首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 140 毫秒
1.
桃褐腐病菌(Monilinia fructicola)对3种杀菌剂的敏感性   总被引:1,自引:0,他引:1  
采用生长速率法测定了采自北京平谷区3个桃园的125株桃褐腐病菌对甲基硫菌灵、戊唑醇和异菌脲3种杀菌剂的敏感性,发现甲基硫菌灵对桃褐腐病菌的EC50主要分布在1.0×10-5~0.2μg/mL,戊唑醇对桃褐腐病菌的EC50主要分布在0.006~0.022μg/mL之间。异菌脲对桃褐腐病菌的EC50主要分布在0.15~0.55μg/mL之间。研究结果表明,北京地区的桃褐腐病菌对这3种杀菌剂都比较敏感,未产生明显的抗药群体。建立了褐腐病菌对异菌脲抗药性的敏感基线。而且,数据分析表明:甲基硫菌灵、戊唑醇和异菌脲之间均不存在交互抗性。  相似文献   

2.
桃褐腐病菌对多菌灵抗性的AS-PCR检测技术   总被引:1,自引:0,他引:1  
罗梅  阴伟晓  罗朝喜 《植物保护》2020,46(6):136-143
由于杀菌剂的长期大量使用, 植物病原菌对杀菌剂抗性问题日趋突出, 严重影响病害防治的效果?褐腐病是一种在全世界范围内广泛发生和流行的重要果树病害?本文以桃褐腐病菌Monilinia fructicola为例, 基于已知的多菌灵抗性机理, 即靶标β微管蛋白基因TUB2的点突变E198A, 建立了一种桃褐腐病菌对多菌灵抗性的等位基因专化性PCR检测技术?结果表明, 碱基错配?内参引物?退火温度?dNTPs?Taq DNA聚合酶?专化性引物浓度及配比等因素均对检测效率有影响?经过对以上因素的优化, 并对优化后的检测技术进行专化性及灵敏度评价, 证实该检测技术能特异性地鉴别桃褐腐病菌M. fructicola对多菌灵抗性基因型E198A, 且检测灵敏度可达到4.342 pg/μL病菌DNA, 有望在实践中推广使用?  相似文献   

3.
地肤子提取物抑菌机理和超微结构观察   总被引:1,自引:0,他引:1  
为探讨地肤子甲醇萃取物经柱层析后分离得到的有效成分对桃褐腐病菌的作用机理,以桃褐腐病菌为供试菌种,对作用方式、体内酶活性以及蛋白质含量进行了测定,并在扫描电镜下对菌体的超微结构变化进行了观察。结果表明地肤子提取液对桃褐腐病菌起到了抑制作用,且随着提取液浓度的增加,桃褐腐病菌体内酶活性降低,而蛋白质的含量成增长的趋势。扫描电镜观察可看出其影响了孢子与菌丝正常生长,使其形态发生较大变化,有大量溢出物,且菌丝粗细不均一,发生断裂。即地肤子提取液通过降低桃褐腐病菌体内酶活性、增加蛋白质的含量以及破坏菌丝和孢子的正常生长来起到抑菌的作用。  相似文献   

4.
托布津是广谱内吸性杀菌剂,能防治多种作物病害,兼具预防和治疗作用。喷施后在植物体内转化成多菌灵而防治病害,防病谱与多菌灵基本相同。多菌灵的主要杀菌机理是抑制真菌的有丝分裂中纺锤体的形成,作用机制单一,故易诱致病菌产生抗药性,使防治失效。托布津、多菌灵、苯菌灵(苯来特)和噻菌灵(特克多)等药剂都属苯并咪唑类杀菌剂。因此一定要避免长期单一使用本剂或它们彼此间同时混合使用或交替使用,以防止病菌产生抗药性正交互抗药性托布津、多菌灵不可交替使用和混合使用$广西大学农学院!南宁530005@赖传雅  相似文献   

5.
BTH诱导黄瓜对霜霉病的抗性   总被引:6,自引:0,他引:6  
 由黄瓜霜霉病菌(Pseudoperonospora cubensis)引起的病害是黄瓜生产上的主要病害,利用化学药剂是当前我国菜农的主要防病措施。而频繁使用化学杀菌剂,不仅易使病菌产生抗药性,且影响环境安全和人体健康。  相似文献   

