoniana;and P.theae was a pathogen on leaves of C.sinensis and an endophytic fungus on twigs and leaves of C.nitidissima and twigs of P.macrophyllus.The result showes that some Pestalotiopsis species could be endophytic and pathogenic states on different species or parts of plant and an endophytic Pestalotiopsis could transformed into a pathogenic Pestalotiopsis under a certain condition.The result also supportes the previous conclusion that Pestalotiopsis species are not generally specific to host plants.
Ergosterol-Induced Sesquiterpenoid Synthesis in Tobacco Cells  [PDF]
Fidele Tugizimana,Paul A. Steenkamp,Lizelle A. Piater,Ian A. Dubery
Molecules , 2012, DOI: 10.3390/molecules17021698
Abstract: Plants have the ability to continuously respond to microbial signals in their environment. One of these stimuli is a steroid from fungal membranes, ergosterol, which does not occur in plants, but acts as a pathogen-associated molecular pattern molecule to trigger defence mechanisms. Here we investigated the effect of ergosterol on the secondary metabolites in tobacco (Nicotiana tabacum) cells by profiling the induced sesquiterpenoids. Suspensions of tobacco cells were treated with different concentrations (0–1,000 nM) of ergosterol and incubated for different time periods (0–24 h). Metabolites were extracted with a selective dispersive liquid-liquid micro-extraction method. Thin layer chromatography was used as a screening method for identification of sesquiterpenoids in tobacco extracts. Liquid chromatography coupled to mass spectrometry was used for quantitative and qualitative analyses. The results showed that ergosterol triggered differential changes in the metabolome of tobacco cells, leading to variation in the biosynthesis of secondary metabolites. Metabolomic analysis through principal component analysis-scores plots revealed clusters of sample replicates for ergosterol treatments of 0, 50, 150, 300 and 1,000 nM and time-dependent variation at 0, 6, 12, 18 and 24 h. Five bicyclic sesquiterpenoid phytoalexins, capsidiol, lubimin, rishitin, solavetivone and phytuberin, were identified as being ergosterol-induced, contributing to the altered metabolome.
Diversity traits of endophytic Pestalotiopsis from pine trees in Sichuan and its control effect

