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1.
ABSTRACT The potential of volatile substances emitted by 'Isabella' grapes (Vitis labrusca) to control gray mold (Botrytis cinerea) on 'Hayward' kiwifruit (Actinidia deliciosa) was studied. The closed Mariotte system was used as a bioassay method to analyze quantitatively the biological action of these volatiles on B. cinerea growth. In vivo experiments compared the effects of volatiles from 'Isabella' grapes versus volatiles from 'Roditis' grapes (V. vinifera) and a B. cinerea control on the growth and disease development of B. cinerea on kiwifruit. The effect of the volatiles on the growth of B. cinerea was tested at various temperatures and times of inoculation after the wounding of kiwifruit, as well as using various weights and developmental stages of the grapes. The 'Isabella' volatiles limited the incidence of infection by reducing both the inoculum density and the activity of the pathogen. The weight and developmental stage of the grapes were important in the degree of inhibitory action of the 'Isabella' volatiles. The inhibitory action was more pronounced at 21 degrees C irrespective of the inoculation time after wounding. The study shows the potential for successful biological control of B. cinerea on kiwifruit by volatiles from 'Isabella' grapes.  相似文献   

2.
ABSTRACT Two biocontrol agents, a yeast (Pichia guilermondii) and a bacterium (Bacillus mycoides), were tested separately and together for suppression of Botrytis cinerea on strawberry leaves and plants. Scanning electron microscopy revealed significant inhibition of Botrytis cinerea conidial germination in the presence of Pichia guilermondii, whereas Bacillus mycoides caused breakage and destruction of conidia. When both biocontrol agents were applied in a mixture, conidial destruction was more severe. The modes of action of each of the biocontrol agents were elucidated and the relative quantitative contribution of each mechanism to suppression of Botrytis cinerea was estimated using multiple regression with dummy variables. The improvement in control efficacy achieved by introducing one or more mechanisms at a time was calculated. Pichia guilermondii competed with Botrytis cinerea for glucose, sucrose, adenine, histidine, and folic acid. Viability of the yeast cells played a crucial role in suppression of Botrytis cinerea and they secreted an inhibitory compound that had an acropetal effect and was not volatile. Bacillus mycoides did not compete for any of the sugars, amino acids, or vitamins examined at a level that would affect Botrytis cinerea development. Viable cells and the compounds secreted by them contributed similarly to Botrytis cinerea suppression. The bacteria secreted volatile and non-volatile inhibitory compounds and activated the defense systems of the host. The nonvolatile compounds had both acropetal and basipetal effects. Mixture of Pichia guilermondii and Bacillus mycoides resulted in additive activity compared with their separate application. The combined activity was due to the summation of biocontrol mechanisms of both agents. This work provides a theoretical explanation for our previous findings of reduced disease control variability with a mixture of Pichia guilermondii and Bacillus mycoides.  相似文献   

3.
ABSTRACT Botrytis cinerea is an economically important pathogen. Epidemiological studies are difficult because of the genetic variability within this species. The objectives of this work were to study the variability and to compare the inhibitory effects of Ca on three isolates of B. cinerea from decayed apple (B) and grape (C and C77:4). Among these isolates, B had the least radial growth but had a sporulation rate 40% higher than that of both C77:4 and C. In situ, isolate C incited the largest decay area in the fruit of two of four apple cultivars examined and had the highest polygalacturonase activity in vitro. Maximum mycelial growth was reached with CaCl(2) at 1 g liter(-1) for isolates B and C77:4 and at 4 g liter(-1) for isolate C. Calcium (CaCl(2)) inhibited polygalacturonase activity at 1 g liter(-1) for C and C77:4 and at 16 g liter(-1) for B. Calcium infiltration reduced decay caused by all three isolates by three to five times. Mycelial DNA analysis showed that 42% of the character loci scored were polymorphic and the greatest similarities were found between B and C77:4. These results support the evidence that the biological and statistical variability in research can be affected by the B. cinerea isolate selected. Despite this variation, Ca treatment of apples reduced decay caused by all three Botrytis cinerea isolates.  相似文献   

