For exploring the influences of application and residue of chemical fungi- cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia gro...For exploring the influences of application and residue of chemical fungi- cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia growth of two bio- control fungi T. harzianum 610 and T. Iongibrachiatum 758 were studied. Carben- dazim, tebuconazole and difenoconazole showed strong toxicities, thiram and car- bexin showed moderate toxicities, and metalaxyl showed Mycelia growth of the two strains was more sensitive to most tested fungicides than those of chlamydospore germination. Chlamydospore germination of 610 was more sensitive to tested fungicides than those of 758, and mycelia growth of 758 was more sensitive to most tested fungi- cides than those of 610. Among the seven fungicides, 98% carbendazim had the strongest effects (ECru values were 1.64 and 0.05μpg/ml), and 70% pentachloroni- trobenzene had the weakest effects (EC50 values were 1.64 and 0,05 μg/ml) for chlamydospore germination and mycelia growth of 610. As for 758, 98% carbendaz- im had the strongest inhibitory effects and 95% metalaxyl had the weakest inhibitory for chlamydospore germination of 756 (EC50 values were 0.62 and 1 108.61 μg/ml respectively), whereas 96.2% tebuconazole showed the strongest inhibitory effects for mycelia growth of 758 (EC= value was 0.32μg/ml), and 95% metalaxyl was the weakest (EC= value was 1 206.29 μg/ml). According to the applied concentration of different fungicides in practice, we concluded that chlamydospore preparations of 610 and 758 could not be combined with carbendazim, tebuconazole, thiram and carboxin for controlling plant diseases, and the pesticide residues to the biocontrol effects should be kept in mind. Chlamydospore preparations of 610 and 758 can be and difenoconazole for controlling plant dis- eases, 758 chlamydospore preparations and germinated chlamydospore of 610 can be combined with metalaxyl for controlling plant diseases, and pesticide residue risk was not serious.展开更多
[Objective] This study was conducted to investigate the effects of Penicillium spp. and Trichoderma spp. on the growth of Pleurotus ostreatus (oyster mushroom) and to screen effective disinfectants to control them a...[Objective] This study was conducted to investigate the effects of Penicillium spp. and Trichoderma spp. on the growth of Pleurotus ostreatus (oyster mushroom) and to screen effective disinfectants to control them and other pathogenic microbes. [Method] Six strains or species of Penicilliurn and Trichoderma were inocu- lated into PDA plates growing with P. ostreatus to observe the growth of their mycelia. And the inhibitory effects of hydrogen peroxide, bromogeramine bromide, 84 disinfectant, lysol, potassium permanganate, and 75% medical alcohol on Trichoderma pleuroticola, Trichoderma viride, Trichoderma harzianum, Penicillium citrinum, Penicillium thomii and Penicillium brevicompactum were detected. [Result] Confrontation test revealed that Penicillium spp. and Trichoderma spp. competed for nutrients with P. ostreatus mycelia, antagonized against the growth of P. ostreatus mycelia, invaded and twined around P. ostreatus mycelia, and also produced toxins poisoning P. ostreatus mycelia. The six disinfectants exhibited different inhibitory effects against different species of Penicillium and Trichoderma. Among them the in- hibitory effects of bromogeramine bromide against the six species of Penicillium and Trichoderma were significantly different. However, the inhibitory effects of 3% hydrogen peroxide, 84 disinfectant, 5% lysol, potassium permanganate and 75% medical alcohol were significantly different among Penicillium spp., but did not among Tri- choderma spp. [Conclusion] Bromogeramine bromide can be used to control the bacteria and fungi in mushroom production for it has significant inhibitory effects on the six species of both Penicillium and Trichoderma.展开更多
Trichoderma spp. is a filamentous soil fungus known as an effective biocontrol agent of a range of important airborne and soilborne pathogens, it has universal distribution and economic importance. This article review...Trichoderma spp. is a filamentous soil fungus known as an effective biocontrol agent of a range of important airborne and soilborne pathogens, it has universal distribution and economic importance. This article reviewed the researches on biocontrol mechanism for plant diseases and application of Trichoderma spp., especially Trichoderma harzianum in recent years展开更多
