| expression of genes of trichoderma harzianum in response to the presence of cadmium in the substrate. | trichoderma harzianum is a very important fungus for the reduction of the amount of heavy metals resulting from agricultural and industrial activities. this filamentous fungus has been shown to be tolerant towards several heavy metals (e.g. cd, pb, zn, ni and mn), but the mechanism underlying this tolerance is not entirely understood. in this study, we confirmed the ability of t. harzianum to grow in the presence of cadmium and observed a significant stimulation of its growth in the presence of ... | 2012 | 22400914 |
| biochemical and physiological responses of rice (oryza sativa l.) as influenced by trichoderma harzianum under drought stress. | rice is one of the most important food crops drastically affected by drought in lowland rice ecosystems. in the present study, the impact of drought tolerant isolates of endophytic fungus trichoderma harzianum on rice response to drought was investigated. out of 43 trichoderma isolates studied, only five isolates viz., th 56, th 69, th 75, th 82 and th 89 were selected to be drought tolerant as these were able to colonize well on cow dung at low moisture content of 10-20 percent, though two isol ... | 2012 | 22391125 |
| monomeric l-amino acid oxidase-induced mitochondrial dysfunction in rhizoctonia solani reveals a novel antagonistic mechanism of trichoderma harzianum ets 323. | the monomeric l-amino acid oxidase (mth-laao) of trichoderma harzianum ets 323 has been suggested to antagonize rhizoctonia solani by an unknown mechanism. here, the mth-laao-treated r. solani exhibited hyphal lysis and apoptotic characteristics such as dna fragmentation, reactive oxygen species (ros) accumulation, lipid peroxidation, and mitochondrial membrane potential depolarization. this hyphal lysis was suppressed by the mitochondria-dependent apoptosis inhibitor oligomycin while accompanie ... | 2012 | 22352318 |
| transcriptomic response of arabidopsis thaliana after 24 h incubation with the biocontrol fungus trichoderma harzianum. | trichoderma harzianum is a fungus used as biocontrol agent using its antagonistic abilities against phytopathogenic fungi, although it has also direct effects on plants, increasing or accelerating their growth and resistance to diseases and the tolerance to abiotic stresses. we analyzed arabidopsis thaliana gene expression changes after 24 h of incubation in the presence of t. harzianum t34 using the affymetrix genechip arabidopsis ath1. because this microarray contains more than 22,500 probe se ... | 2012 | 22317785 |
| preparation, characterisation and viability of encapsulated trichoderma harzianum upm40 in alginate-montmorillonite clay. | microencapsulation is a process by which tiny parcels of an active ingredient are packaged within a second material for the purpose of shielding the active ingredient from the surrounding environment. this study aims to determine the ability of the microencapsulation technique to improve the viability of trichoderma harzianum upm40 originally isolated from healthy groundnut roots as effective biological control agents (bcas). alginate was used as the carrier for controlled release, and montmoril ... | 2012 | 22309479 |
| involvement of pachybasin and emodin in self-regulation of trichoderma harzianum mycoparasitic coiling. | our aim was to determine the effects of two secondary metabolites secreted by trichoderma harzianum, pachybasin and emodin, on the mycoparasitic coiling behavior and camp content of t. harzianum. the number of t. harzianum coils around nylon 66 fiber was increased in the presence of r. solani. the number of t. harzianum coils around r. solani hyphae and nylon 66 fiber were significantly increased in the presence of pachybasin and emodin. the camp level in t. harzianum was significantly increased ... | 2012 | 22292460 |
| arbuscular mycorrhizal protein mrna over-expression in bread wheat seedlings by trichoderma harzianum raifi (krl-ag2) elicitation. | association between arbuscular mycorrhizal fungi (amf) and majority of terrestrial plant species provides many benefits to plants that range from stress alleviation and bioremediation in soils polluted with heavy metals to plant growth promotion and yield quantity. some non-arbuscular mycorrhizal fungi such as, trichoderma harzianum, are known to enhance the amf symbiosis with vascular plants. however, information about their role in amf symbiosis is still limited. shoots of (avocet s) wheat see ... | 2012 | 22227493 |
| use of a new trichoderma harzianum strain isolated from the amazon rainforest with pretreated sugar cane bagasse for on-site cellulase production. | the on-site production of cellulases is an important strategy for the development of sustainable second-generation ethanol production processes. this study concerns the use of a specific cellulolytic enzyme complex for hydrolysis of pretreated sugar cane bagasse. glycosyl hydrolases (fpase, xylanase, and β-glucosidase) were produced using a new strain of trichoderma harzianum, isolated from the amazon rainforest and cultivated under different conditions. the influence of the carbon source was fi ... | 2012 | 22221990 |
| biological control of rice brown spot with native isolates of three trichoderma species. | brown spot caused by bipolaris oryzae is an important rice disease in southern coast of caspian sea, the major rice growing region in iran. a total of 45 trichoderma isolates were obtained from rice paddy fields in golestan and mazandaran provinces which belonged to trichoderma harzianum, t. virens and t. atroviride species. initially, they were screened against b. oryzae by antagonism tests including dual culture, volatile and nonvolatile metabolites and hyperparasitism. results showed that tri ... | 2012 | 24031832 |
| effect of ph and temperature on the global compactness, structure, and activity of cellobiohydrolase cel7a from trichoderma harzianum. | due to its elevated cellulolytic activity, the filamentous fungus trichoderma harzianum (t. harzianum) has considerable potential in biomass hydrolysis application. cellulases from trichoderma reesei have been widely used in studies of cellulose breakdown. however, cellulases from t. harzianum are less-studied enzymes that have not been characterized biophysically and biochemically as yet. here, we examined the effects of ph and temperature on the secondary and tertiary structures, compactness, ... | 2012 | 22048567 |