4.
Huang R  Li GQ  Zhang J  Yang L  Che HJ  Jiang DH  Huang HC 《Phytopathology》2011,101(7):859-869
A study was conducted to identify volatile organic compounds or volatiles produced by Candida intermedia strain C410 using gas chromatography-mass spectrometry, and to determine efficacy of the volatiles of C. intermedia in suppression of conidial germination and mycelial growth of Botrytis cinerea and control of Botrytis fruit rot of strawberry. Results showed that, among 49 volatiles (esters, alcohols, alkenes, alkanes, alkynes, organic acids, ketones, and aldehydes) identified from C. intermedia cultures on yeast extract peptone dextrose agar, two compounds, 1,3,5,7-cyclooctatetraene and 3-methyl-1-butanol, were the most abundant. Synthetic chemicals of 1,3,5,7-cyclooctatetraene; 3-methyl-1-butanol; 2-nonanone; pentanoic acid, 4-methyl-, ethyl ester; 3-methyl-1-butanol, acetate; acetic acid, pentyl ester; and hexanoic acid, ethyl ester were highly inhibitory to conidial germination and mycelial growth of B. cinerea. Inhibition of conidial germination and mycelial growth of B. cinerea by volatiles of C. intermedia was also observed. Meanwhile, results showed that incidence and severity of Botrytis fruit rot of strawberry was significantly (P < 0.01) reduced by exposure of the strawberry fruit to the volatiles from C. intermedia cultures or C. intermedia-infested strawberry fruit. These results suggest that the volatiles of C. intermedia C410 are promising biofumigants for control of Botrytis fruit rot of strawberry.  相似文献   

5.
生防菌株YB-81的鉴定及其对番茄灰霉病的防效   总被引:3,自引:0,他引:3  
为明确生防菌株YB-81对番茄灰霉病的防病作用及其分类地位,采用平板对峙及含毒介质法测定了其对番茄灰霉病菌的抑菌作用,并测定了该菌株盆栽防病效果及抑菌谱,通过形态学、生理生化特征以及分子鉴定相结合的方法鉴定了YB-81菌株。结果表明:YB-81菌株对番茄灰霉病菌抑菌作用强,抑菌带和抑制率分别为15 mm和80.5%;盆栽防效较好,发酵产物稀释10倍的预防效果达到77.5%,治疗效果不及预防效果;YB-81菌株具有广谱的抑菌活性;根据形态特征、生理生化特征以及16S rDNA序列分析结果将YB-81菌株鉴定为枯草芽胞杆菌。  相似文献   

6.
本文研究了出芽短梗霉Aureobasidium pullulans菌株Yw1防治储藏期草莓果实灰霉病Botrytiscinerea的效果,并对其防病机制进行了初步探索。结果表明,菌株Ywl可以有效的控制储藏期草莓灰霉病的发生,发病率可由95.1%降至30.5%-55.6%,菌株Ywl产生的挥发性物质可以抑制灰葡萄孢菌丝生长,抑制率达到52.1%。去除菌体的上清液对灰霉菌无明显抑制活性,说明其抗菌作用机制可能是活菌的竞争作用。由此可见,菌株Ywl是1株有应用潜力的生防菌。  相似文献   

7.
Köhl J  Molhoek WM 《Phytopathology》2001,91(5):485-491
ABSTRACT The saprophytic fungus Ulocladium atrum was selected for its ability to competitively exclude Botrytis spp. from aboveground necrotic plant tissues which can play a crucial role in the epidemiology of diseases caused by necrotrophic Botrytis spp. Fungal growth in necrotic aboveground tissues can be hampered by fluctuating water availability. Adaptation to these adverse conditions is a key factor for the successful establishment of an antagonist population in this niche. Conidia of U. atrum germinated at water potentials between -1 and -7 MPa on water agar. Germinated conidia survived one to three interruptions of moist incubation by periods at -10 or -42 MPa. The speed of germination was significantly slower with interruption of the moist period as compared with the control, which had continuously moist incubation. However, the maximum germination percentage was the same for conidia incubated with or without interruption of the moist incubation. In bioassays with necrotic cyclamen leaves at -1, -3, and -7 MPa, U. atrum significantly reduced the sporulation of B. cinerea by more than 80%. The results demonstrate that U. atrum tolerates water stress during competitive substrate colonization with B. cinerea. The antagonist is, therefore, an attractive candidate for field applications on aboveground tissues.  相似文献   