Different from ribosomal genes, which contain highly conserved sequences that are detected in all organisms, the intergenic spacer of rDNA (IGS) appears to be the most rapidly-evolving spacer region. For this reason w...Different from ribosomal genes, which contain highly conserved sequences that are detected in all organisms, the intergenic spacer of rDNA (IGS) appears to be the most rapidly-evolving spacer region. For this reason we tested this region for phylogenetic studies. This report focuses on the study of IGS sequences of isolates belonging to Trichoderma section (T. viride, T. koningii, T. hamatum, T. erinaceus, T. asperellum) and Pachybasium section (T. harzianum, T. crassum, T. fasciculatum, T. oblongisporum, T. virens). Using the primer pair 28STD and CNS1, the Fast Start Taq DNA Polymerase (Roche), and a three temperature PCR protocol, products ranging from ca 1900 to 2400 bp were obtained from all tested isolates. The PCR product of 16 Trichoderma spp. isolates was cloned into a pGEM-TEeasy Vector (Promega) and sequenced. Based on a BLAST search we can conclude that the PCR product represents the whole IGS region. Multiple alignments of IGS sequences revealed two portions with different homology level. Portion A (ca 1660 bp) is the portion that contains 3’ end of 28S gene and is the more variable, while portion B (ca 830 bp), that contains the 3’ end of IGS region and the 5’ end of 18S gene, is the less variable. Comparing all sequences in region A 705 identical pairs occur out of 1704 total nucleotides (41.4%), while in region B identical pairs were 723 out of 832 total nucleotides (86.9%) . Sequence comparison of the two regions at intraspecific level (where it was possible) showed higher variability in region A (0.17%-6.8%) than in region B (0.0%-1.0%) . At interspecific level, performing all possible comparisons, the variability of region A (19.5%-52.7%) and B (0.8%- 16.9%). were significantly higher. Comparing sequences of species belonging to Trichoderma section variability of the two regions appears reduced if compared with that obtained from comparisons of species belonging to Pachybasium section. On the basis of sequence alignment, phylogenetic trees were obtained either with entire IGS, with region A, and with region B. Results of this analysis revealed that all isolates belonging to Trichoderma section grouped separately from isolates belonging to Pachybasium section. IGS region allowed us to group species according to their taxonomic position. The topology of the tree did not change substantially, varying in genetic distance only. Performing a GenBank search sequences representing the final portion of the IGS region of other fungal species were found, and we carried out a multiple alignment using also our sequences of Trichoderma spp. and Diaporthe helianthi. The phylogeny inferred from sequence alignment matched the generally accepted morphology-based classification and was identical to other molecular schemes at high taxonomic level. Data analysis was useful in establishing a broad-scale phylogeny of Ascomycota and was also useful in sorting them into statistically-supported clades. The tree showed that Trichoderma occurred in a well-supported terminal subclade of a larger clade that also contained other genera belonging to Hypocreales order. Sequence analysis of the Trichoderma spp. IGS region allowed us to design a specific PCR primer that was successfully used to amplify region A. The new reverse primer LCR2, that recognize all Trichoderma isolates, was identified in region B and confirmed for its specificity on the DNA of fungi belonging to other Ascomycota genera. Results obtained showed that IGS region seems to be an interesting and versatile tool for phylogenetic analysis, for resolving some taxonomic problems and for constructing specific primer useful for different purposes.展开更多
The soil is a complex system where processes have direct influence on crop nutrition and plant health. Unfortunately, most of the agricultural soil management practices, compact them producing poor oxygenation, low be...The soil is a complex system where processes have direct influence on crop nutrition and plant health. Unfortunately, most of the agricultural soil management practices, compact them producing poor oxygenation, low benefic microorganism populations and metabolic disorders in plants. Those factors induce abnormal plant development and predisposition to the attack of soil borne plant pathogens as: Sclerotium cepivorum, Sclerotium rolfsi, Sclerotinia sclerotiorum, Rhizoctonia solani, Rosellinia spp. But also, some air borne pathogens as Colletotrichum sp., are more aggressive under those conditions. In Costa Rica some practical trails done by farmers, have shown that the addition of Trichoderma spp. to organic fertilizers like vermicompost, Bocashi, and other composts, has a positive effect on the structure and microbial diversity, that improves nutrient movement in plants and pathogen suppression. Vegetative material of leather fern (Rumohra adiantiformis) infected by Rosellinia spp., planted with bocashi amended with. T. asperellum (T. harzianum), showed more tip root growth and new fern rhizomes. Also the plants produced higher number of fiddleheads and high quality fronds. Non-treated material showed a total loss. In some leaf vegetables as lettuce the use of vermicompost followed by Trichoderma viride application, inhibited S. sclerotiorum development on the crop, in this study sclerotia were infected and plant yields were increased. Compost previously inoculated with Trichoderma, inhibited 100% the Botrytis and R. solani infection, in nurseries, and plant nutrition was improved. The observed results are attributed to the antagonistic effect of Trichoderma on soil and airborne pathogens, production of growth regulators, solubilization of some microelements and better mineral absorption with the development of more roots and elimination of diseased roots. As conclusion, the organic substrates inoculated with Trichoderma spp., besides the organic matter source, they improve the structural characteristics of soil, promote the biochemical processes, increases the level of growth regulator substances and inhibit plant disease as well.展开更多
