Fungicide tolerance of Trichoderma asperelloides and T. harzianum strains (original) (raw)
Related papers
Fungicide tolerance of <i>Trichoderma asperelloides</i> and <i>T. harzianum strains</i>
Agricultural Sciences, 2011
and three of T. asperelloides to increasing concentrations of chemical fungicides. This isolation of Trichoderma was exposed to three fungicides: Captan, Thiabendazol and the mixture Captan-Carboxin. Some selected lines of these strains reached tolerance to Captan and partial tolerance to the mixture Captan-Carboxin. The biological and genetic changes in these tolerant lines were monitored by determining the relative growth rate of the fungus, inhibition of Fusarium and by analyzing the genomic changes through UP-PCR. The results show that the tolerance to fungicides can be developed without affecting the parameters of biological activity in these lines of Trichoderma (growth and parasitism against Fusarium). Chemical tolerance to the fungicide was verified by means of changes at the DNA level (UP-PCR), mainly in the lines tolerant to Captan. This suggests that Trichoderma survives in environments with remnants of fungicide molecules.
Screening of Trichoderma species for tolerance to fungicides
Pakistan Journal of Botany, 2007
Fungicides viz., Benomyl, Topsin-M, Carbendazim and Cuprocaffro were used at different concentrations i.e., 0, 1, 10, 100, 1000 and 10,000 ppm a.i. to evaluate Trichoderma species viz. T. harzianum, T. pseudokoningii, T. longibrachiatum, T. viride for tolerance to fungicides. Topsin-M and Carbendazim were the most effective fungicides that inhibit the growth of Trichoderma species even at low concentration. Topsin-M completely suppressed the growth of T. harzianum at 10ppm.
Sensitivity of wild-type and mutant Trichoderma harzianum strains tofungicides
Ciencia e investigación agraria, 2012
Sensitivity of wild-type and mutant Trichoderma harzianum strains to fungicides. Cien. Inv. Agr. 39(3): 569-576. The germination of conidia in wild-type (Th11, Th12 and Th650) and mutant (Th11A80.1, Th12A10.1 and Th650-NG7) strains of Trichoderma harzianum that were exposed to different commercial fungicides was studied. All wild-type and mutant Trichoderma strains were germinated in the presence of 1,700 mg L-1 of pencycuron. The wildtype strains Th12 and Th650 and the corresponding mutant strains Th12A10.1 and Th650-NG7 were sensitive to all concentrations of iprodione and metalaxil + mancozeb. The EC 50 (Median Effective Concentration) values for the different fungicides were between 10-1 and 10-4 less than the concentrations recommended for field applications; one exception was Phyto-fos on Th650-NG7, where this ratio was 0.72. These results establish whether some of these fungicides can be used in combination with the biocontrol agents evaluated.
Sensitivity of Trichoderma isolates and selected resistant mutants to DMI fungicides
In vitro sensitivity assays of nine isolates belonging to five Trichoderma species, to ten demethylation inhibitor fungicides, showed highly significant differences among both isolates and fungicides. Isolates of T. koningii were the most tolerant to fungicides. Flutriafol, fenarimol and myclobutanil were the least effective in inhibiting growth of Trichoderma isolates. UV mutants resistant to prochloraz or bromuconazole from a wild-type isolate of T. harzianum were obtained. Cross-resistance between prochloraz and bromuconazole was evident in four of the five representative mutants tested. Some mutants showed reduced growth and sporulation. Overall results suggest a good potential for integration of Trichodermu isolates and DMI-fungicides in integrated plant protection schemes.
Compatibility Test of Four Trichoderma spp. Isolates on Several Synthetic Pesticides
AGRIVITA Journal of Agricultural Science
Trichoderma spp. are soil-borne fungus to control biologically of plant pathogens especially resulated by soil-borne pathogens given much attention and play an important role in integrated diseases management (IDM). Genus Trichoderma is the most characteristic beneficial isolated soil fungi because of its competence to guard plants and maintain pathogen community under various soil circumstances. This antagonist has been either everywhere studied or marketable as biopesticides, biofertilizers, and soil amendments (Harman, 2006; Howell, 2003). Trichoderma spp. also provides abundant biologically active suspension, including enzymes to degrade pathogen cell wall and more secondary metabolites (Vinale et al., 2008). Trichoderma spp. have been isolated and screened from several rhizospheres, that was ginger (Soesanto et al., 2005), shallot (Santoso, Soesanto, & Haryanto, 2007), banana (Haryono, Prihatiningsih, Wardhana, & Soesanto, 2009), and pineapple (L. Soesanto collection) rhizospheres. These isolates have been tested to suppress some soil-borne plant pathogens. Trichoderma spp. was used to manage Fusarium oxysporum
Compatibility of Trichoderma harzianum with different fungicides under In vitro
International Journal of Chemical Studies
This study was undertaken to evaluate the compatibility of commonly used agrochemicals at recommended dosages with Trichoderma harzianum at 100, 250, 500, 750 and 1000 ppm concentrations by using poisoned food technique. All the fungicides found to be more compatible and safer to the Trichoderma harzianum (Th-8 isolate) isolate at all the concentration and these fungicides did not adversely affect the growth of test antagonist except Thiram. Metalaxyl was found to be least effective and best compatible with Trichoderma harzianum (Th-8 isolate), since the percent inhibition of Trichoderma (Th-8 isolate) was only 6.68 percent at 1000 ppm concentration. Present finding suggest that compatible fungicides can be used with Trichoderma harzianum in an integrated disease management practices for the control of soil born pathogen.