| the qid74 gene from trichoderma harzianum has a role in root architecture and plant biofertilization. | the trichoderma harzianum qid74 gene encodes a cysteine-rich cell wall protein that has an important role in adherence to hydrophobic surfaces and cellular protection; this gene was upregulated in trichoderma high-density oligonucleotide (hdo) microarrays in interaction with tomato roots. using a collection of qid74-overexpressing and disrupted mutants the role of this gene in cucumber and tomato root architecture was analysed in hydroponic and soil systems under greenhouse conditions. no signif ... | 2012 | 21948047 |
| purification, and biochemical and biophysical characterization of cellobiohydrolase i from trichoderma harzianum ioc 3844. | because of its elevated cellulolytic activity, the filamentous fungus trichoderma harzianum has a considerable potential in biomass hydrolysis applications. trichoderma harzianum cellobiohydrolase i (thcbhi), an exoglucanase, is an important enzyme in the process of cellulose degradation. here, we report an easy single-step ion-exchange chromatographic method for purification of thcbhi and its initial biophysical and biochemical characterization. the thcbhi produced by induction with microcrysta ... | 2011 | 21876370 |
| hydroxylation modification and free radical scavenging activity of puerarin-7-o-fructoside. | puerarin-7-o-fructoside was transformed by trichoderma harzianum cgmcc 1523 into 3'-hydroxypuerarin-7-o-fructoside; this was identified by ms and nmr. however, puerarin-7-o-glucoside was not directly hydroxylated but hydrolyzed back into puerarin, which was transformed into 3'-hydroxypuerarin by the same fungi. comparative analysis of free radical scavenging activity of dpph showed that the free radical scavenging activity of puerarin-7-o-glucoside was reduced to approximately 1/2 of that of pue ... | 2011 | 21818614 |
| biotechnological applications of the gene transfer from the beneficial fungus trichoderma harzianum spp. to plants. | alternative and ecological strategies are necessary and demanded for disease management in order to reduce the use of pesticides in agriculture. thus, the use of biological control agents such as plant growth-promoting rhizobacteria (pgpr) or several strains of the beneficial fungus trichoderma spp. to combat plant diseases is the basis of biocontrol of plant pathogens and is a good approach to reach this healthy and environmentally adequate objective. | 2011 | 21772122 |
| trichoderma harzianum might impact phosphorus transport by arbuscular mycorrhizal fungi. | trichoderma sp. is a biocontrol agent active against plant pathogens via mechanisms such as mycoparasitism. recently, it was demonstrated that trichoderma harzianum was able to parasitize the mycelium of an arbuscular mycorrhizal (am) fungus, thus affecting its viability. here, we question whether this mycoparasitism may reduce the capacity of glomus sp. to transport phosphorus ((33)p) to its host plant in an in vitro culture system. (33)p was measured in the plant and in the fungal mycelium in ... | 2011 | 21609342 |
| comparison of real-time pcr and microscopy to evaluate sclerotial colonisation by a biocontrol fungus. | the biocontrol agent trichoderma harzianum colonises sclerotia of the plant pathogenic fungus sclerotinia sclerotiorum. plating of sclerotia typically has been used to determine the incidence of mycoparasitism, but does not quantify the extent to which individual sclerotia are colonised. we developed a specific pcr primer/probe set for the green fluorescent protein (gfp)-transformant t. harzianum thzid1-m3, which exhibited high precision and reproducibility. quantitative real-time pcr was evalua ... | 2011 | 21530913 |
| co-entrapment of trichoderma harzianum and glomus sp. within alginate beads: impact on the arbuscular mycorrhizal fungi life cycle. | this study was performed to explore the compatibility and applicability of plant beneficial micro-organisms (i.e. trichoderma harzianum mucl 29707 and glomus sp. mucl 41833) co-entrapped in alginate beads. | 2011 | 21518156 |
| trichoderma harzianum strain sqr-t37 and its bio-organic fertilizer could control rhizoctonia solani damping-off disease in cucumber seedlings mainly by the mycoparasitism. | damping-off disease is caused by rhizoctonia solani and leads to serious loss in many crops. biological control is an efficient and environmentally friendly way to prevent damping-off disease. optical micrographs, scanning electron micrographs, and the determination of hydrolytic enzymes were used to investigate the antagonism of trichoderma harzianum sqr-t37 (sqr-t37) against r. solani. experiments were performed in pots to assess the in vivo disease-control efficiency of sqr-t37 and bio-organi ... | 2011 | 21484203 |
| the overexpression in arabidopsis thaliana of a trichoderma harzianum gene that modulates glucosidase activity, and enhances tolerance to salt and osmotic stresses. | using the trichoest database, generated in a previous functional genomics project from the beneficial filamentous fungus trichoderma harzianum, a gene named thkel1, which codes for a putative kelch-repeat protein, was isolated and characterized. silencing of this gene in t. harzianum leads to a reduction of glucosidase activity and mycelial growth under abiotic stress conditions. expression of this gene in arabidopsis enhances plant tolerance to salt and osmotic stresses, accompanied by an incre ... | 2011 | 21466906 |
| a novel l-amino acid oxidase from trichoderma harzianum ets 323 associated with antagonism of rhizoctonia solani. | trichoderma spp. are used as biocontrol agents against phytopathogens such as rhizoctonia solani, but their biocontrol mechanisms are poorly understood. a novel l-amino oxidase (th-laao) was identified from the extracellular proteins of trichoderma harzianum ets 323. here, we show a fad-binding glycoprotein with the best substrate specificity constant for l-phenylalanine. although the amino acid sequence of th-laao revealed limited homology (16-24%) to other laao members, a highly conserved fad- ... | 2011 | 21456553 |