A series of highly taxonomically diverse Trichoderma strains were investigated using proteomic approaches, to investigate the utility of protein profiles as taxonomic markers and to identify proteins of potential econ...A series of highly taxonomically diverse Trichoderma strains were investigated using proteomic approaches, to investigate the utility of protein profiles as taxonomic markers and to identify proteins of potential economic importance. Initial studies have focused on a comparison of single strains of T. aureoviride, T. saturnisporum, T. polysporum, T. longbrachiatum and T. spirale, along with two strains of T. harzianum. All seven strains were grown in synthetic medium supplemented with 2%(w/v) glycerol, to maximize the diversity of extracellular protein production. Samples of secreted protein were separated by 2D gel electrophoresis and will be characterized by MALDI-TOF peptide fingerprinting.展开更多
The study was conducted to determine the viability of producing organic onion under the fully converted area of Ramon Magsaysay Center for Agricultural Resources and Environment Studies (RMC-ARES), Central Luzon Sta...The study was conducted to determine the viability of producing organic onion under the fully converted area of Ramon Magsaysay Center for Agricultural Resources and Environment Studies (RMC-ARES), Central Luzon State University, Philippines. Specifically, the study aimed to establish the fi'equency of organic fertilizer and Trichoderma spp. application, employing split application, and determine the yield performance of red onion (bulb type). The research was conducted for two consecutive dry seasons (2014 and 2015). Red Creole variety was used with the following treatments: T1--organic fertilizer alone (8 ton/ha) at planting; T2--organic fertilizer (8 ton/ha) applied twice (at basal and 30 d after transplanting (DAT)); T3---organic fertilizer (8 ton/ha) applied twice (at basal and 30 DAT) + Trichoderma spp. at the rate of 526 kg/ha applied at planting; T4----organie fertilizer at 8 ton/ha rate + Trichoderma spp. at the rate of 526 kg/ha, both applied twice (at planting and 30 DAT); T5--organic fertilizer at 8 ton/ha rate applied twice (at planting and 30 DAT) + Trichoderma spp. at the rate of 526 kg/ha applied thrice (at planting, 30 DAT and during bulb formation). Results of the study showed that application of the recommended rate of organic fertilizer twice (at planting and 30 DAT) + three times application of Trichoderma spp. (at planting, 30 DAT and during bulb formation) consistently produced bigger bulb during the first and second trial of the study, compared to other treatments evaluated. Consequently, higher marketable yield was produced with 15.33 ton/ha during the first trial and 14.50 ton/ha on the second trial.展开更多
Trichoderma spp. have been known for their strong abilities to produce extracellular enzymes, especially cellulases and glucanases by T. reesei, and also for their abilities to control plant pathogens. Most notably, a...Trichoderma spp. have been known for their strong abilities to produce extracellular enzymes, especially cellulases and glucanases by T. reesei, and also for their abilities to control plant pathogens. Most notably, a number of lines of evidence indicate that the agriculturally relevant strains are synergistic plant symbionts. As plant symbionts they possess the following characteristics: (a) they infect plant roots but cause the plant to restrict their growth to outer layers of the plant cortex (an exception is the recent discoveries of plant endophytic strains of Trichoderma and Gliocladium ), (b) they produce bioactive plant molecules in the zone of interaction that (c) induce localized systemic resistance to plant diseases and (d) systemic plant resistance to diseases that in some respects is similar to that induced by rhizobacteria, (e) they induce changes in plant proteomes, (f) increase plant growth and yield at least in part by enhancing root growth, and (g) they increase plant nutrient uptake. The increase in plant growth and yields is strongly interactive with plant genotype, at least in maize. There also are very significant increases in the knowledge of events that occur in mycoparasitism that in many respects have features in common with their interactions with plants. They are highly resistant to toxicants and have recently been shown to degrade cyanide and take up, and then degrade, metallocyanides. These discoveries allow new uses for the organisms in managed plant systems, including agriculture. For example, the induced systemic resistance system allows control of fungi, bacteria, Oomycetes and even one virus at sites temporally and spatially distant from the site of application. The abilities of the fungi to resist/degrade toxicants and increase plant growth indicate they will highly useful components in plant-microbe or microbe-only strategies for remediation of soil and water pollution. Finally, there are new uses of their enzyme systems for production of chitin degradation products for use as nutraceuticals or pharmaceuticals.展开更多
