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1.
Control of Grapevine Grey Mould with Trichoderma harzianum T39   总被引:1,自引:0,他引:1  
The efficacy of a formulation of Trichoderma harzianum T39 for control of grey mould (Botrytis cinerea) on grapevine was examined in 133 experiments conducted under diverse commercial conditions. The experiments were carried out between 1988 and 1994 in 19 countries and on 34 varieties. The average disease incidence in the untreated plots of all experiments was 42 2.3% (mean standard error). In general, the reduction of disease achieved by T. harzianum application was lower than that obtained by chemical fungicides: 36.3 2.7% disease reduction in biocontrol treatments and 52.3 2.6% in the exclusively chemical treatments. Control efficacy declined when the interval between application and assessment dates increased to 5 weeks. The experiments also included treatments in which T. harzianum was integrated with chemical fungicides, the two being applied alternately, and a reduced chemical treatment in which only chemicals were applied, and only at the times when chemicals were applied in the integrated treatment. The mean control efficacy in these treatments was 55.8 3.2% and 44.2 4.9% respectively. The roles of the integration of biological and chemical compounds in reducing pesticide residues in fruit at harvest and lowering the pressure towards development of fungicide-resistance populations of B. cinerea are discussed.  相似文献   

2.
Isolate T39 of Trichoderma harzianum (TRICHODEX) is a commercial biocontrol agent. It controls Botrytis cinerea (grey mould) in greenhouse crops and in vineyards, Sclerotinia sclerotiorum (white mould) in various greenhouse and field crops, Cladosporium fulvum (leaf mould) in tomato, and the powdery mildews Sphaerotheca fusca in cucurbits and Leveillula taurica in pepper. T. harzianum T39 was applied in vineyards and greenhouses as part of grey mould management programmes in alternation with chemical fungicides. In the present study, the effect of T39 on diseases of greenhouse crops was demonstrated. The biocontrol agent was applied in formulations containing two concentrations of the active ingredient, or in the presence of oil in cucumber and tomato greenhouses. Suppression of B. cinerea , C. fulvum and S. sclerotiorum was similar when T39 was applied at final active ingredient rates of 0.2 or 0.4 g l -1 , except for one sampling date in one experiment. The addition of JMS Stylet-Oil did not contribute to the control of the above mentioned diseases achieved by T39.  相似文献   

3.
Chronological events associated with the degradation of Botrytis cinerea by a strain of Trichoderma harzianum selected for superior biocontrol ability were studied using ultrastructure and cytochemical investigations in an attempt to define the relative roles of antibiosis and parasitism in the antagonistic process. The first ultrastructural changes were observed 12 h before contact between the organisms, and were characterized by punctuated invaginations of the Botrytis plasmalemma. These reactions were followed by a gradual retraction of the plasmalemma, disorganization of the cytoplasm, loss of turgor pressure and cell death within 48 h of contact between hyphae of the interacting fungi. The first evidence of penetration of B. cinerea by T. harzianum was recorded 72 h after contact. This penetration was apparently mediated by either mechanical pressure or localized wall digestion at points of entry, as there was no clear evidence of chitinolytic degradation of the B. cinerea cell wall, as determined by cytochemical labelling of chitin with a lectin-gold conjugate. However, after 10 days there was clear indication of chitin degradation, based on the random and reduced presence of gold particles over the cell wall of B. cinerea. These results suggest that the strain of T. harzianum antagonized first and foremost by antibiosis, leading to cell death, followed by degradation of the cell by means of chitinolytic enzymes. The production of antibiotics may, therefore, be more important than that of chitinolytic enzymes in conferring superior biocontrol properties to T. harzianum.  相似文献   