6.
桃褐腐病是桃树普遍发生的一种病害,严重影响桃树的产量和效益。介绍桃褐腐病的为害症状、发病规律及综合防治技术措施。  相似文献   

7.
杀菌剂抗性分子检测技术的研究进展   总被引:1,自引:0,他引:1  
靶标病菌基因突变是许多内吸性杀菌剂出现抗性的根本原因,检测与抗药性相关的靶标病菌基因突变对阐明抗药性发生的分子生物学机制及进行早期诊断具有重要意义。目前已成功用于检测靶标病菌抗药性菌株的分子检测技术有6种:等位基因特异性扩增、限制性片段长度多态性、等位基因特异性寡核苷酸杂交、单链构象多态性、实时定量PCR、变性高效液相色谱分析。这些技术能够快速、灵敏地检测田间早期出现的抗药性或抗药性种群的发展动态,在病害的可持续管理系统中科学使用杀菌剂方面发挥着重要作用。  相似文献   

8.
病菌的抗药性问题   总被引:1,自引:0,他引:1  
李进 《植物保护》1980,6(1):27-30
近年来由于抗菌素与内吸杀菌剂的广泛使用,病菌的抗药性问题已成为生产上的重要问题之一。 病菌的抗药性可以分为自然抗药性与获得抗药性。所谓自然抗药性就是指病菌原有对药剂的抵抗能力。因此病菌的种类不同,对药剂的抵抗能力也有差异。例如镰孢菌虽  相似文献   

9.
恶苗病是水稻生产上较为严重的种传真菌病害,咪唑类广谱内吸性杀菌剂咪鲜胺是目前防治该病害的主要药剂。以对咪鲜胺抗性及敏感的田间水稻恶苗病菌为试材,研究了其适合度及对几种常用杀菌剂的交互抗性。结果显示:抗性菌株的抗药性可稳定遗传,其温度敏感性与敏感菌株无明显差异,部分抗性菌株在菌丝生长速率、产孢量、孢子萌发率和致病力方面显著高于田间敏感菌株;咪鲜胺与三唑类及2-氰基丙烯酸酯类杀菌剂之间均无交互抗性。研究表明,对咪鲜胺产生抗性的水稻恶苗病菌具有较强的适合度,在田间自然条件下有可能形成优势群体,因此需合理轮换使用不同作用机制的杀菌剂,以延缓其抗药性的发展。  相似文献   

10.
樱桃褐腐病是樱桃生产上的一种常见病害,除为害樱桃外.还可为害桃、李、杏等核果类果树,引起花腐和果腐。该病在樱桃上主要为害果实.也可为害花和叶片。  相似文献   

11.
近年随着乡村产业调整和果业发展, 褐腐病在我国的发生呈加重趋势。本文对重庆地区核果类果树褐腐病的发生状况做了调查分析, 在室内通过平板及离体果实试验, 筛选拮抗菌和化学药剂, 为田间防治实践提供科学依据。主要结果如下:桃褐腐病在重庆普遍发生, 核果类果树均易感, 病原菌经鉴定为果生链核盘菌Monilinia fructicola; 系统调查初步分析发现, 降雨时间与李褐腐病发生发展关系最密切, 其与病情指数增幅的相关系数R=0.94(P<0.05); 平板对峙和离体桃果筛选, 获得2株有生防潜力的放线菌YLS5-2和YYDB3-1, 二者的抑菌率分别为91.3%和84.5%, 相对防效分别为65.1%和67.1%, 可能具有较好的应用前景; 平板毒力测定和离体桃果控病试验, 效果最优的化学药剂分别为戊唑醇、苯甲·丙环唑, 其中戊唑醇在推荐浓度处理96 h其离体果实防效仍维持在100%水平。  相似文献   

12.
BACKGROUND: Management of demethylation inhibitor (DMI) fungicide resistance in Monilinia fructicola (G. Winter) Honey is a priority in peach orchards of the southeastern United States, but DMI fungicides are still an important component of antiresistance strategies in view of the few effective alternatives. The goal of this study was to investigate potential benefits of a sulfur/propiconazole mixture for the control of propiconazole-resistant isolates.RESULTS: The mixture provided the best control for propiconazole-resistant isolates, regardless of protective or curative application timings, or the presence or absence of fruit injury. Propiconazole-resistant isolates developed disease on detached fruit after protective or curative applications of propiconazole or its mixture with sulfur, but protective applications of the mixture significantly reduced (P = 0.05) disease symptoms compared with the individual compounds. Additive to slightly synergistic effects were observed for the mixture in protective treatments of peaches inoculated with propiconazole-resistant isolates.CONCLUSION: The results suggest that the addition of elemental sulfur to a DMI fungicide is likely to be a relatively inexpensive means to improve brown rot control in peach production areas where reduced sensitivity to DMI fungicides is suspected but has not led to noticeable control failure.  相似文献   