| role of the morphology and polyphosphate in trichoderma harzianum related to cadmium removal. | this study concerns the metabolism of polyphosphate in trichoderma harzianum, a biocontrol agent with innate resistance against most chemicals used in agriculture, including metals, when grown in the presence of different concentrations of cadmium. the biomass production was affected by the concentration of metal used. control cultures were able to accumulate polyphosphate under the conditions used. moreover, the presence of cadmium induced a reduction in polyphosphate content related to the con ... | 2011 | 21407149 |
| strain-specific scar markers for the detection of trichoderma harzianum as12-2, a biological control agent against rhizoctonia solani, the causal agent of rice sheath blight. | in order to identify a specific marker for t. harzianum as12-2, a strain capable of controlling rice sheath blight caused by rhizoctonia solani, up-pcr was performed using five universal primers (up) both separately and in pairwise combinations. the application of two up primers resulted in the amplification of unique fragments from the genomic dna of t. harzianum as12-2, clearly distinguishing it from other trichoderma strains. the unique fragments had no significant sequence homology with any ... | 2011 | 21388921 |
| differential expression of oil palm pathology genes during interactions with ganoderma boninense and trichoderma harzianum. | the expression profiles of δ9 stearoyl-acyl carrier protein desaturase (sad1 and sad2) and type 3 metallothionein (mt3-a and mt3-b) were investigated in seedlings of oil palm (elaeis guineensis) artificially inoculated with the pathogenic fungus ganoderma boninense and the symbiotic fungus trichoderma harzianum. expression of sad1 and mt3-a in roots and sad2 in leaves were significantly up-regulated in g. boninense inoculated seedlings at 21 d after treatment when physical symptoms had not yet a ... | 2011 | 21333381 |
| expression and characterization of two new alkane-inducible cytochrome p450s from trichoderma harzianum. | n-dodecane and fatty acids were good inducers of cytochrome p450 (cyp) and the ω-hydroxylase of lauric acid, which is a marker for ω-hydroxylation of n-alkanes, in trichoderma harzianum. a cdna, containing an orf of 1520 bp, encoding a cyp52 of 520 amino acids, was isolated by race. another n-alkane-inducible cyp was identified by llc-ms/ms analysis of a microsomal protein band induced by n-dodecane in a library of t. harzianum. this suggests that t. harzianum has a cyp-dependent conversion of a ... | 2011 | 21327702 |
| [investigation of antitumor substance from trichoderma]. | the effect of l-lysine-alpha-oxidase from trichoderma harzianum rifai on the functional activity of t-lymphocytes was investigated. it was shown that in a dose of 35 units/kg administered parentally the enzyme had no suppressive effect on the t-lymphocyte functional activity. an inhibitory effect of l-lysine-a-oxidase on some indices of the macrophages functional activity was observed. l-lyzine-alpha-oxidase had a selective lymphotropic action and showed no mytostatic activity, which is in favou ... | 2011 | 22586896 |
| the interaction with arbuscular mycorrhizal fungi or trichoderma harzianum alters the shoot hormonal profile in melon plants. | arbuscular mycorrhizal fungi (amf) and trichoderma harzianum are known to affect plant growth and disease resistance through interaction with phytohormone synthesis or transport in the plant. cross-talk between these microorganisms and their host plants normally occurs in nature and may affect plant resistance. simultaneous quantification in the shoots of melon plants revealed significant changes in the levels of several hormones in response to inoculation with t. harzianum and two different amf ... | 2011 | 21145086 |
| high-yield endoglucanase production by trichoderma harzianum ioc-3844 cultivated in pretreated sugarcane mill byproduct. | the low-cost production of cellulolytic complexes presenting high action at mild conditions and well-balanced cellulase activities is one of the major bottlenecks for the economical viability of the production of cellulosic ethanol. in the present paper, the filamentous fungus trichoderma harzianum ioc-3844 was used for the production of cellulases from a pretreated sugarcane bagasse (namely, cellulignin), by submerged fermentation. this fungal strain produced high contents of endoglucanase acti ... | 2010 | 21048871 |
| trichoderma harzianum sqr-t037 rapidly degrades allelochemicals in rhizospheres of continuously cropped cucumbers. | to alleviate the stress of continuous cropping for cucumber continuous cropping (ccc) system, a beneficial fungus trichoderma harzianum sqr-t037 (sqr-t037) was isolated and applied to soil to degrade allelochemicals exuded from cucumber plants in a rhizobox experiment. the following phenolic acids (pas), classified as allelochemicals, were isolated and identified from cucumber rhizospheres: 4-hydroxybenzoic acid, vanillic acid, ferulic acid, benzoic acid, 3-phenylpropionic acid, and cinnamic aci ... | 2011 | 20972783 |
| isozyme analysis and relationships among three species in malaysian trichoderma isolates. | isozyme and protein electrophoresis data from mycelial extracts of 27 isolates of trichoderma harzianum, 10 isolates of t. aureoviride and 10 isolates of t. longibrachiatum from southern peninsular malaysia were investigated. the eight enzyme and a single protein pattern systems were analyzed. three isozyme and total protein patterns were shown to be useful for the detection of three trichoderma species. the isozyme and protein data were analyzed using the nei and li dice similarity coefficient ... | 2010 | 20890090 |
| purification, crystallization and preliminary crystallographic analysis of the catalytic domain of the extracellular cellulase cbhi from trichoderma harzianum. | the filamentous fungus trichoderma harzianum has a considerable cellulolytic activity that is mediated by a complex of enzymes which are essential for the hydrolysis of microcrystalline cellulose. these enzymes were produced by the induction of t. harzianum with microcrystalline cellulose (avicel) under submerged fermentation in a bioreactor. the catalytic core domain (ccd) of cellobiohydrolase i (cbhi) was purified from the extracellular extracts and submitted to robotic crystallization. diffra ... | 2010 | 20823521 |