Phytophthora species are particularly aggressive plant pathogens and are often associated with the decline of many tree species, including oak and beech. Several fungi and bacteria species are known as potential antag...Phytophthora species are particularly aggressive plant pathogens and are often associated with the decline of many tree species, including oak and beech. Several fungi and bacteria species are known as potential antagonists usable as biological control agents. Phosphonate (H3PO3), commonly branded as phosphite, has also been used in the past years to protect trees against invasive Phytophthora spp.. This study aimed at comparing the effects of selected antagonist microorganisms and phosphonate, when applied by microinjection or leaf treatment. Antagonistic species were first selected for their high inhibitory activity against problematic Phytophthora species, such as Phytophthora cactorum, P. quercina and P. plurivora attacking Quercus robur and Fagus sylvatica in Polish forests. Three endophytic species Trichoderma atroviride (two strains), T. harzianum and Bacillus amyloliquefaciens showed a high control activity, and their efficacy was then assessed in comparison with a phosphonate treatment. Two application methods were experimented in this study: injection of a solution of spores or phosphonate into the sap vessels of beech or a foliar treatment on oak. Phosphonate and two strains of Trichoderma significantly reduced the necrotic area on oak leaves inoculated with P. plurivora and one strain of T. atroviride significantly reduced necrotic areas on beech branches. These results are therefore promising of a novel way to control Phytophthora spp. in forest stands and nurseries.展开更多
Variations in the radial growth rate of 24 isolates belonging to ten species of Trichoderma, three isolates of conifer pathogen Heterobasidion annosum s.s. and four isolates of H. parviporum were evaluated by incubati...Variations in the radial growth rate of 24 isolates belonging to ten species of Trichoderma, three isolates of conifer pathogen Heterobasidion annosum s.s. and four isolates of H. parviporum were evaluated by incubation on a solid malt extract medium at a temperature of 4℃, 15℃ and 21℃. Trichoderma antagonism against Heterobasidion was investigated in dual culture in vitro. The slowest rate of growth was referable to all seven strains of Heterobasidion spp. All Heterobasidion spp. strains were overgrown by 63% of Trichoderma spp. strains after two weeks at 21℃ and by 33% of strains at 15℃. 21% of Trichoderma strains did not grow and only four strains belonging to T. koningii, T. viride and T. viridescens demonstrated the ability to completely overgrow Heterobasidion spp. after two weeks incubation at 4℃. According to the antagonistic efficiency, Trichoderma strains were divided into five groups with an Euclidean distance of 25. The groups contained isolates from different species. It was suggested that selected psychrotrophic fast growing T. viride, T. koningii and T. viridescens strains could be examined in different substrate conditions as suitable antagonist agents for the control of H. annosum and H. parviporum.展开更多
Maize is the main crop for Mexicans;however, it is affected by species of fungi causing ear rot. This research aimed to evaluate the effect of T. asperellum T11, T. harzianum T1 4 y T. longibrachiatum T1 40 on some ag...Maize is the main crop for Mexicans;however, it is affected by species of fungi causing ear rot. This research aimed to evaluate the effect of T. asperellum T11, T. harzianum T1 4 y T. longibrachiatum T1 40 on some agronomic variables of four maize genotypes. The seeds of the genotypes H-515, Zapata 7, and H-507 were treated with a suspension of Trichoderma spp. to 1 × 10<sup>8</sup> spores mL<sup>-1</sup>, using a control (untreated seed), and Benomyl as chemical control. The planting was in Morelos, in a completely random block design with a factorial arrangement. The ear rot was natural. Data were obtained at the end of the crop cycle and processed in SAS 9.4<sup><sup>®</sup></sup>. H-515 genotype had the greatest effect on the treatment of maize seeds with Trichoderma spp. (5.562 kg);T. asperellum T11 was the strain that stood out with a mean yield of 50 ears in an area of 16 m<sup>2</sup> of 4.904 kg, and control of 4.448 kg. Our results are an economic option for farmers to contemplate the use of Trichoderma and obtain its benefits.展开更多