13.
Field occurrence of vinclozolin resistance in Monilinia fructicola   总被引:1,自引:1,他引:0  
Strains of Monilinia fructicola resistant to vinclozolin were isolated from fruit affected by brown rot from an orchard where the fungicide had been used over four seasons. Resistant isolates were pathogenic to peach fruit, and resistance of one isolate was confirmed following dipping of inoculated fruit in fungicide suspensions. In culture, one of four resistant isolates was identical in colony morphology and sporulation to sensitive isolates from different geographic areas. The other resistant isolates produced dark mycelium on PDA and were slower growing. Vinclozolin-resistant isolates were resistant in vitro to two other dicarboximide fungicides, iprodione and procymidone.  相似文献   

14.
Demethylation inhibitor (DMI) fungicides are used to control brown rot in stone fruit worldwide. However, their specific mode of action can select resistant isolates of Monilinia fructicola. Monilinia fructicola resistant to DMI fungicides are associated with a fitness cost in the absence of selective pressure, indicating that the sensitive population can be re-established when discontinuing the fungicide in the field. This work aimed to build up the sensitive population of M. fructicola after discontinuing the use of tebuconazole for successive crop seasons. The sensitivity of M. fructicola to tebuconazole was assessed in four commercial peach orchards in Paraná and São Paulo States from 2012/13 to 2015/16. Different fungicide programmes were used and DMI fungicides were discontinued from 2013/14. The sensitivity of M. fructicola to tebuconazole was assessed by a mycelial growth assay in vitro and by determining the frequency of the G461S mutation in the MfCYP51 gene. The isolates from Paraná had high sensitivity to the fungicide across all seasons and the frequency of the G461S mutation remained below 5%. The isolates from São Paulo were highly resistant in the 2012/13 season; however, there was a gradual decline until 2015/16. In addition, the G461S mutation frequency in Sao Paulo State was about 80% in the 2012/13 season, but reduced until it was completely undetectable in 2015/16. These results provide evidence that resistance can be managed in orchards with high selective pressure to tebuconazole after discontinuing the use of the fungicide for at least 3 years.  相似文献   

15.
European Journal of Plant Pathology - A new approach to modelling epidemics of brown rot caused by Monilinia spp. in Ebro Valley peach orchards has been developed. This compartmental model was...  相似文献   

16.
Reactive oxygen species (ROS) play dual roles in plant–microbe interactions in that they can either stimulate host resistance or enhance pathogen virulence. Innate resistance in peach (Prunus persica) to the brown rot fungal pathogen Monilinia fructicola is very limited, and knowledge of the mechanism of virulence is rudimentary. In this study, production of hydrogen peroxide, a major component of ROS, was determined in peach flower petals in response to M. fructicola (a host pathogen) and Penicillium digitatum (a non‐host pathogen). Monilinia fructicola was able to infect flower petals while P. digitatum was not. During the host‐specific interaction, M. fructicola induced hydrogen peroxide accumulation in flower petals. Application of exogenous antioxidants significantly reduced hydrogen peroxide accumulation as well as the incidence of brown rot disease. Application of M. fructicola spores to the surface of intact flower petals induced gene expression and increased enzyme activity of NADPH oxidase and cell wall peroxidase in host tissues, resulting in the production of hydrogen peroxide. Petals inoculated with M. fructicola exhibited high levels of protein carbonylation and lipid peroxidation. No significant response in gene expression, enzyme activity or hydrogen peroxide levels was observed in peach flower petals treated with P. digitatum. These results suggest that M. fructicola, as with other necrotrophic fungi, uses the strong oxidative response as part of a virulence mechanism.  相似文献   