| purification and characterization of novel glucanases from trichoderma harzianum ets 323. | trichoderma harzianum ets 323 secretes two glucanases, a 23.5 kda endoglucanase (eg th1) and a 61 kda exoglucanase (exg th1). they were identified by their hydrolysis products and were purified to homogeneity. the optimal temperature and ph for both eg th1 (7.3-fold purification, 5.0% yield) and exg th1 (33.7-fold purification, 0.15% yield) were 50 °c and ph 4.5, respectively. the kinetic parameters of eg th1 (k(m) = 23 mg ml(-1), v(max) = 294 μm min(-1), specific activity = 7.4 u mg(-1)) and ex ... | 2010 | 20815353 |
| seed treatment with trichoderma harzianum alleviates biotic, abiotic, and physiological stresses in germinating seeds and seedlings. | trichoderma spp. are endophytic plant symbionts that are widely used as seed treatments to control diseases and to enhance plant growth and yield. although some recent work has been published on their abilities to alleviate abiotic stresses, specific knowledge of mechanisms, abilities to control multiple plant stress factors, their effects on seed and seedlings is lacking. we examined the effects of seed treatment with t. harzianum strain t22 on germination of seed exposed to biotic stress (seed ... | 2010 | 20649416 |
| a comparison of preservation methods for trichoderma harzianum cultures. | | 2012 | 20624479 |
| mycoparasitism of arbuscular mycorrhizal fungi: a pathway for the entry of saprotrophic fungi into roots. | within the rhizosphere, arbuscular mycorrhizal (am) fungi interact with a cohort of microorganisms, among which is the biological control agent, trichoderma spp. this fungus parasitizes a wide range of phytopathogenic fungi, a phenomenon also reported in the extraradical mycelium (erm) of am fungi. here, we question whether the mycoparasitism of the erm could be extended to the intraradical mycelium (irm), thus representing a pathway for the entry of trichoderma harzianum within the root. microc ... | 2010 | 20533946 |
| purification and characterization of an acid phosphatase from trichoderma harzianum. | an acid phosphatase from trichoderma harzianum was purified in a single step using a phenyl-sepharose chromatography column. a typical procedure showed 22-fold purification with 56% yield. the purified enzyme showed as a single band on sds-page with an apparent molecular weight of 57.8 kda. the ph optimum was 4.8 and maximum activity was obtained at 55 degrees c. the enzyme retained 60% of its activity after incubation at 55 degrees c for 60 min. the k (m) and v (max) values for p-nitrophenyl ph ... | 2010 | 20364293 |
| solid-state cultivation of trichoderma harzianum nbri-1055 for modulating natural antioxidants in soybean seed matrix. | trichoderma harzianum nbri-1055 was used, as fungal candidate to enhance the antioxidant activities of soybean matrix by modulating polyphenolic substances during solid-state fermentation. trichoderma-fermented soybean (tfs) and unfermented soybean (ufs) products were extracted with water (w) and methanol (m). total phenolic content of tfs-w and tfs-m extracts were significantly higher than that of ufs-w and ufs-m extracts. the effectiveness of extracts for total flavonoid content, antioxidant a ... | 2010 | 20363120 |
| transcriptome and metabolome profiling of field-grown transgenic barley lack induced differences but show cultivar-specific variances. | the aim of the present study was to assess possible adverse effects of transgene expression in leaves of field-grown barley relative to the influence of genetic background and the effect of plant interaction with arbuscular mycorrhizal fungi. we conducted transcript profiling, metabolome profiling, and metabolic fingerprinting of wild-type accessions and barley transgenics with seed-specific expression of (1,3-1, 4)-beta-glucanase (glub) in baronesse (b) as well as of transgenics in golden promi ... | 2010 | 20308540 |
| transgenic expression of the trichoderma harzianum hsp70 gene increases arabidopsis resistance to heat and other abiotic stresses. | the ability of some trichoderma strains, a biological control agent, to overcome extreme environmental conditions has previously been reported and related to heat-shock proteins (hsps). these proteins are induced environmentally and are involved in important processes, acting as molecular chaperones in all organisms. in a previous study, we demonstrated, by overexpression, that the trichoderma harzianum hsp70 gene conferred tolerance to heat and other abiotic stresses to this fungus. in this wor ... | 2010 | 20080316 |
| regeneration and molecular characterization of an intergeneric hybrid between graphium putredinis and trichoderma harzianum by protoplasmic fusion. | the fungal strains graphium putredinis and trichoderma harzianum were selected as parents for fusant development. protoplasts were isolated using the combination of lysing enzymes novozym 234 and cellulase with 0.6m kcl as osmotic stabilizer. the optimum conditions for release of viable protoplasts from the fungal mycelium viz. age of the mycelium, lytic enzymes, osmotic stabilizers, ph, incubation period and regeneration medium were determined. intergeneric protoplast fusion was carried out usi ... | 2010 | 20064604 |
| electrochemical dna biosensor for the detection of specific gene related to trichoderma harzianum species. | a new electrochemical biosensor is described for voltammetric detection of gene sequence related to trichoderma harzianum. the sensor involves immobilization of a 20 base single-stranded probe (ssdna), which is complementary to a specific gene sequence related to t. harzianum on a gold electrode through specific adsorption. the dna probe was used to determine the amount of target gene in solution using methylene blue (mb) as the electrochemical indicator. the covalently immobilized probe could s ... | 2010 | 19945357 |