- , 2015,
Abstract: 【目的】对四川松树内生拟盘多毛孢Pestalotiopsis的生态分布及其对松树病害的防治效果进行分析,为松树病害无公害治理提供理论与实践基础。【方法】对分布于四川的松树内生拟盘多毛孢的多样性进行调查统计,分析树种、松树组织、海拔和季节对内生拟盘多毛孢定殖率、Shannon-Weiner指数和相似性指数的影响。在此基础上,筛选对松落针病菌、烂皮病菌、赤枯病菌有拮抗作用的内生拟盘多毛孢,浸渍法检测其对松针的致病性,采用喷雾法和针刺法分别对室内盆栽湿地松苗接种拮抗菌和3种病原菌,计算发病率、病情指数和防治效果。【结果】湿地松、马尾松、火炬松中内生拟盘多毛孢的多样性明显高于华山松和云南松,内生拟盘多毛孢在针叶中的分布多于枝和干,其多样性在海拔较低地区(400~600 m)相对较高,不同季节则以春季多样性最高。此外,散沫拟盘多毛孢(P.lawsoniae)、小孢拟盘多毛孢(P.microspor)和石楠拟盘多毛孢(P.photiniae)对松落针病菌、松烂皮病菌、松赤枯病菌3种病原均有拮抗作用,抑制率达38.49%~77.42%,其中P.lawsoniae的作用最为明显,且在致病性测定中对松针无伤害作用。室内对湿地松苗病害的防治试验中,P.lawsoniae孢子原液及稀释液(50倍液和500倍液)对3种病害均表现出了较好的防治效果,防治效果达40.90%~89.77%。【结论】松树内生拟盘多毛孢资源丰富,对松树病害具有生物防治潜力,其中P.lawsoniae对松树落针病、烂皮病和赤枯病具有良好的生防前景。
【Objective】Ecological distribution of endophytic Pestalotiopsis from pine species in Sichuan and its control effect on pine diseases were analyzed to provide theoretical and practical basis for pollution free control of pine diseases.【Method】The diversity of endophytic Pestalotiopsis from pine species in Sichuan was investigated,and the effects of species,tissues,altitudes,and seasons on colonization rate,Shannon-Weiner index,and coefficient similarity of endophytic Pestalotiopsis were analyzed.Then,endophytic Pestalotiopsis with resistance against Lophodermium pinastri,Cenangium ferruginosum and Pestalotiopsis funereal were screened.The pathogenicity of endophytic Pestalotiopsis was determined by impregnation method.The antagonistic fungus and pathogen were inoculated in Pinus elliotii by spraying and needle-punching methods.Incidence,disease index,and control effect were also calculated.【Result】Endophytic Pestalotiopsis in Pinus elliotii,Pinus massoniana,Pinus taeda had significantly higher diversity than that in Pinus armandii and Pinus yunnanensis.Distribution of endophytic Pestalotiopsis was more in needles than in branches and stems.Highest endophytic diversity was found in low altitude (400-600 m) in spring.Endophytic P.lawsoniae,P.microspore and P.photiniae showed antagonistic effect against three tested pine pathogens (L.pinastri,C.ferruginosum and P.funereal) with inhibition rates of 38.49%-77.42%.P.lawsoniae was the most effective one without injure effect on needles in the pathogenicity determination.In the controlled experiment in laboratory,the spore stock solution and diluent solution (50 and 500 times) of P.lawsoniae had positive control effects against all three diseases with inhibition rates of 40.90%-89.77%.【Conclusion】The endophytic species of Pestalotiopsis from the pine species were rich and potentially functional against pine diseases.P.lawsoniae was a good candidate for the
A new eremophilane-type sesquiterpene from the phytopatogen fungus Lasiodiplodia theobromae (Sphaeropsidaceae)
Nunes, Fátima M.;Oliveira, Maria da Concei??o F. de;Arriaga, ?ngela M. C.;Lemos, Telma L. G.;Andrade-Neto, Manoel;Mattos, Marcos C. de;Mafezoli, Jair;Viana, Francisco M. P.;Ferreira, Viviane M.;Rodrigues-Filho, Edson;Ferreira, Ant?nio G.;
Journal of the Brazilian Chemical Society , 2008, DOI: 10.1590/S0103-50532008000300015
Abstract: the phytopatogenic fungus lasiodiplodia theobromae, isolated from guava, was cultivated in rice for 32 days at room temperature. extraction with ch2cl2:meoh (3:7), followed by chromatography fractionation of the extract provided ergosterol. from the fungus culture in czapeck medium for 40 days at room temperature, were isolated isocoumarin cis-4-hydroxymeleine and an eremophilane-type sesquiterpene. the latter compound is being reported for the first time in the literature. also, this is the first time that an eremophilane sesquiterpene is described for lasiodiplodia genus.
A New Sesquiterpenoid Hydroquinone from the Marine Sponge Dysidea arenaria  [PDF]
Yan Qiu,Xiu Min Wang
Molecules , 2008, DOI: 10.3390/molecules13061275
Abstract: Detailed chemical investigation of the South China sponge Dysidea arenaria resulted in the isolation of a new sesquiterpenoid hydroquinone, 19-hydroxypolyfibrospongol B (1), along with five known compounds: polyfibrospongol B (2), isosemnonorthoquinone (3), ilimaquinone (4), smenospongine (5) and smenotronic acid (6). The structures were determined by extensive spectroscopic analysis. The in vitro anti- HIV activity on HIV-1 RT was evaluated. Compounds 3 -6 displayed moderate inhibitory activity, with IC50 values of 239.7, 16.4, 176.1, and 130.4 μM, respectively, while 1 and 2 were found to be inactive against the same biological target.
Two novel eremophilane sesquiterpenes from an endophytic Xylariaceous fungus isolated from leaves of Cupressus lusitanica
Amaral, Luciana S.;Rodrigues-Filho, Edson;
Journal of the Brazilian Chemical Society , 2010, DOI: 10.1590/S0103-50532010000800006
Abstract: two new eremophilane sesquiterpenes, cupressolide a and cupressolide b, along with two known sesquiterpenes, has been characterized from the etoac extract of a liquid medium where a xylariaceous fungus, isolated as an endophytic fungus from health tissues of cupressus lusitanica leaves, was cultivated. the structures of the isolated compounds were determined by analyses of their ms and nmr spectroscopic data.
Comparison of the Biological Properties of Several Marine Sponge-Derived Sesquiterpenoid Quinones  [PDF]
Cherie A Motti,Marie-Lise Bourguet-Kondracki,Arlette Longeon,Jason R Doyle,Lyndon E Llewellyn,Dianne M Tapiolas,Ping Yin
Molecules , 2007, DOI: 10.3390/12071376
Abstract: Eight naturally occurring marine-sponge derived sesquiterpenoid quinones wereevaluated as potential inhibitors of pyruvate phosphate dikinase (PPDK), a C4 plantregulatory enzyme. Of these, the hydroxyquinones ilimaquinone, ethylsmenoquinone andsmenoquinone inhibited PPDK activity with IC50’s (reported with 95% confidenceintervals) of 285.4 (256.4 – 317.7), 316.2 (279.2 – 358.1) and 556.0 (505.9 – 611.0) μM,respectively, as well as being phytotoxic to the C4 plant Digitaria ciliaris. The potentialanti-inflammatory activity of these compounds, using bee venom phospholipase A2(PLA2), was also evaluated. Ethylsmenoquinone, smenospongiarine, smenospongidine andilimaquinone inhibited PLA2 activity (% inhibition of 73.2 + 4.8 at 269 μM, 61.5 + 6.1 at242 μM, 41.0 + 0.6 at 224 μM and 36.4 + 8.2 at 279 μM, respectively). SAR analysesindicate that a hydroxyquinone functionality and a short, hydroxide/alkoxide side-chain atC-20 is preferred for inhibition of PPDK activity, and that a larger amine side-chain at C-20 is tolerated for PLA2 inhibitory activity.

ZHU PEI-LIANG,GE QI-XIN,XU TONGZhejiang Agricultural University,Hangzhou,

菌物学报 , 1991,
Abstract: In the taxonomic studies of the genus Pestalotiopsis,a large number of collec- tions of Pestalotiopsis from China have been examined and identified.Following Steyaert's (1949) and Sutton's (1969,1975,1980) views,even new combinations,i.e.Pestalotiopsis carveri (Guba) comb.nov.,Pestalotiopsis clesticae (Koord.) comb.nov.,Pestalotiopsis langloisii (Gu- ba) comb.nov.,Pestalotiopsis olcandri (Guba) comb.nov.,Pestalotiopsis sinensis (Shen) comb. nov.,Pestalotiopsis sydowiana (Bres.) comb.nov.and Pestalotiopsis zahlbruckneriana (Bres.) comb.nov.are presented.
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