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苜蓿假盘菌及其生物学特性研究 总被引：15，自引：3，他引：15
研究了苜蓿假盘菌及其生物学特性 ,用常规方法分离培养苜蓿假盘菌较困难 ,试验应用离心稀释分离法获得纯菌株。培养基为V-8碳酸钙琼脂培养基 ,适宜子囊孢子萌发和菌落生长的pH为 3～8和 4～6(最适为5)。在人工培养基上病菌生长缓慢 ,生长 40d的菌落直径只有 2.5～3.5mm ,在培养基上经过20d后才能形成成熟的子囊盘。苜蓿假盘菌子囊孢子萌发温度为 6～25℃ ,最适温度为 15～20℃。芽管生长温度为 10～30℃ ,最适温度为20℃。不同菌株间致病力存在显著差异(p<0.05)。 相似文献
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尖孢镰刀菌的分离鉴定及不同苜蓿品种芽期抗病性 总被引：1，自引：0，他引：1
为了解黑龙江省大庆市苜蓿根腐病的病原,评价不同苜蓿品种芽期对根腐病的抗病性,于2018年采集疑似感染根腐病的苜蓿病株,对其进行了病原分离与鉴定。将鉴定得到的致病菌接种于18个品种的紫花苜蓿幼芽,测定相对根长、相对苗长、发病率和病情指数,利用隶属函数进行抗病性综合评价。形态学和rDNA-ITS序列分析结果表明,分离获得的致病菌为尖孢镰刀菌Fusarium oxysporum,其对不同苜蓿品种芽期相对根长、相对苗长、发病率和病情指数均有显著影响(P0.05)。说明尖孢镰刀菌对苜蓿有较强致病性。抗病性综合评价表明:不同苜蓿品种芽期对尖孢镰刀菌根腐病抗性由强到弱依次为:‘龙牧801’‘斯贝德’‘SK3010’‘巨能-CR’‘肇东’‘DS310FY’‘WL168HQ’‘WL354HQ’‘TG4’‘WL319HQ’‘擎天柱’‘WL298HQ’‘龙牧806’‘北极星’‘皇后’‘北极熊’‘CW2000’‘敖汉’。 相似文献
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为探究自噬在核盘菌Sclerotinia sclerotiorum致病过程中的作用,利用酵母Saccharomyces自噬相关基因（autophagy-related gene,ATG）编码的蛋白序列比对核盘菌基因组,获得核盘菌假定ATG,并以核盘菌1980菌株为出发菌株,基于同源重组的原理对假定ATG进行敲除和回补,并测定不同突变体的生长表型和致病能力。结果表明,从核盘菌基因组中比对到2个ATG,分别命名为SsATG5和SsATG8,两者在核盘菌致病过程中均上调表达。SsATG5和SsATG8敲除突变体在菌丝生长、产草酸和侵染垫形成方面与野生型菌株无明显差异,但SsATG5敲除突变体在离体拟南芥Arabidopsis thaliana叶片上的致病力显著下降了约40%,在活体拟南芥植株上的致病力显著下降了约80%,同时SsATG5回补突变体恢复了正常的致病力。表明SsATG5参与了核盘菌的致病过程,证实自噬在核盘菌致病过程中发挥着重要作用。 相似文献
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不同核盘菌菌株及其近缘种的RAPD分析 总被引：10，自引：1，他引：9
本文利用随机引物扩增多态性DNA (RAPD)技术分析了7个生物学性状差异较大核盘菌(Sclerotinia sclerotiorum)的遗传多样性,并同三叶草核盘菌(S.trifoliorum)、小核盘菌(S.minor)的代表性菌株和莴苣上的一种产菌核病原菌的代表菌株Let-19进行了比较。结果表明40个引物中8个引物能稳定地从供试菌株中扩增出多态性DNA片段。通过分析这些多态性片段可以看出7个供试核盘菌菌株之间的遗传相似系数变化幅度为0.505 2~0.793 1,而核盘菌、三叶草核盘菌,小核盘菌和Let-19之间的遗传相似系数的变幅则为0.194 2~0.385 3。莴苣上的菌株Let-19的RA PD图谱同供试其它种的菌株既存在明显差异的DNA片段电泳带,又显示出一些位置一致的DNA片段电泳带。因而Let-19同核盘菌属真菌的亲缘关系较近。供试的引物中OPL14既能介导从供试的7个核盘菌菌株和3个近缘种的3个菌株的DNA样品中扩增出相同的DNA片段,又能扩增出种或菌株特异性DNA片段。因而RAPD技术适于研究核盘菌的遗传多样性及分析核盘菌属真菌的亲缘关系。 相似文献
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为明确挥发性化合物2-甲基苯并噻唑（2-methylbenzothiazole,2-MBTH）对向日葵菌核病病原菌核盘菌Sclerotinia sclerotiorum和番茄灰霉病病原菌灰葡萄孢Botrytis cinerea的防治潜力,采用密封盘菌丝生长速率法测定其对2种病原菌的抑制作用,利用离体叶片接种试验分析其对2种病原菌致病力的影响。结果显示,2-MBTH对核盘菌和灰葡萄孢具有明显的抑制作用,2-MBTH对核盘菌菌丝的EC50为0.87 μL/L,对灰葡萄孢菌丝的EC50为4.49 μL/L。2-MBTH能够显著降低灰葡萄孢的致病力,受抑制程度与2-MBTH浓度呈正相关;扫描电镜观察发现,2-MBTH能够使灰葡萄孢菌丝形态异常,菌丝干瘪,分枝增多,表面塌陷;使核盘菌菌丝破损,表面塌陷。另外,随着2-MBTH熏蒸浓度的增大,核盘菌的菌核数量和质量都有所减少,且健康菌核在2-MBTH的熏蒸作用下失去了萌发能力。表明2-MBTH对核盘菌和灰葡萄孢均有较高的抑制作用,表现为菌丝生长、菌核萌发受到抑制,利用其熏蒸作用可以为向日葵菌核病和番茄灰霉病的有效防控提供新思路。 相似文献
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半裸镰孢致病性及苜蓿品种间的抗病性研究 总被引：2，自引：0，他引：2
为探明半裸镰孢对接种后苜蓿种苗的致病性、筛选抗苜蓿根腐病的品种,本研究把4个来源地的9个半裸镰孢分离物接种于14个品种的紫花苜蓿种子,在接种后第14 d测定苜蓿幼苗的相对根长、相对苗高、相对发芽率和病情指数,评价不同苜蓿品种对半裸镰孢的抗病性及病原菌对苜蓿幼苗致病性的相互关系。结果表明:半裸镰孢菌株和苜蓿品种对相对根长、相对苗高、相对发芽率及病情指数均有显著的影响(P<0.05)。病原菌方面,从苜蓿品种THG-1中分离出来的半裸镰孢的致病性最强,从Aohan中分离出来的半裸镰孢的致病性最弱,从WL-323HQ、Sitel和Siriver中分离出来的半裸镰孢的致病性较强,从Reindeer、Legacy和LM400中分离出来的半裸镰孢的致病性较弱;苜蓿品种方面,Algonguin的抗病性最强,Phabulous的抗病性最弱,Verna、Victoria、Hunter river和Amerimultileaf的抗病性较强,WL-323HQ、Sanditi、Sandy和Amerilea721的抗病性较弱。 相似文献