Microbes that are beneficial to plants are used to enhance the crop growth,yield and are alternatives to chemical fertilizers.Trichoderma and Bacillus are the predominant plant growth-promoting fungi and bacteria.The ...Microbes that are beneficial to plants are used to enhance the crop growth,yield and are alternatives to chemical fertilizers.Trichoderma and Bacillus are the predominant plant growth-promoting fungi and bacteria.The objective of this study was select,characterize,and evaluate isolates of Trichoderma spp.and Bacillus spp.native from the northern region of Sinaloa,Mexico,and assess their effect on growth promotion in maize(Zea mays L.).In greenhouse conditions,four Trichoderma isolates and twenty Bacillus isolates,as well as two controls,were tested in a completely randomized design with three replicates.We selected the two best strains of Trichoderma and Bacillus:TB=Trichoderma asperellum,TF=Trichoderma virens,B14=Bacillus cereus sensu lato and B17=Bacillus cereus,which were evaluated in the field in a completely randomized blocks in factorial arrangement design with three replicates applying different rates of nitrogen fertilizer(0,150 kg N/ha,and 300 kg N/ha).Treatments 5(B17=B.cereus)and 11(TF=T.virens)both fertilized with 150 kg N/ha showed similar yields and they did not reveal significant differences from the treatments fertilized with 300 kg N/ha.This indicated that treatment 5(B17=B.cereus with 150 kg N/ha)and treatment 11(TF=T.virens with 150 kg N/ha)were efficient as growth promoters,by not showing significant differences in root volume and dry weight of foliage.The results indicated a reduction of 50% in the rate of nitrogen to fertilizer required for maize(Zea mays L.)crops.These microorganisms Trichoderma and Bacillus could be an alternative to reduce the use of chemical fertilizers in maize.展开更多
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201303057)948 Program(2011-G4)~~
文摘For exploring the influences of application and residue of chemical fungi- cides on chlamydospore preparations of Trichoderma spp., the effects of seven chemical fungicides on chlamydospore germination and mycelia growth of two bio- control fungi T. harzianum 610 and T. Iongibrachiatum 758 were studied. Carben- dazim, tebuconazole and difenoconazole showed strong toxicities, thiram and car- bexin showed moderate toxicities, and metalaxyl showed Mycelia growth of the two strains was more sensitive to most tested fungicides than those of chlamydospore germination. Chlamydospore germination of 610 was more sensitive to tested fungicides than those of 758, and mycelia growth of 758 was more sensitive to most tested fungi- cides than those of 610. Among the seven fungicides, 98% carbendazim had the strongest effects (ECru values were 1.64 and 0.05μpg/ml), and 70% pentachloroni- trobenzene had the weakest effects (EC50 values were 1.64 and 0,05 μg/ml) for chlamydospore germination and mycelia growth of 610. As for 758, 98% carbendaz- im had the strongest inhibitory effects and 95% metalaxyl had the weakest inhibitory for chlamydospore germination of 756 (EC50 values were 0.62 and 1 108.61 μg/ml respectively), whereas 96.2% tebuconazole showed the strongest inhibitory effects for mycelia growth of 758 (EC= value was 0.32μg/ml), and 95% metalaxyl was the weakest (EC= value was 1 206.29 μg/ml). According to the applied concentration of different fungicides in practice, we concluded that chlamydospore preparations of 610 and 758 could not be combined with carbendazim, tebuconazole, thiram and carboxin for controlling plant diseases, and the pesticide residues to the biocontrol effects should be kept in mind. Chlamydospore preparations of 610 and 758 can be and difenoconazole for controlling plant dis- eases, 758 chlamydospore preparations and germinated chlamydospore of 610 can be combined with metalaxyl for controlling plant diseases, and pesticide residue risk was not serious.
文摘[Objective] This study was conducted to investigate the effects of Penicillium spp. and Trichoderma spp. on the growth of Pleurotus ostreatus (oyster mushroom) and to screen effective disinfectants to control them and other pathogenic microbes. [Method] Six strains or species of Penicilliurn and Trichoderma were inocu- lated into PDA plates growing with P. ostreatus to observe the growth of their mycelia. And the inhibitory effects of hydrogen peroxide, bromogeramine bromide, 84 disinfectant, lysol, potassium permanganate, and 75% medical alcohol on Trichoderma pleuroticola, Trichoderma viride, Trichoderma harzianum, Penicillium citrinum, Penicillium thomii and Penicillium brevicompactum were detected. [Result] Confrontation test revealed that Penicillium spp. and Trichoderma spp. competed for nutrients with P. ostreatus mycelia, antagonized against the growth of P. ostreatus mycelia, invaded and twined around P. ostreatus mycelia, and also produced toxins poisoning P. ostreatus mycelia. The six disinfectants exhibited different inhibitory effects against different species of Penicillium and Trichoderma. Among them the in- hibitory effects of bromogeramine bromide against the six species of Penicillium and Trichoderma were significantly different. However, the inhibitory effects of 3% hydrogen peroxide, 84 disinfectant, 5% lysol, potassium permanganate and 75% medical alcohol were significantly different among Penicillium spp., but did not among Tri- choderma spp. [Conclusion] Bromogeramine bromide can be used to control the bacteria and fungi in mushroom production for it has significant inhibitory effects on the six species of both Penicillium and Trichoderma.