17.
BACKGROUND: The cytochrome b (Cyt b) gene is a key genetic determinant for quinone outside inhibitor (QoI) fungicide resistance in plant pathogenic fungi. A mutation at amino acid position G143 can cause qualitative resistance unless it is part of the recognition site for a self‐splicing intron. The objective of this study was to clone and sequence the Cyt b gene from Monilinia fructicola (Wint.) Honey, the causal agent of brown rot of stone fruits, and to assess the risk for the development of a mutation at position 143. RESULTS: The Cyt b gene of M. fructicola was 11 927 bp in size and contained seven introns located at cDNA positions (5′–3′) 204, 395, 430, 491, 507, 780 and 812 with sizes of 1592, 1318, 1166, 1252, 1065, 2131 and 2227 bp respectively. Sequence analysis revealed that the above‐mentioned 1166 bp intron, a self‐splicing group I intron, was located just downstream of the G143 codon. The Cyt b gene region covering the G143 location and the adjacent 1166 bp intron was PCR amplified and sequenced from Chinese and US isolates, indicating that the intron may be omnipresent in M. fructicola. CONCLUSION: This is the first complete Cyt b gene sequence published for M. fructicola or any other Monilinia species, forming the basis for molecular analysis of QoI fungicide resistance. Sequence analysis revealed that the G143A mutation responsible for high levels of QoI fungicide resistance in many plant pathogenic fungi may not develop in M. fructicola unless genotypes emerge that lack the 1166 bp intron. Copyright © 2010 Society of Chemical Industry  相似文献   

18.
 美澳型核果链核盘菌(Monilinia fructicola)引起的褐腐病是严重威胁桃生产的重要真菌性病害。为揭示该病原菌的抗药性机制和发掘新的药剂靶标,本研究利用同源重组分割标记法对MfSre1基因进行了敲除,并研究了该基因的生物学功能。与亲本甾醇14-α-脱甲基化酶抑制剂(DMI)抗性菌株Bmpc7相比,敲除转化子的菌落形态、菌丝生长速率、产孢能力和致病力没有显著变化(P>0.5),对DMIs杀菌剂的敏感性、过氧化氢和高浓度甘油渗透胁迫也没有显著性区别。但对金属离子、糖类、细胞壁/细胞膜破坏剂的敏感性明显降低,对二甲酰亚胺类杀菌剂(DCFs)的抗性水平显著上升。这些结果表明,MfSre1参与调控对部分外源渗透的胁迫和对DCFs杀菌剂的敏感性。  相似文献   

19.
ABSTRACT Visible and nonvisible quiescent infections of immature and mature fruit are an integral component of the disease cycle of brown rot of sweet cherry in California. Detection of these infections is critical for developing efficient and efficacious fungicide management programs. The previously published DNA amplification primers mfs3 and NS5 for the identification of Monilinia fructicola were very specific in amplifying DNA of M. fructicola only and not M. laxa. This primer set, however, only detected DNA from some of the California isolates of M. fructicola. This genetic diversity was supported by random amplified polymorphic DNA (RAPD) analysis. Using eight 10-mer primers, seven M. fructicola isolates from California were all identified as genetically distinct. Using the same primers, only one polymorphism was detected among seven isolates of M. laxa. The multiple genotypes identified within the small population sample of M. fructicola, but not of M. laxa, using RAPD analysis could be indicative of genetic recombination within M. fructicola but not within M. laxa. To detect early brown rot infections in fruit, two primer sets that were developed from DNA sequences of either ribosomal DNA (MF5/ITS4/ITS3) or a RAPD fragment (X-09intF3/X-09R) specifically amplified DNA from isolates of M. fructicola and Monilinia species, respectively. No amplification products were present when using DNA from Botrytis cinerea or from other fungi commonly found on sweet cherry fruit. Primers X-09intF3 and X-09R were more sensitive and reliable for detecting small amounts of target DNA either extracted from conidia or from laboratory-inoculated cherry fruit with early brown rot infections that showed no visual symptoms or with visible quiescent infections. Furthermore, these primers also were effective for detecting visible quiescent infections in cherry fruit that were collected in the field.  相似文献   

20.
BACKGROUND: Thiophanate-methyl, a member of the benzimidazole class of fungicides, is used in California to control brown rot of stone fruit caused by Monilinia fructicola (G. Wint.) Honey. The goal of this study was to develop a real-time polymerase chain reaction (PCR) assay as an efficient method to quantify the E198A allele of beta-tubulin that confers benzimidazole resistance. RESULTS: Using the real-time PCR assay, the frequency of allele E198A (FEA) in a population was determined from the quantities of DNA amplified with the E198A allele-specific primer pair HRF/HRR and the M. fructicola-specific primer pair MfF6/MfR6. The average proportions of highly resistant isolates determined with the conventional fungicide sensitivity method were within the range of average FEA values determined with the real-time PCR assay. We also determined the FEAs of M. fructicola populations sampled from 21 stone fruit orchards in California. Only one orchard showed a high FEA over 0.20, seven orchards had values between 0.01 and 0.1, and 13 orchards had values less than 0.01. CONCLUSION: The real-time PCR assay developed in this study provides a potentially useful tool to efficiently quantify benzimidazole resistance for large M. fructicola populations.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号