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Zhiyuan Lv Ziwen He Jianglian Yuan Lijuan Hao Zhiguang Song Guokang Chen Jiequn Ren Ningjia He 《Plant pathology》2022,71(3):684-695
Mulberry sclerotial disease is a destructive disease that afflicts mulberry fruits throughout the world. In recent years, the impact of mulberry sclerotial disease has increased with the development of the mulberry fruit industry. Ciboria carunculoides, C. shiraiana, and Scleromitrula shiraiana are all pathogens causing mulberry sclerotial disease, but the dominant pathogen may be different in different mulberry planting areas. In this study, we investigated the causal agents of mulberry sclerotial disease in Chongqing and Sichuan, the main mulberry planting areas in south-west China. The results showed that C. carunculoides was the dominant pathogen in the investigated areas, and the disease incidence rate on some widely cultivated mulberry varieties exceeded 90%. Based on the differences in internal transcriber spacer sequences of different pathogens, we developed a method using cleaved amplified polymorphic sequences (CAPS) from digestion with the three restriction enzymes HindIII, EcoRI, and MluI for rapid detection of pathogens on mulberry fruits. Use of this method confirmed that the diseased fruits of some mulberry varieties were infected by a mixture of C. carunculoides and S. shiraiana. Long-fruit mulberry, which was considered to be resistant to sclerotial disease in the past, was also infected by C. carunculoides. Diseased fruit infected by C. shiraiana or by S. shiraiana alone were not detected. Our results suggest that C. carunculoides is probably the dominant pathogen causing mulberry sclerotial disease in south-west China. The CAPS method for rapid detection of pathogens could assist diagnosis, epidemiology, and disease monitoring. 相似文献
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Cong-Hao Wang Wen-Jing Shang Qiang Wang San-Hong Fan Krishna V. Subbarao Xiang-Ming Xu Xiao-Ping Hu 《Plant pathology》2021,70(9):2034-2045
American ginseng (Panax quinquefolius), one of the most well-known araliaceous perennial herbs, suffered from root rots and mortality in 2020 in Taibai County, Shaanxi Province, China, leading to 40%–60% yield losses. The diseased plants initially showed unevenly yellowing foliage, and yellow-brownish, water-soaked roots with internal softening. Subsequently, white fluffy mycelia manifested on the surface of diseased P. quinquefolius roots, followed by the appearance of black irregular sclerotia-like bodies. In this study, a fungal isolate (SS-TB, GenBank no. MT830866) was obtained from the infected roots. Based on the culture morphology, pathogenicity tests and phylogenetic analysis of the internal transcribed spacer (ITS) region, this isolate was identified as Sclerotinia nivalis. The optimum temperature for mycelial growth and sclerotial production was 20 ℃ and 15 ℃, respectively; the optimum pH for mycelial growth and sclerotial production was pH 6.0. This isolate grew faster and produced more sclerotia on potato dextrose agar than on other media. It