8.
Cook DW 《Phytopathology》2002,92(12):1293-1299
ABSTRACT A mechanism that could contribute to the suppression of Botrytis cinerea during pathogen sporulation was examined in this study. Yeasts capable of binding to B. cinerea were formulated with a cellulose carrier and applied to sporulating colonies of the pathogen. The particles from this yeast/cellulose product attached to B. cinerea conidia in the sporulating colony. Inoculum from treated colonies was harvested and applied to tomato stem tissue to test for subsequent pathogenicity. Disease development from inoculum obtained from cultures that had been treated with Trichosporon pullulans was significantly retarded (P = 0.0001) compared with cellulose-only controls. However, between 5 and 11% of conidia applied were attached to yeast cells. The removal of conidia not attached to yeast resulted in inoculum composed of >90% of conidia attached to yeast, and from this inoculum, disease development was significantly retarded (P < 0.05). When inoculum from treated B. cinerea colonies was applied to nutrient limiting agar and then incubated, the B. cinerea conidia germinated, and yeast cells infested the new hyphal growth. Constraints of the formulation of the yeast used in this study, and the implications of this vectoring approach for the suppression of B. cinerea during pathogen sporulation are discussed.  相似文献   

9.
ABSTRACT The exo-beta-1,3-glucanase (EC 3.2.1.58) activity of Pichia anomala strain K, an antagonistic yeast of Botrytis cinerea on postharvest apples, was studied in a synthetic medium supplemented with laminarin, a cell wall preparation (CWP) of B. cinerea, or glucose. The highest enzyme activity was detected in culture media containing a CWP of B. cinerea as the sole carbon source, whereas the lowest activity was observed in culture media supplemented with glucose. Exoglc1, an exo-beta-1,3-glucanase, was purified to homogeneity from culture filtrates of strain K containing a CWP. The molecular mass of exoglc1 was estimated to be under 15 kDa. Optimum activity of exoglc1 was recorded at 50 degrees C and pH 5.5. The exoglc1 K(m) value was estimated at 22.4 mg/ml. Exoglc1 showed in vitro a stronger inhibitory effect on germ tube growth of B. cinerea than on conidia germination and caused morphological changes such as leakage of cytoplasm and cell swelling. Exo-beta-1,3-glucanase activity was detected on apples treated with strain K and was similar to exoglc1 on the basis of activity on native gel. Moreover, the addition of a CWP to a suspension of P. anomala stimulated both in situ exo-beta-1,3-glucanase activity and protective activity against the pathogen, strengthening the hypothesis that exo-beta-1,3-glucanase activity is one of the mechanisms of action involved in the suppression of B. cinerea by P. anomala strain K.  相似文献   

10.
ABSTRACT Botrytis blight (gray mold), caused by Botrytis cinerea, is one of the most widely distributed diseases of ornamental plants. In geranium plants, gray mold is responsible for important losses in production. The mold Aspergillus giganteus is known to produce and secrete a basic low-molecular-weight protein, the antifungal protein (AFP). Here, the antifungal properties of the Aspergillus AFP against various B. cinerea isolates obtained from naturally infected geranium plants were investigated. AFP strongly inhibited mycelial growth as well as conidial germination of B. cinerea. Microscopic observations of fungal cultures treated with AFP revealed reduced hyphal elongation and swollen hyphal tips. Washout experiments in which B. cinerea was incubated with AFP for different periods of time and then washed away revealed a fungicidal activity of AFP. Application of AFP on geranium plants protected leaves against Botrytis infection. Cecropin A also was active against this pathogen. An additive effect against the fungus was observed when AFP was combined with cecropin A. These results are discussed in relation to the potential of the afp gene to enhance crop protection against B. cinerea diseases.  相似文献   