基金Supported by Chinese National Programs for High Technology Research and Development(2003AA241140)
文摘Trichoderma spp. is a filamentous soil fungus known as an effective biocontrol agent of a range of important airborne and soilborne pathogens, it has universal distribution and economic importance. This article reviewed the researches on biocontrol mechanism for plant diseases and application of Trichoderma spp., especially Trichoderma harzianum in recent years
文摘Different from ribosomal genes, which contain highly conserved sequences that are detected in all organisms, the intergenic spacer of rDNA (IGS) appears to be the most rapidly-evolving spacer region. For this reason we tested this region for phylogenetic studies. This report focuses on the study of IGS sequences of isolates belonging to Trichoderma section (T. viride, T. koningii, T. hamatum, T. erinaceus, T. asperellum) and Pachybasium section (T. harzianum, T. crassum, T. fasciculatum, T. oblongisporum, T. virens). Using the primer pair 28STD and CNS1, the Fast Start Taq DNA Polymerase (Roche), and a three temperature PCR protocol, products ranging from ca 1900 to 2400 bp were obtained from all tested isolates. The PCR product of 16 Trichoderma spp. isolates was cloned into a pGEM-TEeasy Vector (Promega) and sequenced. Based on a BLAST search we can conclude that the PCR product represents the whole IGS region. Multiple alignments of IGS sequences revealed two portions with different homology level. Portion A (ca 1660 bp) is the portion that contains 3’ end of 28S gene and is the more variable, while portion B (ca 830 bp), that contains the 3’ end of IGS region and the 5’ end of 18S gene, is the less variable. Comparing all sequences in region A 705 identical pairs occur out of 1704 total nucleotides (41.4%), while in region B identical pairs were 723 out of 832 total nucleotides (86.9%) . Sequence comparison of the two regions at intraspecific level (where it was possible) showed higher variability in region A (0.17%-6.8%) than in region B (0.0%-1.0%) . At interspecific level, performing all possible comparisons, the variability of region A (19.5%-52.7%) and B (0.8%- 16.9%). were significantly higher. Comparing sequences of species belonging to Trichoderma section variability of the two regions appears reduced if compared with that obtained from comparisons of species belonging to Pachybasium section. On the basis of sequence alignment, phylogenetic trees were obtained either with entire IGS, with region A, and with region B. Results of this analysis revealed that all isolates belonging to Trichoderma section grouped separately from isolates belonging to Pachybasium section. IGS region allowed us to group species according to their taxonomic position. The topology of the tree did not change substantially, varying in genetic distance only. Performing a GenBank search sequences representing the final portion of the IGS region of other fungal species were found, and we carried out a multiple alignment using also our sequences of Trichoderma spp. and Diaporthe helianthi. The phylogeny inferred from sequence alignment matched the generally accepted morphology-based classification and was identical to other molecular schemes at high taxonomic level. Data analysis was useful in establishing a broad-scale phylogeny of Ascomycota and was also useful in sorting them into statistically-supported clades. The tree showed that Trichoderma occurred in a well-supported terminal subclade of a larger clade that also contained other genera belonging to Hypocreales order. Sequence analysis of the Trichoderma spp. IGS region allowed us to design a specific PCR primer that was successfully used to amplify region A. The new reverse primer LCR2, that recognize all Trichoderma isolates, was identified in region B and confirmed for its specificity on the DNA of fungi belonging to other Ascomycota genera. Results obtained showed that IGS region seems to be an interesting and versatile tool for phylogenetic analysis, for resolving some taxonomic problems and for constructing specific primer useful for different purposes.
文摘The soil is a complex system where processes have direct influence on crop nutrition and plant health. Unfortunately, most of the agricultural soil management practices, compact them producing poor oxygenation, low benefic microorganism populations and metabolic disorders in plants. Those factors induce abnormal plant development and predisposition to the attack of soil borne plant pathogens as: Sclerotium cepivorum, Sclerotium rolfsi, Sclerotinia sclerotiorum, Rhizoctonia solani, Rosellinia spp. But also, some air borne pathogens as Colletotrichum sp., are more aggressive under those conditions. In Costa Rica some practical trails done by farmers, have shown that the addition of Trichoderma spp. to organic fertilizers like vermicompost, Bocashi, and other composts, has a positive effect on the structure and microbial diversity, that improves nutrient movement in plants and pathogen suppression. Vegetative material of leather fern (Rumohra adiantiformis) infected by Rosellinia spp., planted with bocashi amended with. T. asperellum (T. harzianum), showed more tip root growth and new fern rhizomes. Also the plants produced higher number of fiddleheads and high quality fronds. Non-treated material showed a total loss. In some leaf vegetables as lettuce the use of vermicompost followed by Trichoderma viride application, inhibited S. sclerotiorum development on the crop, in this study sclerotia were infected and plant yields were increased. Compost previously inoculated with Trichoderma, inhibited 100% the Botrytis and R. solani infection, in nurseries, and plant nutrition was improved. The observed results are attributed to the antagonistic effect of Trichoderma on soil and airborne pathogens, production of growth regulators, solubilization of some microelements and better mineral absorption with the development of more roots and elimination of diseased roots. As conclusion, the organic substrates inoculated with Trichoderma spp., besides the organic matter source, they improve the structural characteristics of soil, promote the biochemical processes, increases the level of growth regulator substances and inhibit plant disease as well.