infected ginseng roots with or without wounds, but inoculation of wounded roots led to more severe disease. S. nivalis also infected 43 of the 48 plant species tested, including vegetables, fruits, oil crops, and flowering plants from Fabaceae, Asteraceae, Solanaceae, Cucurbitaceae, Brassicaceae, Apiaceae, Rosaceae, Liliaceae, Chenopodiaceae, and Orchidaceae. It was nonpathogenic on Triticum aestivum, Zea mays, Anemone vitifolia, Ipomoea batatas, and Vaccinium sp. This study is the first report of S. nivalis causing white rot on P. quinquefolius. 相似文献
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Atri Ashlesha Cheema Harpreet Kaur Singh Narinder 《European journal of plant pathology / European Foundation for Plant Pathology》2021,160(3):649-662
Stem rot, incited by Sclerotinia trifoliorum Eriksson is one of the most devastating soil borne fungal pathogens of berseem (Trifolium alexandrinum L.) inflicting significant fodder and seed yield losses. Eleven plant extracts, six organic inputs, one elicitor and five organic and inorganic salts were assayed for their effectiveness against S. trifoliorum under in vitro conditions. Extracts of Aegle marmelos and Cymbopogan citrates showed complete mycelial inhibition of S. trifoliorum at 5% concentration. Among organic inputs, panchgavya and fermented cow urine recorded 100% inhibition to mycelial growth of stem rot pathogen at 10% concentration. Elicitor (chitosan) and salts namely copper sulphate and potassium carbonate provided complete mycelial inhibition of test pathogen under in vitro conditions at 0.1, 2.0 and 5.0% concentrations, respectively. The plant extracts, organic inputs and salts that exhibited highest mycelial inhibition to S. trifoliorum under in vitro conditions were evaluated for their antifungal efficacy under greenhouse and field experiments during rabi 2017–18 and 2018–19. The extracts of chitosan (78.58; 77.15%), panchgavya (75.99; 67.14%), copper sulphate 71.38; 61.18%) and A. marmelos (71.75; 56.24%) have recorded highest percent disease control as compared to untreated control in greenhouse and field trials in rabi 2017–18 and 2018–19, respectively. Significant increase in green fodder yield of berseem from 9.87 to 33.38% was also recorded after treatment with plant extracts, organic inputs and some salts. The current study showed that plant extracts, organic inputs and salts have potential for the management of stem rot of berseem.
相似文献14.
Integrated control of soil-borne plant pathogens such as Sclerotinia sclerotiorum is becoming more important as the soil fumigant methyl bromide is being phased out of use. Two alternative methods of control
that have been found to reduce viability of sclerotia are steam sterilisation (pasteurisation) of soil or the application
of the mycoparasite Coniothyrium minitans. This work investigated the possibility of integrating these two control measures. Soil was pasteurised in an autoclave,
using a temperature of 80 °C for 3 min to simulate the possible temperatures reached by soil steaming machines for field use.