11.
丁香酚对灰葡萄孢的抑制作用研究   总被引:8,自引:0,他引:8  
丁香酚是从植物中提取的天然化合物。采用菌丝生长速率法测定了其对多种植物病原真菌的抑制作用以及田间分离得到的7株灰葡萄孢Botrytis cinerea对丁香酚的敏感性,同时测定了丁香酚对B.cinerea 03 孢子和菌核的抑制活性。结果显示,丁香酚对多种植物病原真菌均有不同程度的抑制作用;灰葡萄孢不同菌株对丁香酚的敏感性不同,EC50值在29.97 ~83.62 μg/mL之间;丁香酚可抑制灰葡萄孢产孢,但对孢子萌发无影响,可抑制其菌核的产生和萌发。荧光染色结果表明丁香酚能破坏灰葡萄孢菌丝细胞膜。利用原子吸收光谱法和紫外分光光度法分别测定丁香酚处理前后菌丝培养液中K+浓度和OD260值变化,结果显示处理后K+浓度和OD260值均升高。综上所述,细胞膜可能是丁香酚对灰葡萄孢菌丝的作用位点。  相似文献   

12.
A radioimmunosorbent assay was developed for Botrytis cinerea which can be used to detect as little as 100 ng of Botrytis mycelium (dry weight). Of 22 fungi tested in the assay, all significant reaction was restricted to members of the Sclerotiniaceae. No reaction was obtained with representative isolates of Aspergillus, Alternaria or Peiticillium. Other Botrytis species gave the most reaction relative to B. cinerea. and related genera such as Monilinia and Sclerotinia yielded small reactions. The assay can be used to detect fi. cinerea infection of grape berries when as little as 0.1 % of homogenate from infected fruit is mixed with homogenate from sound fruit to simulate a minor infection. The assay of free run juice from various lots of grapes was highly correlated with visual assessments of infection in the field. Pursuant to various theories concerning bloom time infection, the assay was used to analyse the B. cinerea content of immature berry tips and floral debris; however, no evidence of such colonization was obtained.  相似文献   

13.
利用响应面分析法优化贝莱斯芽孢杆菌TCS001的发酵条件   总被引:1,自引:0,他引:1  
杨可  司文  林海  林方锐  袁静  陈杰 《农药学学报》2019,21(4):444-452
贝莱斯芽孢杆菌Bacillus velezensis TCS001是一种新型生防细菌,为了提高其生防作用,本文开展了培养基发酵条件优化研究。以TCS001发酵滤液对黄瓜灰霉病菌Botrytis cinerea的抑制率为因变量,先从NB、BPY、YT、BP、LB和SOB 6种基础发酵培养基中筛选最佳基础培养基,再利用Plackett-Burman (PB) 试验筛选出影响发酵滤液抑菌率的关键因素;通过最陡爬坡路径法确定主要影响因素的响应中心点,利用Box-Behnken设计和响应面分析法获得最优发酵条件;通过活体植株喷雾法测定发酵液对黄瓜灰霉病菌的抑制活性,进一步明确其优化效果。最终获得最佳基础培养基为NB培养基,发酵条件为:蛋白胨10.0 g,葡萄糖12.5 g,牛肉浸膏4.0 g,酵母粉1.0 g,蒸馏水1 000 mL,装液量 (体积分数) 40%,种子培养时间16 h,接种量 (体积分数) 3%,转速164 r/min,温度25 ℃,pH 7.0,发酵培养时间36 h。离体抑菌活性试验验证发现,优化培养的发酵滤液抑菌活性最强,抑制率达90.9%;活体盆栽抑菌试验表明,优化培养的发酵液对黄瓜灰霉病的病斑抑制率为74.7%,比优化前提高了36.9%。该结果为贝莱斯芽孢杆菌有效的活性产物分离提取及结构鉴定等后续研究提供了理论基础。  相似文献   