4.
Two biocontrol preparations were tested for their ability to control Sphaerotheca fusca and Botrytis cinerea on greenhouse cucumber. Trichoderma harzianum T39 (TRICHODEX) spray reduced powdery mildew severity by up to 97% but its efficacy declined to 18–55% control as the epidemic progressed. Unlike on young leaves, on older leaves the control of powdery mildew by T. harzianum T39 was poor. Ampelomyces quisqualis (AQ10) was very effective against powdery mildew, achieving up to 98% of control. Its effectiveness declined with the progress of the epidemic but unlike the other biocontrol agent it retained significant control capability on older leaves. Two aliphatic petroleum distillate oil products improved the efficacy of both biocontrol agents. The co-application of T. harzianum T39 and A. quisqualis AQ10 was tested on cucumber plants infected with powdery mildew followed by fruit gray mold infection. It resulted in no improvement of the control of powdery mildew, and in an improvement of gray mold control, the latter probably because of the use of additive oil (ADDQ) along with the second biocontrol preparation. There was no significant interference between the biocontrol agents in the co-application treatment as compared with the application of each agent alone; the level of population of T. harzianum T39 remained similar and the parasitism of S. fusca by A. quisqualis was not nullified. The application of T. harzianum T39 to soil instead of spraying it resulted in 75–90% lower powdery mildew coverage on the leaves. It was concluded that the mode of action of T. harzianum T39 in powdery mildew control is induced resistance, not mycoparasitism or antibiotic action.  相似文献   

5.
A screening programme is described for the assessment of the potential of biocontrol agents to control grey mould of strawberries caused by Botrytis cinerea. Bacteria were isolated from strawberry fruits, leaves and flowers from a commercial field site and screened for antagonism towards B. cinerea using two in vitro and one in vivo screening techniques. From 559 microorganisms isolated, 108 inhibited pathogen growth on agar plates and 27 of these prevented spore germination on Cellophane membranes. The ability of these 27 isolates to inhibit infection of young strawberry leaves by B. cinerea on whole plants under glass was then tested. Seven isolates reduced grey mould development and were subsequently assessed in a field trial. Two isolates, one of Bacillus pumilus and one of Pseudomonas fluorescens, were as effective or more effective than standard dichlofluanid sprays and may therefore be of potential value as antagonists of B. cinerea.  相似文献   

6.
The effect of six isolates of Trichoderma harzianum and one isolate of T. koningii on the incidence and severity of tan spot (Pyrenophora tritici-repentis) and leaf blotch of wheat (Mycosphaerella graminicola) was evaluated under field conditions. Significant differences between wheat cultivars, inoculum types and growth stages were found. Three of the isolates tested (T2 for M. graminicola, T7 for P. tritici-repentis and T5 for both of them) showed the best performance in controlling leaf blotch and tan spot when coated onto seed or sprayed onto wheat leaves at different growth stages, with significant severity reduction up to 56%. At tillering, six of the isolates reduced the severity of P. tritici-repentis and M. graminicola compared to the control by up to 39% and 12-53%, respectively. In some experiments, the biocontrol preparation (T2 and T5) gave a level of disease control similar to that obtained with Tebuconazole (70 and 48%, respectively). The effect of Trichoderma against P. tritici-repentis was also observed at the heading stage, when six of the treatments reduced disease severity by 16-35%. This is the first report on the efficacy of Trichoderma spp. against wheat necrotrophic pathogens under field conditions in Argentina.  相似文献   

7.
Eight strains of Trichoderma species (T. strigosum, T. erinaceus, T. pubescens, T. stromaticum, and T. spirale as well as T. cf. strigosum, T. cf. pubescens) were selected because of their antagonistic potential against Eutypa dieback and Esca which are fungal diseases of grapevine trunks. These isolates were screened for the production of a group of polypeptide antibiotics named peptaibiotics, including its subgroups peptaibols and lipopeptaibols. Fully-grown fungal cultures on potato-dextrose agar were extracted with CH(2)Cl(2)/MeOH, and these extracts were subjected to SPE using C(18) cartridges. The methanolic eluates were analyzed by on-line LC/ESI-MS(n) coupling--a method which is referred to as 'peptaibiomics'. New seven-, ten-, and eleven-residue lipopeptaibols, with N-terminal alkanoyl, and C-terminal leucinol or isoleucinol residues were found and named lipostrigocins and lipopubescins. Furthermore, new 18-residue peptaibols named trichostromaticins and 19-residue peptaibols named trichostrigocins were discovered. One peptaibiotic carrying a free C-terminal valine (or isovaline) named trichocompactin XII was also sequenced. These results corroborate the hypothesis that peptaibiotics might contribute to the plant-protective action of their fungal producers. The data also point out that comparison of peptaibiotic sequences is of limited relevance in order to establish chemotaxonomic relationships among species of the genus Trichoderma.  相似文献   