Coniothyrium minitans was subsequently applied to the pasteurised soil to assess the effects of the combination of control measures in reducing
sclerotial viability of S. sclerotiorum. Similar results were found in two soil types. Either method used individually was effective in decreasing the number of
viable sclerotia, but no further reduction in sclerotial viability was seen when the two methods were combined. Coniothyrium minitans was found to colonise pasteurised sclerotia significantly quicker than untreated sclerotia, and it was seen that there was
an increase in number of C. minitans in pasteurised soil in the presence of sclerotia. Experiments were also conducted to investigate the effect of application
timing of the biocontrol agent to soil following pasteurisation, in relation to sclerotial infection. Here, two different
isolates of S. sclerotiorum were used, with similar results. Application of C. minitans to soil immediately following pasteurisation resulted in sclerotial infection by the mycoparasite, but application 7 days
or more after soil pasteurisation resulted in low recovery of the biocontrol agent from sclerotia, possibly due to the mycoparasite
being masked by the presence of other fungi which colonised the sclerotia first. 相似文献
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为明确6个苜蓿品种对苜蓿蚜Aphis craccivora的抗性差异机理,观察苜蓿蚜在不同苜蓿品种植株上的取食选择行为,利用刺吸电位（electrical penetration graph,EPG）技术判定取食过程中所出现的波形,并筛选适宜参数作为对不同苜蓿品种抗蚜性的评价指标。结果表明,苜蓿蚜在取食苜蓿时呈现出Np、Pd、A、B、C、E1、E2和F波共8种波形。苜蓿的抗虫位点主要存在于苜蓿植株的表皮、叶肉和韧皮部,当苜蓿蚜开始取食时,中苜2号的抗虫位点在叶表面,但抗性较弱,第1次刺探的发生时间迟,为16.00 min,E2波的总持续时间长,为26.99 min;赛迪7的抗虫位点集中在叶肉和韧皮部且抗性强,E2波的持续时间短,为5.00 min;金皇后的抗虫位点出现在第1个E2波之后,第1次E2波后的E1波个数为7.78个,即韧皮部的抗性最强。苜蓿蚜在不同苜蓿品种上的取食行为各异,且不同品种的抗虫位点和抗虫机制不同。聚类分析结果显示,6个苜蓿品种对苜蓿蚜的抗性存在差异,其中赛迪7的抗性最强,中苜2号的抗性较弱。 相似文献
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Single and combined colonization of Sclerotinia sclerotiorum sclerotia by the fungal mycoparasites Coniothyrium minitans and Microsphaeropsis ochracea 
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下载免费PDF全文 Potential enhancement of mycoparasitic efficacy of Coniothyrium minitans and Microsphaeropsis ochracea through concomitant colonization of Sclerotinia sclerotiorum sclerotia was investigated, following observation that the two mycoparasites did not exhibit any mutual antagonism in dual culture assays. Simultaneous application of both mycoparasites increased sclerotia mortality in a temperature range from 16 to 26°C compared to single application, indicating a predominantly additive interaction. With increasing temperature the efficacy of M. ochracea decreased, but C. minitans was unaffected. Degradation of sclerotia by C. minitans proceeded slightly faster than with M. ochracea. Simultaneous colonization of sclerotia was studied at the histopathological level with mycoparasite strains transformed via Agrobacterium tumefaciens‐mediated transformation (ATMT) with reporter genes encoding for DsRed and GFP. Sclerotia colonization followed by fluorescence microscopy revealed effective penetration of the sclerotial rind, growth and formation of pycnidia in the cortex and medulla by both antagonists, resulting in complete degradation of sclerotia within 25 days after single inoculation. Upon simultaneous inoculation, both antagonists concomitantly colonized the sclerotial tissue and independently formed pycnidia in the sclerotial medulla and on the sclerotial rind, demonstrating their ability to co‐colonize the same host fungus. Although the individual growth of the two mycoparasites in dual inoculations was slightly delayed, the sclerotia degrading effects were additive, suggesting a complementary antagonistic interaction. The combined application of two different species of mycoparasites cooperating on the same host fungus and differing in temperature requirements may be advantageous for making biocontrol applications in the field less sensitive to varying environmental and host conditions. 相似文献
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Resistance to a highly aggressive isolate of Sclerotinia sclerotiorum in a Brassica napus diversity set 下载免费PDF全文