| quantification of the biocontrol agent trichoderma harzianum with real-time taqman pcr and its potential extrapolation to the hyphal biomass. | the species of the genus trichoderma are used successfully as biocontrol agents against a wide range of phytopathogenic fungi. among them, trichoderma harzianum is especially effective. however, to develop more effective fungal biocontrol strategies in organic substrates and soil, tools for monitoring the control agents are required. real-time pcr is potentially an effective tool for the quantification of fungi in environmental samples. the aim of this study consisted of the development and appl ... | 2010 | 19897358 |
| gene expression analysis of the biocontrol fungus trichoderma harzianum in the presence of tomato plants, chitin, or glucose using a high-density oligonucleotide microarray. | it has recently been shown that the trichoderma fungal species used for biocontrol of plant diseases are capable of interacting with plant roots directly, behaving as symbiotic microorganisms. with a view to providing further information at transcriptomic level about the early response of trichoderma to a host plant, we developed a high-density oligonucleotide (hdo) microarray encompassing 14,081 expressed sequence tag (est)-based transcripts from eight trichoderma spp. and 9,121 genome-derived ... | 2009 | 19825185 |
| study on the anthraquinones separated from the cultivation of trichoderma harzianum strain th-r16 and their biological activity. | the biocontrol fungal species of trichoderma, which colonizes plant roots, are well-known for their potential to control plant pathogens. six anthraquinones, of which four have been identified for the first time from trichoderma and two have already been reported in other strains, were purified from trichoderma harzianum strain th-r16 to evaluate their biological activities. the structures of the compounds were determined by one- and two-dimensional nmr. the compounds were shown to exhibit stron ... | 2009 | 19650641 |
| toward understanding of carbohydrate binding and substrate specificity of a glycosyl hydrolase 18 family (gh-18) chitinase from trichoderma harzianum. | surface plasmon resonance (spr) has been used to assay the roles of amino acid residues in the substrate binding cleft of trichoderma harzianum chitinase chit42, which belongs to the glycoside hydrolase family 18 (gh-18). nine different chit42 variants having amino acid mutations along the binding site cleft at subsites -4 to +2 were created and characterized with regard to their affinity toward chitinous and non-chitinous oligosaccharides. the catalytically inactive chit42 mutant e172q was used ... | 2009 | 19596709 |
| biotransformation of steriodal saponins in dioscorea zingiberensis c. h. wright to diosgenin by trichoderma harzianum. | diosgenin is an important starting material in the steroidal hormone industry. traditionally, diosgenin is mainly produced by acid hydrolysis of dioscorea zingiberensis c. h. wright (dzw) tubers. this method yields numerous byproducts that can cause serious pollution. in this study, diosgenin was obtained by biotransformation of steroidal saponins in dzw afforded by trichoderma harzianum cgmcc 2979. the medium was optimized for maximum diosgenin production. the addition of phosphate buffer, surf ... | 2010 | 19578845 |
| improvement of growth of eucalyptus globulus and soil biological parameters by amendment with sewage sludge and inoculation with arbuscular mycorrhizal and saprobe fungi. | sewage sludge is widely used as an organic soil amendment to improve soil fertility. we investigated the effects of sewage sludge (ss) application on certain biological parameters of eucalyptus globulus labill. the plant was either uninoculated or inoculated with saprobe fungi (coriolopsis rigida and trichoderma harzianum) or arbuscular mycorrhizal (am) fungi (glomus deserticola and gigaspora rosea). sewage sludge was applied to the surface of experimental plots at rates of 0, 2, 4, 6 and 8 g 10 ... | 2009 | 19515400 |
| removal and recovery of uranium from aqueous solutions by ca-alginate immobilized trichoderma harzianum. | the ability of ca-alginate immobilized trichoderma harzianum has been explored for removal and recovery of uranium from aqueous streams. ca-alginate as polymeric support was selected after screening different matrices. immobilization of trichoderma harzianum to ca-alginate improved the stability as well as uranium biosorption capacity of biosorbent at 28+/-2 degrees c and 200 rpm. the suitability of packed bed column operations was illustrated by obtaining break through curves at different bed h ... | 2009 | 19467596 |
| implications of cysteine metabolism in the heavy metal response in trichoderma harzianum and in three fusarium species. | we studied the ability of four different fungal species, trichoderma harzianum, fusarium antophyllum, fusarium compactum and fusarium phyllophilum, to grow in the presence of heavy metals, and monitored their cysteine and glutathione content and the activity of o-acetylserine(thiol)lyase (oastl), which is involved in cysteine biosynthesis. zn and pb did not affect fungal growth or sporulation at the concentrations used, whereas cd and hg did. in most cases, cysteine and glutathione content was h ... | 2009 | 19298998 |
| mycorrhizal fungi and trichoderma harzianum as biocontrol agents for suppression of rhizoctonia solani damping-off disease of tomato. | the objective of the present work was to examine the interaction between arbuscular mycorrhizal fungus (amf) glomus intraradices and trichoderma harzianum in soil. soil application with t. harzianum or/and g. intraradices significantly reduced tomato seedlings damping-off incited by rhizoctonia solani. moreover, more pronounced disease suppression was obtained when both bioagents were applied together. application of t. harzianum to healthy or inoculated seedlings significantly increased phospho ... | 2008 | 19226759 |
| fatal trichoderma harzianum infection in a leukemic pediatric patient. | we report the repeated isolation for trichoderma.harzianum, a rare opportunistic pathogen from three sets of each of the following clinical samples; blood serum, skin lesions, sputum and throat of a pediatric all patient with neutropenia. the definition of invasive fungal infection requires evidence of the presence of fungal elements in tissue samples, in addition to the isolation of suspected etiologic agent in culture. however, invasive procedures are not always applicable due to several facto ... | 2009 | 19169948 |