8.
Pathogenicity test of all fungi (14 different isolates) isolated from both infected tomato fruits and the surface wash of other healthy fruits had different pathogenicity rates. The genus Rhizopus sp. was the most pathogenic one followed by Fusarium sp. Trichoderma harzianum isolates (T3 and T4) had a different pattern of antagonism against the tested pathogens. In dual plate test of the antagonistic action of T3 and T24 against the postharvest pathogens, clear zone size ranged between 1 and 4 and 3 and 6 mm by T3 and T24, respectively. The antagonists (T3 and T24) didn't show inhibition zone against Rhizopus sp., but they could overgrow it by 100% after 9 days of incubation. Mostly, all the other postharvest isolates showed high degree of overgrowth by T3 than T24. The two antagonists failed to overgrow Aspergillus species except for A. niger (3) which was overgrown by T3. Volatile and non-volatile metabolite tests indicated that mycelial growth of Penicillium stekii was significantly inhibited by T3 and T24 more than the other tested pathogens. The inhibition of A. niger (1) was 12% by non-volatile metabolites of T24 produced after 1 day incubation, and reached to 97% inhibition by the metabolites of 3 days. Interestingly, inhibition of Aspergillus sp. by volatile compounds of T3 and T24 was 2% and 20%, respectively, whereas the inhibition of the same pathogen by non-volatile compounds reached 75% and 87%, respectively. The results of slice assay clearly indicate that T. harzianum (T3 and T24) could provide a complete protection to tomato slices from the infection of the tested pathogens. After 3 days of incubation, Trichoderma suppressed the linear growth of these pathogens on tomato slices and the percentage of suppression was significant and ranged between 80 and 100%, except with Rhizopus sp. the suppression reached 33% only.  相似文献   

9.
Abstract

The possible biological control of damping-off fungi, Fusarium oxysporum and Pythium ultimum by Pythium oligandrum or Trichoderma harzianum was in vitro investigated. Results of comparing the antagonistic activity of P. oligandrum and T. harzianum in dual plates against the tested phytopathogens indicated different degrees of antagonism. After 12 days of incubation colony of the phytopathogenic fungus was completely overgrown by the antagonist, except for the interaction between T. harzianum and F. oxysporum which showed no overgrowth or any hyphal penetration by the antagonist. However, growth and proliferation of F. oxysporum colony was repressed. T. harzianum and P. oligandrum produced chitinase and β-1,3-glucanase when they were grown on liquid culture medium supplemented with chitin or fungal dried mycelium as a sole carbon source, and enzyme production was higher by T. harzianum comparing with P. oligandrum under the same condition. Fungal dried mycelium of F. oxysporum was the most selective carbon source for enzyme production, on the other hand, chitinase production was significant locked when P. ultimum dried mycelium was used as a carbon source. Production of volatile compounds by P. oligandrum or T. harzianum against F. oxysporum and P. ultimum was examined using the inverted plates method. F. oxysporum was inhibited by the antagonist volatile compounds and it is inhibited 100% by increasing the amount of inoculum size. Production of potential biocontrol agents provided with economically features and working under field conditions are recommended.  相似文献   