14.
为了解连续施药对番茄灰葡萄孢对咯菌腈敏感性的影响,在温室条件下,从灰霉病发生初期开始,按推荐剂量(有效成分67.5 g/hm2)定期向番茄苗喷施咯菌腈,通过菌丝生长速率法检测灰葡萄孢对咯菌腈的敏感性。结果表明,在番茄1个生长季节中连续施药7次后,病菌对咯菌腈仍表现敏感,其EC50值在0.004 7~0.046 2 μg/mL之间。在含咯菌腈的PDA培养基上对30个灰葡萄孢敏感菌株进行药剂驯化7代后,共产生2个抗药性突变体(Rg-12和Rdz-28),其中Rg-12对咯菌腈的EC50值是其亲本菌株g-12的46倍,Rdz-28的EC50值大于500 μg/mL,2个抗性突变体在菌丝生长速率、产孢量和产菌核能力方面均显著低于其亲本菌株。推测灰葡萄孢可能不易对咯菌腈产生抗性,咯菌腈可作为防治番茄灰霉病的理想候选药剂。  相似文献   

15.
Barnes SE  Shaw MW 《Phytopathology》2003,93(5):573-578
ABSTRACT Botrytis cinerea occurred commonly on cultivated Primula xpolyantha seed. The fungus was mostly on the outside of the seed but sometimes was present within the seed. The fungus frequently caused disease at maturity in plants grown from the seed, demonstrated by growing plants in a filtered airflow, isolated from other possible sources of infection. Young, commercially produced P. xpolyantha plants frequently had symptomless B. cinerea infections spread throughout the plants for up to 3 months, with symptoms appearing only at flowering. Single genetic individuals of B. cinerea, as determined by DNA fingerprinting, often were dispersed widely throughout an apparently healthy plant. Plants could, however, contain more than one isolate.  相似文献   

16.
BACKGROUND: Grey mould caused by the fungus Botrytis cinerea Pers. ex Fr. is one of the major diseases in grapes. The use of fungicides is a simple strategy to protect grapes against B. cinerea disease. However, phenotypes exhibiting resistance to fungicides have been detected in B. cinerea populations. The variation of fungicide‐resistant B. cinerea isolates renders B. cinerea disease control difficult in grapevine fields. RESULTS: The authors have developed a nested polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) method to detect fungicide‐resistant B. cinerea isolates at an early growth stage of grapes in grapevine fields. The nested PCR‐RFLP method was carried out to detect benzimidazole‐, phenylcarbamate‐ and/or dicarboximide‐resistant B. cinerea isolates from grape berries and leaves at Eichorn–Lorenz growth stage 25 to 29. This method successfully detected fungicide‐resistant B. cinerea isolates at an early growth stage of grapes. In addition, only 8 h was required from tissue sampling to phenotyping of fungicide resistance of the isolates. CONCLUSION: It is proposed that the early diagnosis of fungicide‐resistant B. cinerea isolates would contribute to further improvement of integrated pest management against B. cinerea in grapevine fields, and that the nested PCR‐RFLP method is a high‐speed, sensitive and reliable tool for this purpose. Copyright © 2008 Society of Chemical Industry  相似文献   

17.
Bacterial antagonists against Botrytis cinerea were isolated from different Brassica spp. and identified. All isolates showing in vitro antagonism at 4°C were shown to be either fluorescent pseudomonads or Serratia spp. In vitro antagonism against B. cinerea and Alternaria brassicicola was found to depend on the temperature and concentration of nutrients in the medium.
Bacterial strains which showed in vitro antagonism were tested for in vivo antagonism at 4°C against B. cinerea and A. brassicicola using a leaf disc bioassay. Pseudomonas fluorescens isolates CL42, CL66, CL82 and Serratia plymuthica strain CL43 showed inhibition of Botrytis growth on leaf discs; P. fluorescens isolate CL74 and all Serratia liquefaciens isolates exhibited intermediate control. All other fluorescent pseudomonad isolates showed poor control or caused rotting of the cabbage tissue.  相似文献   