文摘A series of highly taxonomically diverse Trichoderma strains were investigated using proteomic approaches, to investigate the utility of protein profiles as taxonomic markers and to identify proteins of potential economic importance. Initial studies have focused on a comparison of single strains of T. aureoviride, T. saturnisporum, T. polysporum, T. longbrachiatum and T. spirale, along with two strains of T. harzianum. All seven strains were grown in synthetic medium supplemented with 2%(w/v) glycerol, to maximize the diversity of extracellular protein production. Samples of secreted protein were separated by 2D gel electrophoresis and will be characterized by MALDI-TOF peptide fingerprinting.
文摘The study was conducted to determine the viability of producing organic onion under the fully converted area of Ramon Magsaysay Center for Agricultural Resources and Environment Studies (RMC-ARES), Central Luzon State University, Philippines. Specifically, the study aimed to establish the fi'equency of organic fertilizer and Trichoderma spp. application, employing split application, and determine the yield performance of red onion (bulb type). The research was conducted for two consecutive dry seasons (2014 and 2015). Red Creole variety was used with the following treatments: T1--organic fertilizer alone (8 ton/ha) at planting; T2--organic fertilizer (8 ton/ha) applied twice (at basal and 30 d after transplanting (DAT)); T3---organic fertilizer (8 ton/ha) applied twice (at basal and 30 DAT) + Trichoderma spp. at the rate of 526 kg/ha applied at planting; T4----organie fertilizer at 8 ton/ha rate + Trichoderma spp. at the rate of 526 kg/ha, both applied twice (at planting and 30 DAT); T5--organic fertilizer at 8 ton/ha rate applied twice (at planting and 30 DAT) + Trichoderma spp. at the rate of 526 kg/ha applied thrice (at planting, 30 DAT and during bulb formation). Results of the study showed that application of the recommended rate of organic fertilizer twice (at planting and 30 DAT) + three times application of Trichoderma spp. (at planting, 30 DAT and during bulb formation) consistently produced bigger bulb during the first and second trial of the study, compared to other treatments evaluated. Consequently, higher marketable yield was produced with 15.33 ton/ha during the first trial and 14.50 ton/ha on the second trial.
文摘Trichoderma spp. have been known for their strong abilities to produce extracellular enzymes, especially cellulases and glucanases by T. reesei, and also for their abilities to control plant pathogens. Most notably, a number of lines of evidence indicate that the agriculturally relevant strains are synergistic plant symbionts. As plant symbionts they possess the following characteristics: (a) they infect plant roots but cause the plant to restrict their growth to outer layers of the plant cortex (an exception is the recent discoveries of plant endophytic strains of Trichoderma and Gliocladium ), (b) they produce bioactive plant molecules in the zone of interaction that (c) induce localized systemic resistance to plant diseases and (d) systemic plant resistance to diseases that in some respects is similar to that induced by rhizobacteria, (e) they induce changes in plant proteomes, (f) increase plant growth and yield at least in part by enhancing root growth, and (g) they increase plant nutrient uptake. The increase in plant growth and yields is strongly interactive with plant genotype, at least in maize. There also are very significant increases in the knowledge of events that occur in mycoparasitism that in many respects have features in common with their interactions with plants. They are highly resistant to toxicants and have recently been shown to degrade cyanide and take up, and then degrade, metallocyanides. These discoveries allow new uses for the organisms in managed plant systems, including agriculture. For example, the induced systemic resistance system allows control of fungi, bacteria, Oomycetes and even one virus at sites temporally and spatially distant from the site of application. The abilities of the fungi to resist/degrade toxicants and increase plant growth indicate they will highly useful components in plant-microbe or microbe-only strategies for remediation of soil and water pollution. Finally, there are new uses of their enzyme systems for production of chitin degradation products for use as nutraceuticals or pharmaceuticals.