10.
Menendez AB  Godeas A 《Mycopathologia》1998,142(3):153-160
Two experiments of biological control of Sclerotinia sclerotiorum, one in the greenhouse and the other in the field, were carried out with soybean and Trichoderma harzianum as host and antagonist, respectively. Significant control of disease was achieved in both experiments, but there were no significant differences in plant growths. In the greenhouse, the application of T. harzianum as alginate capsules, increased the survival of soybean plants more than 100% with respect to the disease treatment. In the field, T. harzianum treated plants survived 40% more than those from the disease treatment, showing a similar survival level to control plants. Besides, a significant reduction (62.5%) in the number of germinated sclerotia was observed in the Trichoderma treated plot. Chitinase and 1,3-β- glucanase activities were detected when T. harzianum was grown in a medium containing Sclerotinia sclerotiorum cell walls as sole carbon source. In addition, electrophoretic profiles of proteins induced in T. harzianum showed quantitative differences between major bands obtained in the media induced by S. sclerotiorum cell walls and that containing glucose as a sole carbon source. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

11.

The biopreparation Supresivit based on spores from the fungus Trichoderma harzianum was applied as a dressing mixed with mineral fertilizers: NPK, LAV (ammonium nitrate with limestone) and DASA (ammonium nitrate and ammonium sulphate). Our experimental plots with spring barley, winter wheat, winter oil rape, maize and potatoes were fertilized with the mixtures of the biopreparation (1 g, 0.5 g and 0.1 g per 1 kg of fertilizer). There were two check variants, the first variant without any fertilization and without biopreparation, the second with fertilizer and without biopreparation. We observed the infestation of plants with pathogenic fungi and yield parameters. In our experiments it was indicated that Trichoderma harzianum suppresses pathogenic fungi at the concentration 0,5 g of Supresivit per 1 kg of the fertilizer and higher ones. The plants from treated plots had lower infestation - decreasing about 5-15% superficial infestation: tan spot of barley - yellow leaf spot on cereals and leaf blotch of barley, winter wheat - leaf spot of wheat, tan spot of wheat, take-all etc., winter oil-seed rape - black leg and collar rot, potatoes - blight fungus etc. Simultaneously the effect on higher yields was observed.  相似文献   

12.
Antagonistic potential of Trichoderma longibrachiatum and T. hamatum against the pathogen Fusarium verticillioides was examined in the laboratory. This was done by pairing each Trichoderma species with the pathogen on 9 cm Petri plates of acidified potato dextrose agar (APDA). Three pairing methods were employed and gradings were assigned to different radial growth suppression of F. verticillioides by each Trichoderma species. Analysis was done using the GLM procedure of the SAS package. Both Trichoderma species significantly inhibited radial growth of F. verticillioides (P = 0.01, R 2 = 0.99) irrespective of pairing method. ‘Inoculating antagonist before pathogen’ supported the best growth inhibition of F. verticillioides by both Trichoderma species. Both Trichoderma species differed significantly (P > 0.0029) in inhibiting radial growth of F. verticillioides. Growth inhibition differed significantly within (P > 0.0059) and among (P > 0.0001) pairing methods. T. longibrachiatum was significantly better than T. hamatum in inhibiting radial growth of F. verticillioides, even at P = 0.01. T. hamatum and T. longibrachiatum could thus be said to show promising antagonistic potential against F. verticillioides with the latter showing better prospects.  相似文献   

13.
芸芥(Eruca sativa)是当今我国蔬菜市场中一种颇具开发价值的新特芳香蔬菜。为了研制促进芸芥生长和提高品质的生防木霉菌剂,本研究以芸芥为试材,在大田条件下,采用本实验室分离鉴定的哈茨木霉T8进行浸种和浇根处理,分析木霉菌对一个生长季内连续栽培三茬30 d龄芸芥的生长相关生理指标的影响。结果表明,施用木霉菌能显著提高芸芥的生物量,改善其光合特性,增强其防御酶活性和脯氨酸含量,提高其产量和营养价值。  相似文献   