| in vitro antagonistic characteristics of bacilli isolates against trichoderma spp. and three species of mushrooms. | twenty isolates of bacillus species obtained from livestock manure composts and cotton-waste composts were tested for their antagonistic effects in vitro against three green mold pathogens of mushrooms (trichoderma harzianum, t. koningii, and t. viridescens). however, there exists a possibility bacillus species may have antagonistic effects against mushrooms themselves, and thus the same 20 isolates were tested in vitro against three species of mushrooms (flammulina velutipes, lentinus edodes, a ... | 2008 | 23997638 |
| cloning and characterization of the thcut1 gene encoding a cutinase of trichoderma harzianum t34. | the cloning and characterization of the thcut1 gene, which encodes a cutinase protein of the biocontrol fungus trichoderma harzianum t34, is reported. cutinases, which are secreted enzymes that hydrolyse cutin, belong to a class of serine esterases able to hydrolyze fatty acid esters and emulsified triglycerides. the thcut1 gene was isolated by screening of a genomic dna library from est 2104, generated from a t. harzianum t34 cdna library constructed under mycoparasitic and nutrient stress cond ... | 2008 | 18987860 |
| ecological studies of transformed trichoderma harzianum strain 1295-22 in the rhizosphere and on the phylloplane of creeping bentgrass. | abstract a beta-glucuronidase (gus) reporter gene and a hygromycin b (hygb) phosphotransferase gene were integrated separately into the trichoderma harzianum strain 1295-22 genome, using biolistic transformation. the mycelial growth and biocontrol ability of the transformed strains did not differ from that of the original strain. the transformed gus(+)-kanamycin-resistant (gus(+)kan(r)) strains were used to monitor growth and interactions with rhizoctonia solani on creeping bentgrass plants. the ... | 1998 | 18944981 |
| molecular phylogenetic analyses of biological control strains of trichoderma harzianum and other biotypes of trichoderma spp. associated with mushroom green mold. | abstract a polymerase chain reaction-amplified dna containing the internal transcribed spacer (its)-1, 5.8s, and its-2 regions of the nuclear ribosomal dna transcriptional unit was sequenced for 81 isolates of trichoderma spp. associated with mushroom culture or used for biological control of plant pathogens. phylogenetic analyses revealed that the biocontrol isolates were more closely related to an isolate of t. harzianum biotype 1 (th1) than to the aggressive biotypes 2 and 4. th1 has been iso ... | 1999 | 18944776 |
| increased antifungal activity of trichoderma harzianum transformants that overexpress a 33-kda chitinase. | abstract transformants of the biocontrol agent trichoderma harzianum strain cect 2413 that overexpressed a 33-kda chitinase (chit33) were obtained and characterized. strain cect 2413 was cotransformed with the amds gene and its own chit33 gene under the control of the pki constitutive promoter from t. reesei. southern blotting indicated that the chit33 gene was integrated ectopically, mostly in tandem. some transformants showed the same restriction pattern, indicating preferable sites of integra ... | 1999 | 18944767 |
| use of green fluorescent protein and image analysis to quantify proliferation of trichoderma harzianum in nonsterile soil. | abstract one drawback of traditional methods for fungal biomass measurement is the inability to distinguish biomass of an introduced fungus from that of the indigenous microbial community in nonsterile soil. we quantified biomass of a specific fungal biological control agent in nonsterile soil using epifluorescence microscopy and image analysis of green fluorescent protein (gfp)-expressing trichoderma harzianum (thzid1-m3). numbers of colony forming units on a semiselective medium were compared ... | 2004 | 18943710 |
| individual-based approach to modeling hyphal growth of a biocontrol fungus in soil. | abstract fungi in soil perform beneficial roles that include biological control of soilborne plant pathogens. however, relatively little predictive information is available about the growth and activity of fungal hyphae in soil habitats. a stochastic computer simulation model ("fungmod") was developed to predict hyphal growth of the biocontrol fungus trichoderma harzianum thzid1 in soil. the model simulates a fungal colony as a population of spatially referenced hyphal segments, and is individua ... | 2006 | 18943499 |
| influence of a fungus-feeding nematode on growth and biocontrol efficacy of trichoderma harzianum. | abstract a fungivorous nematode, aphelenchoides sp., was isolated from field soil by baiting with mycelium of the biocontrol fungus trichoderma harzianum thzid1, and subsequently was maintained on agar cultures of the fungus. interactions between the nematode and the green fluorescent protein-producing transformant, t. harzianum thzid1-m3, were investigated in both heat-treated (80 degrees c, 30 min) and untreated field soil. thzid1-m3 was identified in soil by epifluorescence microscopy. when t ... | 2001 | 18943350 |
| amendment with peony root bark improves the biocontrol efficacy of trichoderma harzianum against rhizoctonia solani. | we tested trichoderma harzianum as a biocontrol agent for rhizoctonia solani ag2-1, using six natural antifungal materials to improve its efficacy. among the six materials tested, peony (paeonia suffruticosa) root bark (prb) showed the strongest antifungal activity against r. solani ag2-1, and was not antagonistic to t. harzianum. scanning electron microscopy showed that treatment with prb extract resulted in shortened and deformed r. solani ag2-1 hyphal cells. the control of radish damping-off ... | 2008 | 18852509 |