文摘Phytophthora species are particularly aggressive plant pathogens and are often associated with the decline of many tree species, including oak and beech. Several fungi and bacteria species are known as potential antagonists usable as biological control agents. Phosphonate (H3PO3), commonly branded as phosphite, has also been used in the past years to protect trees against invasive Phytophthora spp.. This study aimed at comparing the effects of selected antagonist microorganisms and phosphonate, when applied by microinjection or leaf treatment. Antagonistic species were first selected for their high inhibitory activity against problematic Phytophthora species, such as Phytophthora cactorum, P. quercina and P. plurivora attacking Quercus robur and Fagus sylvatica in Polish forests. Three endophytic species Trichoderma atroviride (two strains), T. harzianum and Bacillus amyloliquefaciens showed a high control activity, and their efficacy was then assessed in comparison with a phosphonate treatment. Two application methods were experimented in this study: injection of a solution of spores or phosphonate into the sap vessels of beech or a foliar treatment on oak. Phosphonate and two strains of Trichoderma significantly reduced the necrotic area on oak leaves inoculated with P. plurivora and one strain of T. atroviride significantly reduced necrotic areas on beech branches. These results are therefore promising of a novel way to control Phytophthora spp. in forest stands and nurseries.
文摘Variations in the radial growth rate of 24 isolates belonging to ten species of Trichoderma, three isolates of conifer pathogen Heterobasidion annosum s.s. and four isolates of H. parviporum were evaluated by incubation on a solid malt extract medium at a temperature of 4℃, 15℃ and 21℃. Trichoderma antagonism against Heterobasidion was investigated in dual culture in vitro. The slowest rate of growth was referable to all seven strains of Heterobasidion spp. All Heterobasidion spp. strains were overgrown by 63% of Trichoderma spp. strains after two weeks at 21℃ and by 33% of strains at 15℃. 21% of Trichoderma strains did not grow and only four strains belonging to T. koningii, T. viride and T. viridescens demonstrated the ability to completely overgrow Heterobasidion spp. after two weeks incubation at 4℃. According to the antagonistic efficiency, Trichoderma strains were divided into five groups with an Euclidean distance of 25. The groups contained isolates from different species. It was suggested that selected psychrotrophic fast growing T. viride, T. koningii and T. viridescens strains could be examined in different substrate conditions as suitable antagonist agents for the control of H. annosum and H. parviporum.
文摘Maize is the main crop for Mexicans;however, it is affected by species of fungi causing ear rot. This research aimed to evaluate the effect of T. asperellum T11, T. harzianum T1 4 y T. longibrachiatum T1 40 on some agronomic variables of four maize genotypes. The seeds of the genotypes H-515, Zapata 7, and H-507 were treated with a suspension of Trichoderma spp. to 1 × 10<sup>8</sup> spores mL<sup>-1</sup>, using a control (untreated seed), and Benomyl as chemical control. The planting was in Morelos, in a completely random block design with a factorial arrangement. The ear rot was natural. Data were obtained at the end of the crop cycle and processed in SAS 9.4<sup><sup>®</sup></sup>. H-515 genotype had the greatest effect on the treatment of maize seeds with Trichoderma spp. (5.562 kg);T. asperellum T11 was the strain that stood out with a mean yield of 50 ears in an area of 16 m<sup>2</sup> of 4.904 kg, and control of 4.448 kg. Our results are an economic option for farmers to contemplate the use of Trichoderma and obtain its benefits.
文摘Microbes that are beneficial to plants are used to enhance the crop growth,yield and are alternatives to chemical fertilizers.Trichoderma and Bacillus are the predominant plant growth-promoting fungi and bacteria.The objective of this study was select,characterize,and evaluate isolates of Trichoderma spp.and Bacillus spp.native from the northern region of Sinaloa,Mexico,and assess their effect on growth promotion in maize(Zea mays L.).In greenhouse conditions,four Trichoderma isolates and twenty Bacillus isolates,as well as two controls,were tested in a completely randomized design with three replicates.We selected the two best strains of Trichoderma and Bacillus:TB=Trichoderma asperellum,TF=Trichoderma virens,B14=Bacillus cereus sensu lato and B17=Bacillus cereus,which were evaluated in the field in a completely randomized blocks in factorial arrangement design with three replicates applying different rates of nitrogen fertilizer(0,150 kg N/ha,and 300 kg N/ha).Treatments 5(B17=B.cereus)and 11(TF=T.virens)both fertilized with 150 kg N/ha showed similar yields and they did not reveal significant differences from the treatments fertilized with 300 kg N/ha.This indicated that treatment 5(B17=B.cereus with 150 kg N/ha)and treatment 11(TF=T.virens with 150 kg N/ha)were efficient as growth promoters,by not showing significant differences in root volume and dry weight of foliage.The results indicated a reduction of 50% in the rate of nitrogen to fertilizer required for maize(Zea mays L.)crops.These microorganisms Trichoderma and Bacillus could be an alternative to reduce the use of chemical fertilizers in maize.