14.
The evaluation of Eurithia consobrina (Meigen) as a candidate for introduction against bertha armyworm, Mamestra configurata (Walker) (Lepidoptera: Noctuidae), in western Canada included studies of its host range, distribution, synchronization with host, constancy, abundance and life history in Europe. In addition, its diapause induction and its coldhardiness were compared with those of the target host M. configurata and its native tachinid parasitoid, Athrycia cinerea (Coq.). E. consobrina was found to fit criteria for a successful biocontrol agent reasonably well. It also had the potential to fill a largely unoccupied niche in the parasitoid complex of M. configurata. E. consobrina has a facultative diapause of the long-day type, similar to A. cinerea, but is less sensitive to diapause-inducing conditions. E. consobrina is at least as coldhardy as A. cinerea and more coldhardy than M. configurata. Laboratory exposures to temperatures of 0 C for 140 days apparently selected for greater coldhardiness, and later generations survived exposures of 140 days at -15 C without significant mortality. Adult E. consobrina were released at three locations in Manitoba in 1986 and 1987, but establishment has not been confirmed.  相似文献   

15.
Genes from the biocontrol fungus Trichoderma atroviride encoding the antifungal proteins endochitinase or exochitinase (N-acetyl--D-hexosaminidase) were inserted into Marshall McIntosh apple singly and in combination. The genes were driven by a modified CaMV35S promoter. The resulting plants were screened for resistance to Venturia inaequalis, the causal agent of apple scab, and for effects of enzyme expression on growth. Disease resistance was correlated with the level of expression of either enzyme when expressed alone but exochitinase was less effective than endochitinase. The level of expression of endochitinase was negatively correlated with plant growth while exochitinase had no consistent effect on this character. Plants expressing both enzymes simultaneously were more resistant than plants expressing either single enzyme at the same level; analyses indicated that the two enzymes acted synergistically to reduce disease. Selected lines, especially one expressing low levels of endochitinase activity and moderate levels of exochitinase activity, were highly resistant in growth chamber trials and had negligible reduction in vigor relative to control plants. We believe that this is the first report of resistance in plants induced by expression of an N-acetylhexosaminidase and is the first report of in planta synergy between an exochitinase and an endochitinase.  相似文献   

16.
The ascomycete Hypocrea jecorina, an industrial (hemi)cellulase producer, can efficiently degrade plant polysaccharides. At present, the biology underlying cellulase hyperproduction of T. reesei, and the conditions for the enzyme induction, are not completely understood. In the current study, three different strains of T. reesei, including QM6a (wild-type), and mutants QM9414 and RUT-C30, were grown on 7 soluble and 7 insoluble carbon sources, with the later group including 4 pure polysaccharides and 3 lignocelluloses. Time course experiments showed that maximum cellulase activity of QM6a and QM9414 strains, for the majority of tested carbon sources, occurred at 120 hrs, while RUT-C30 had the greatest cellulase activity around 72 hrs. Maximum cellulase production was observed to be 0.035, 0.42 and 0.33 µmol glucose equivalents using microcrystalline celluloses for QM6a, QM9414, and RUTC-30, respectively. Increased cellulase production was positively correlated in QM9414 and negatively correlated in RUT-C30 with ability to grow on microcrystalline cellulose.  相似文献   

17.
对基因工程菌株里氏木霉 (Trichodermareesei) 30 6生物合成组织型纤溶酶原激活剂 (t PA)的代谢调节机制进行了研究。在基础发酵条件下 ,L 山梨糖、D 果糖、可溶性纤维素、CMC、麦芽糖、乳糖和棉子糖等单糖及多糖对t PA生物合成都有诱导作用 ,其中L 山梨糖的诱导效果最好 ,加量以 1 .0 %为宜。葡萄糖及其中间代谢产物对t PA的生物合成产生分解代谢物阻遏作用。纤维二糖在低浓度时可以促进t PA的生物合成而在高浓度时对t PA生物合成起反馈阻遏作用  相似文献   