18.
Serratia marcescens strain B2 is an effective biocontrol agent against gray mold of cyclamen, caused by Botrytis cinerea Persoon. Strain B2 has strong antifungal activity against B. cinerea in vitro. The culture filtrate was found to contain different types of chitinolytic enzyme activity, including endochitinase and chitobiase activity. Four chitinolytic enzymes were detected among the extracellular proteins of strain B2. Two major enzymes, a 58-kDa endochitinase and a 98-kDa chitobiase, were purified by chromatography and electrofocusing, respectively. Both enzymes inhibited spore germination of B. cinerea. And a red pigment, prodigiosin, extracted and purified from the bacterial cells, also inhibited spore germination. When prodigiosin and the chitinolytic enzymes were applied in concert, a synergistic inhibitory effect was observed. S. marcescens strain B2 has multiple modes of action against the pathogen. Received 14 February 2001/ Accepted in revised form 31 May 2001  相似文献   

19.
为了探明生防酵母菌菌株C410产生的挥发性物质对灰霉菌的抑制作用机理,本文以挥发性物质的主要成分之一环辛四烯为研究对象,测定其对灰霉菌的糖、蛋白、DNA、RNA、细胞的形态及细胞膜通透性的影响。结果表明,在16.5μL/L环辛四烯的作用下,灰霉菌生长速率显著降低,总糖含量基本不变;还原糖含量显著降低;蛋白含量变化不显著;RNA的完整性显著降低。在49.5μL/L环辛四烯的作用下,灰霉菌的生长几乎完全停止,但细胞通透性不受影响,不导致细胞死亡。环辛四烯孵育下灰霉菌DNA分子没有被打断。由此推测还原糖和RNA代谢过程是环辛四烯作用于灰霉菌的重要靶标,抑制其生长及侵染。  相似文献   

20.
Buck JW 《Phytopathology》2004,94(2):196-202
ABSTRACT Control of Botrytis cinerea on geranium seedlings was evaluated in treatments with phylloplane yeasts in combination with 10 fungicides used to manage Botrytis blight of ornamental plants. Rhodotorula glutinis PM4 significantly reduced the development of lesions caused by B. cinerea on geranium cotyledons; however, yeast biocontrol efficacy was highly variable between trials. Treatment with the yeast in combination with azoxystrobin or trifloxystrobin at one tenth the labeled rate (7.5 mug a.i. ml(-1)) or the full labeled rate (7.5 mug a.i. ml(-1)) reduced lesion development, compared to treatment with the yeast or the fungicide alone. Vinclozolin at half the labeled rate or the full labeled rate (250 or 500 mug a.i. ml(-1)), in combination with R. glutinis PM4, significantly reduced the development of lesions caused by an isolate of B. cinerea resistant to vinclozolin. Copper hydroxide and iprodione at one-tenth the labeled rates, with or without yeast, were highly effective in limiting lesion development. Mancozeb did not increase the biocontrol efficacy of the yeast, and thiophanate-methyl negatively affected the yeast efficacy. Improved disease control was observed in treatments with vinclozolin at the labeled rate and R. glutinis PM4 at cell densities of 5 x 10(5) and 1 x 10(6) cells ml(-1), but not 1 x 10(5) cells ml(-1), on seedlings co-inoculated with B. cinerea in a suspension containing 1 x 10(5) conidia ml(-1). Disease control improved in treatments with combinations of vinclozolin and eight other isolates of R. glutinis, two isolates of R. graminis, and two isolates of R. mucilaginosa. Biocontrol was not observed in treatments with two isolates of R. minuta. The combination of yeast and vinclozolin significantly reduced the germination of conidia of B. cinerea and the growth of R. glutinis PM4 in vitro. All combinations of R. glutinis PM4 with azoxystrobin, trifloxystrobin, or vinclozolin provided highly effective and consistent disease control not observed in treatments with the fungicides alone or the yeast alone.  相似文献   

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