| overexpression of a trichoderma hsp70 gene increases fungal resistance to heat and other abiotic stresses. | all organisms share similar mechanisms in the heat shock response, such as synthesis of conserved heat shock proteins. here, we report on the cloning, characterization and functional analysis of a trichoderma harzianum t34 hsp70 gene. the expression of this gene was evaluated in cultures grown in abiotic stress conditions. an increased level of expression was detected when the fungus was grown at 37 or 41 degrees c, as well as in the presence of oxidative or osmotic agents. the overexpression of ... | 2008 | 18824239 |
| production of 6-pentyl-α-pyrone by trichoderma harzianum in solid-state fermentation. | many trichoderma species are able to produce 6-pentyl-α-pyrone (6-pp), a lactone with coconut-like aroma. in the present work, several culture parameters were studied to enhance the production of 6-pp by trichoderma harzianum 4040 in solid-state fermentation. green coir powder added to a nutrient solution was used as support material for fermentation. a plackett-burman screening technique was applied, followed by a fractionary factorial design. the best culture conditions within the experimental ... | 2008 | 24031295 |
| induction of beta-1,3-glucanase in callus cultures in vitro. | sodium salicylate (nasa) increased induction of both intracellular and extracellular beta-1,3-glucanases in calluses of campion and duckweed. nasa concentrations from 30 to 100 mm were optimal for induction of intracellular glucanase in the campion callus, and for induction of extracellular glucanase the optimal concentration varied from 5 to 100 mm. the glucanase activity in the duckweed callus was lower than in the campion callus, and co-cultivation of the campion callus with trichoderma harzi ... | 2008 | 18707591 |
| proteomic study of biocontrol mechanisms of trichoderma harzianum ets 323 in response to rhizoctonia solani. | to elucidate the entire range of proteins that are secreted by trichoderma harzianum ets 323 in its antagonism with rhizoctonia solani, an in vivo interaction between them was mimicked and not only the secreted cell wall-degrading enzymes (cwdes) but also all of the proteome were investigated. seven cwdes, chitinase, cellulase, xylanase, beta-1,3-glucanase, beta-1,6-glucanase, mannanase, and protease,were revealed by activity assay, in-gel activity stain, 2-de, and lc-ms/ms analysis. extracellul ... | 2008 | 18642836 |
| the molecular basis of shoot responses of maize seedlings to trichoderma harzianum t22 inoculation of the root: a proteomic approach. | trichoderma spp. are effective biocontrol agents for several soil-borne plant pathogens, and some are also known for their abilities to enhance systemic resistance to plant diseases and overall plant growth. root colonization with trichoderma harzianum rifai strain 22 (t22) induces large changes in the proteome of shoots of maize (zea mays) seedlings, even though t22 is present only on roots. we chose a proteomic approach to analyze those changes and identify pathways and genes that are involved ... | 2008 | 18562766 |
| genome-wide identification, expression and chromosomal location of the genes encoding chitinolytic enzymes in zea mays. | chitinolytic enzymes are important pathogenesis and stress related proteins. we identified 27 putative genes encoding endochitinases in the maize genome via in silico techniques and four exochitinases. only seven of the endochitinases and segments of the exochitinases were heretofore known. the endochitinases included members of family 19 chitinases (classes i-iv of pr3, ii of pr4) and members of family 18 chitinases (class iii of pr8). some similar enzymes were detected on adjacent regions of t ... | 2008 | 18560892 |
| water deficit as a driver of the mutualistic relationship between the fungus trichoderma harzianum and two wheat genotypes. | the aim of this study was to assess the occurrence of mutualistic interactions between the fungus trichoderma harzianum and two wheat genotypes, triticum aestivum cv. talhuén and t. turgidum subsp. durum cv. alifén, and the extent to which water deficit affected these interactions. two wheat genotypes were cultivated in the presence or absence of t. harzianum and in the presence or absence of water deficit. t. harzianum was in turn cultivated in the presence or absence of wheat plants and in the ... | 2008 | 18192424 |
| effects of mutual interaction of laccaria laccata with trichoderma harzianum and t. virens on the morphology of microtubules and mitochondria. | organelles are known to respond to challenges caused by many stress factors. the morphology of the microtubular cytoskeleton and mitochondria during mutual interaction in coculture of laccaria laccata with trichoderma harzianum and t. virens were examined. hyphae from the interaction region were sampled between 4 and 12 days of growth. microtubules were labelled with a specific antibody and mitochondria with 3,3'-dihexyloxacarbocyanine iodide, and the organelles were examined microscopically. th ... | 2007 | 18176836 |
| statistical optimization of process conditions for cellulase production by liquid state bioconversion of domestic wastewater sludge. | a two-level fractional factorial design (ffd) was used to determine the effects of six factors, i.e. substrate (domestic wastewater sludge - dws) and co-substrate concentration (wheat flour - wf), temperature, initial ph, inoculum size and agitation rate on the production of cellulase enzyme by trichoderma harzianum in liquid state bioconversion. on statistical analysis of the results from the experimental studies, optimum process conditions were found to be temperature 32.5 degrees c, substrate ... | 2008 | 17981027 |
| ph and pac1 control development and antifungal activity in trichoderma harzianum. | in trichoderma harzianum cect 2413 external ph regulates essential functions such as growth rate, sporulation, cell and colony morphology, pattern of secreted proteins, gene expression or mycoparasitism-related enzymatic activities. ph regulation is mediated by the transcriptional factor pac1 (homologous to pacc regulator in other fungi), encoded by pac1 whose expression increases with ph. two pac1 mutants have been obtained from cect 2413: p2.32, that possesses an allele of pac1 active at any p ... | 2007 | 17881256 |