18.
Strains of Pseudomonas fluorescens were investigated for biocontrol efficacy against tomato spotted wilt virus (TSWV) in tomato both alone and in mixtures. P. fluorescens strains applied to seed, soil and foliage or as a seedling dip significantly reduced TSWV, with a concomitant increase in growth promotion in both the glasshouse and field. Two native strains (CoP-1 and CoT-1) and one foreign strain (CHAO) reduced TSWV. In P. fluorescens-treated tomato plants, increased activity of polyphenol oxidase, β-1,3-glucanase and chitinase was observed, and induction of chitinase was confirmed by western blot analysis. Induction of new protein (18 kDa) detected by SDS-PAGE in P. fluorescens-treated tomato plants was not found in healthy and P. fluorescens-untreated virus inoculated control plants. Indirect ELISA clearly showed a reduction in viral antigen concentration in P. fluorescens-treated tomato plants corresponding to reduced disease ratings. All the P. fluorescens-treated tomato plants also showed enhanced growth and yield compared to control plants. Hence, plant growth promoting rhizobacteria (PGPR) could play a major role in reducing TSWV and increasing yield in tomato plants.  相似文献   

19.
Rice husks (RHs) was used as a substrate for biosynthesis of high-value Silica nanoparticles (SiO2NPs). An isolate of Trichoderma harzianum MF780864 (T. harzianum) was isolated and identified based on the Internal Transcribed Spacers (ITS) sequences; it showed the potentiality to induce SiO2NPs in the process of RHs biotransformation. SiO2NPs were produced extracellularly and their size was of about 89 nm. SiO2NPs characterized by oval, rod and cubical particles by using Transmission Electron Microscope (TEM).The Fourier transform infrared spectroscopy (FTIR) confirmed the presence of various functional groups of biomolecules and capping protein, encapsulating SiO2NPs. Water and fish samples were collected from private fish farms in El-Sharkia Governorate, Egypt. Lead (Pb) was detected from water and fish samples at its highest concentration at about 0.088 mg/L. The adsorption capacity of Pb by SiO2NPs was evaluated by testing different concentrations of SiO2NPs viz. 1, 2, and 3 mg/L, wherein 1 mg/L revealed the highest Pb adsorption efficiency. Within laboratory trials, the results indicated that highest Pb adsorption efficiency revealed through the increasing of SiO2NPs concentrations until 120 h. In vivo trial that lasted for 8 weeks, Nile tilapia (Oreochromis niloticus) (29.78 ± 0.36 g body weight) supplemented with 0.088 mg/L Pb was divided into four experimental groups having three replicates (15 fish/replicate; 45 fish/group). The results showed that SiO2NPs supplementation through water revealed significant increase in growth and hematological parameters of O. niloticus. Moreover, enhancement of antioxidant capacity (TAC), and immune related gene expression of IL-1β were increased in the presence of SiO2NPs compared with the groups of Pb exposure. Moreover, Pb residue level in fish muscles was noticeably decreased in the SiO2NPs treated groups. Thus, this research opens up other possibilities in the field of using SiO2NPs as a lead adsorbent for water bioremediation.  相似文献   

20.
The efficiency of Trichoderma harzianum (MIAU 145 C) in promoting kidney bean (cv. Goli) growth in different soil texture (sandy loam, loam and clay loam) and organic matter content (0.5 and 2% of leaf litter) was assessed in a factorial experiment in the absence of Meloidogyne javanica. In another factorial experiment, the effect of soil texture, soil organic content and control measure (no control, 10?ml of T. harzianum containing 106 spore ml?1 and 2?mg ai cadusafos kg?1 soil) was determined on nematode-infected kidney bean’s growth, fungus controlling activity and M. javanica reproduction. Except for the shoot length, the fungus improved plant growth. Clay loam was not a proper soil type for the cultivation of kidney bean plants (even in the soil without nematode), but the plant grew better in sandy loam and loam soil. The presence of leaf litter in the soil enhanced plant growth, increased fungal efficiency and increased nematode reproduction. It seems that T. harzianum can activate the plant defence system in sandy loam soil. T. harzianum was more effective in sandy loam or loam soil containing 2% organic matter (leaf litter) and reduced the reproduction factor of the nematode in the tested soil textures equally to the chemical nematicide treatment.  相似文献   

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