The use of novel isolates of Trichoderma with efficient antagonistic capacity against Fusarium oxysporum f. sp. lycopersici (FOL) is a promising alternative strategy to pesticides for tomato wilt management. We evaluated the antagonistic activity of 30 isolates of T. asperellum against 4 different isolates of FOL. The production of extracellular cell wall degrading enzymes of the antagonistic isolates was also measured. The random amplified polymorphic DNA (RAPD) method was applied to assess the genetic variability among the T. asperellum isolates. All of the T. asperellum isolates significantly reduced the mycelial growth of FOL isolates but the amount of growth reduction varied significantly as well. There was a correlation between the antagonistic capacity of T. asperellum isolates towards FOL and their lytic enzyme production. Isolates showing high levels of chitinase and β-1,3-glucanase activities strongly inhibited the growth of FOL isolates. RAPD analysis showed a high level of genetic variation among T. asperellum isolates. The UPGMA dendrogram revealed that T. asperellum isolates could not be grouped by their antagonistic behavior or lytic enzymes production. Six isolates of T. asperellum were highly antagonistic towards FOL and potentially could be used in commercial agriculture to control tomato wilt. Our results are consistent with the conclusion that understanding the genetic variation within Trichoderma isolates and their biochemical capabilities are required for the selection of effective indigenous fungal strains for the use as biocontrol agents.
Journal of the Institute of Agriculture and Animal Science
The threats of devastating soil-borne disease, limited availability of its management strategies, development of fungicide-resistant strains, outbreaks of new diseases, and growing concerns regarding nature and the environment have compelled us to use integrated disease management (IDM) strategies with appropriate biocontrol agents. Trichoderma, free-living fungi, are successful antagonists with promising biocontrol potentials and can be used with chemicals and botanicals in the IDM approach to control various plant pathogenic fungi. So, the present experiment was conducted to evaluate the compatibility of Trichoderma harzianum with chemical fungicides and botanicals in in-vitro using a poisoned food technique. The experiment was conducted in a completely randomized design with three replications for each treatment at the central laboratory of the Institute of Agriculture and Animal Science, Lamjung, Nepal, and data were taken at different time intervals and analyzed. For fungicides...
Archives of Phytopathology and Plant Protection, 2011
In this study, the in vitro potential of 42 Trichoderma spp. were evaluated against four isolates of soil borne phytopathogenic fungi viz., Rhizoctonia solani, Macrophomina sp., Sclerotium rolfsii and Pythium aphanidermatum in dual culture techniques and through production of volatile and non-volatile inhibitors. In vitro screening results showed that the proportion of isolates with antagonistic activities was highest for the S. rolfsii followed by R. solani, Macrophomina sp. and P. aphanidermatum, respectively. The isolates TNT1, TNP2 and TWP1 showed consistent results in volatile and non-volatile activity in vitro against any of the two pathogens tested. Based on genomic finger prints, potential isolates showed no particular correlation between the origin of the isolates and the Random Amplified Polymorphic DNA (RAPD) groups could not be established. However, the polymorphism shown by the isolates did not correlate to their level of antagonism. Whereas, in physiology studies using BIOLOG (microbial identification system), three groups were formed, one group consists with 14 different Trichoderma species and two groups with two isolates each comprised of only T. koningii and T. viride.
Compatibility of Trichoderma asperellum with fungicides
2020
Fungicides applied for the management of plant diseases have a toxic effect on the biological control agents. For effective disease management, the activity of biological control agents should not be hampered by the application of fungicides. To find the compatibility of bioagents with the fungicides, we have evaluated the different fungicides against Trichoderma asperellum in vitro. Among contact fungicides, Trichoderma was compatible with copper hydroxide, copper oxychloride and mancozeb, and least compatible with captan. Whereas among systemic fungicides, metalaxyl was compatible at all the concentrations whereas tebuconazole, propiconazole and carbendazim were incompatible. Among combination fungicides, metalaxyl-M + mancozeb was found to be highly compatible whereas other combination fungicides tested were incompatible with Trichoderma.