下载免费PDF全文 Sclerotinia stem rot (SSR) of oilseed rape (OSR, Brassica napus), caused by Sclerotinia sclerotiorum, is a serious problem in the UK and worldwide. As fungicide‐based control approaches are not always reliable, identifying host resistance is a desirable and sustainable approach to disease management. This research initially examined the aggressiveness of 18 Sclerotinia isolates (17 S. sclerotiorum, one S. subarctica) on cultivated representatives of B. rapa, B. oleracea and B. napus using a young plant test. Significant differences were observed between isolates and susceptibility of the brassica crop types, with B. rapa being the most susceptible. Sclerotinia sclerotiorum isolates from crop hosts were more aggressive than those from wild buttercup (Ranunculus acris). Sclerotinia sclerotiorum isolates P7 (pea) and DG4 (buttercup), identified as ‘aggressive’ and ‘weakly aggressive’, respectively, were used to screen 96 B. napus lines for SSR resistance in a young plant test. A subset of 20 lines was further evaluated using the same test and also in a stem inoculation test on flowering plants. A high level of SSR resistance was observed for five lines and, although there was some variability between tests, one winter OSR (line 3, Czech Republic) and one rape kale (line 83, UK) demonstrated consistent resistance. Additionally, one swede (line 69, Norway) showed an outstanding level of resistance in the stem test. Resistant lines also had fewer sclerotia forming in stems. New pre‐breeding material for the production of SSR resistant OSR cultivars relevant to conditions in the UK and Europe has therefore been identified. 相似文献
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通过室内萌发试验,以80份引进紫花苜蓿主推品种为材料,研究1.2% NaCl处理对紫花苜蓿萌发期根长、芽长、发芽指数、发芽率、发芽势、活力指数及根芽比的影响。采用主成分分析、隶属函数及聚类分析相结合的方法,对紫花苜蓿萌发期的耐盐性开展综合性评价。结果表明：盐胁迫极显著影响紫花苜蓿的发芽势、发芽率和发芽指数（P<0.01）,不同品种间的变异系数介于0.008～0.723。两个主成分的累计贡献率为73.922%。发芽势与根芽比可作为紫花苜蓿萌发期耐盐性筛选的主要评价指标。聚类分析结果将80份紫花苜蓿品种划分为5个级别,其中强耐盐级别包括9份品种;较强耐盐级别包括14份品种;中等耐盐级别包括43份品种;弱耐盐级别包括13份品种;最弱耐盐级别包括1份品种。在此基础上,筛选出萌发期强耐盐级别紫花苜蓿品种为：WL168HQ、游客、天马、迪特、巨能801和巨能995。 相似文献
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Sclerotinia trifoliorum, an important pathogen of cool season legumes, displays both homothallism and heterothallism in its life cycle, unique among members of the genus Sclerotinia. Very little is known about its genetic diversity and population structure. A sample of 129 isolates of S. trifoliorum from diseased chickpea in California was investigated for genetic diversity, population differentiation and reproductive mode. Genetic diversity was estimated using mycelial compatibility (MCG) phenotypes, rDNA intron variation, and allelic diversity at seven microsatellite loci. Genetic analysis revealed high levels of genotypic diversity demonstrated by high genotypic richness (0·88). Similarly, high levels of gene diversity (mean expected heterozygosity HE = 0·68) were observed at the microsatellite loci. Geographic populations of S. trifoliorum were highly admixed as evident from low FST values (0–0·11), suggesting high contemporary or historical gene flow. Hierarchical analysis of molecular variance showed that more than 92% of the genetic variation occurred among isolates within populations. Bayesian clustering analysis identified four cryptic genetic populations that were not correlated to geographic location, and index of multilocus association was non‐significant in each of the four genetic populations. However, the presence of identical haplotypes within and among populations indicates clonal reproduction. The high levels of haplotype diversity and population heterogeneity, a lack of correspondence between MCG and microsatellite haplotype, and low levels of population differentiation suggest that populations of S. trifoliorum in chickpea have been undergoing extensive outcrossing and migration events probably shaped by human‐mediated dissemination, the underlying diverse cropping systems, and chickpea disease management practices. 相似文献
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The effects ofSclerotinia sclerotiorum live and autoclaved sclerotia, and sclerotial exudates, and commercial oxalic acid were testedin vitro on sevenConiothyrium minitans strains differing in aggressiveness towardsS. sclerotiorum. Only sclerotial exudates and autoclaved sclerotia affected the mycelial growth rate of almost all the strains tested, whereas
a change in theC. minitans mycelial growth pattern was observed in the presence of autoclaved sclerotia and live sclerotia germinating by the myceliogenic
eruptive germination. In addition, sclerotial exudates had a stimulatory effect on spore germination. These findings indicate
that the various treatments could influence theC. minitans strains regardless of their aggressiveness. 相似文献