| effect of diatomaceous earth and trichoderma harzianum t-22 (rifai strain krl-ag2) on the fungus gnat bradysia sp. nr. coprophila (diptera: sciaridae). | this study, consisting of three experiments, was designed to assess whether diatomaceous earth, when applied to the surface of growing media, reduces adult fungus gnat bradysia sp. nr. coprophila (diptera: sciaridae) emergence or inhibits the females from laying eggs; and whether fungus gnat adults are attracted to the fungus trichoderma harzianum t-22 (rifai strain krl-ag2) under laboratory conditions. in the first two experiments, diatomaceous earth was applied at two different thicknesses (3. ... | 2007 | 17849889 |
| the influence of circulation frequency on fungal morphology: a case study considering kolmogorov microscale in constant specific energy dissipation rate cultures of trichoderma harzianum. | the energy dissipation/circulation function (edcf) is the product of the specific energy dissipation rate in the impeller swept volume (p/kd(3)) and the frequency of particle circulation (1/t(c)) through that volume. a direct relationship between mycelial fragmentation and edcf has been reported. however, and although hyphal fragmentation is assumed to occur by hyphae-eddy interaction, kolmogorov microscale (lambda) has not been shown to determine, at least directly, fungal morphology. in this w ... | 2007 | 17586080 |
| isolation and characterization of a beta-tubulin gene from trichoderma harzianum. | | 2007 | 17551827 |
| mycoparasitism studies of trichoderma harzianum strains against rhizoctonia solani: evaluation of coiling and hydrolytic enzyme production. | the genus trichoderma is a potential biocontrol agent against several phytopathogenic fungi. one parameter for its successful use is an efficient coiling process followed by a substantial production of hydrolytic enzymes. the interaction between fifteen isolates of trichoderma harzianum and the soil-borne plant pathogen, rhizoctonia solani, was studied by light microscopy and transmission electron microscopy (tem). macroscopic observations of fungal growth in dual cultures revealed that growth i ... | 2007 | 17534583 |
| characterization of genes encoding novel peptidases in the biocontrol fungus trichoderma harzianum cect 2413 using the trichoest functional genomics approach. | proteolytic enzymes (ec 3.4) secreted by trichoderma strains are receiving increasing attention because of their potential implication in the trichoderma biocontrol abilities. we have used an expressed sequence tag (est) approach to identify genes encoding extracellular peptidases in t. harzianum cect 2413 grown under several biocontrol-related conditions. based on blastx results and gene ontology annotation, a total of 61 (among 3478) unique sequences (unisequences) were predicted to encode enz ... | 2007 | 17415567 |
| removal and recovery of uranium from aqueous solutions by trichoderma harzianum. | removal and recovery of uranium from dilute aqueous solutions by indigenously isolated viable and non-viable fungus (trichoderma harzianum) and algae (rd256, rd257) was studied by performing biosorption-desorption tests. fungal strain was found comparatively better candidate for uranium biosorption than algae. the process was highly ph dependent. at optimized experimental parameters, the maximum uranium biosorption capacity of t. harzianum was 612 mg u g(-1) whereas maximum values of uranium bio ... | 2007 | 17291559 |
| hybrid mitochondrial plasmids from senescence suppressor isolates of neurospora intermedia. | we analyzed several natural suppressor isolates of the pkalilo-based fungal senescence syndrome of neurospora intermedia. the pkalilo plasmid did not increase in titer in these isolates. nor did it show integration "de novo." in at least two of the senescence suppressor isolates, pkalilo had formed stable recombinants with other mitochondrial elements. pkalilo/mtdna recombination junctions were complete and appeared to have been formed via a nonhomologous recombination mechanism. further analysi ... | 2007 | 17151255 |
| fungal biosynthesis of endochitinase and chitobiase in solid state fermentation and their application for the production of n-acetyl-d-glucosamine from colloidal chitin. | the present study was directed to the production of n-acetyl-d-glucosamine using endochitinase and chitobiase from fungal cultures in solid culturing. fifteen fungal strains were evaluated for endochitinase and chitobiase production under solid-state fermentation using agro-industrial residues, of which penicillium aculeatum nrrl 2129 showed maximum endochitinase activity whereas trichoderma harzianum tubf 927 showed maximum chitobiase activity. eleven substrates, alone and in combination with c ... | 2007 | 17092709 |
| efficient isolation of anthraquinone-derivatives from trichoderma harzianum ets 323. | anthraquinone-derivatives, chrysophanol and pachybasin, were purified by a silica column chromatography with two different solvent systems from trichoderma harzianum ets 323. the fungus was incubated in sugarcane bagasse solid medium at room temperature without rotation. structure of chrysophanol was solved by x-ray diffraction and pachybasin by nmr spectra. about 233+/-13 mg of pure chrysophanol and 773+/-40 mg of pure pachybasin were recovered per kg of solid cultural medium, with yields 1.7+/ ... | 2007 | 17067682 |
| exploitation of trichoderma harzianum mycelial waste for the removal of rhodamine 6g from aqueous solution. | the harvested mycelial waste of trichoderma harzianum was used as an adsorbent for the removal of rhodamine 6g and was studied in batch mode. the effects of agitation time and initial dye concentration, adsorbent dosage and ph were examined. the study revealed that the amount of dye adsorbed (mgg(-1)) increased with increase in agitation time and reached equilibrium after 120 min, for dye concentrations of 10-50 mg l(-1). the adsorbent dosage of 1.0 g/50 ml and ph of 8.0 were found to be optimum ... | 2007 | 17045731 |
| in vitro activity and synergism of amphotericin b, azoles and cationic antimicrobials against the emerging pathogen trichoderma spp. | the uncommon fungal pathogen trichoderma shows increasing medical importance particularly in immunocompromised patients. despite systemic antifungal therapy, prognosis of trichoderma infection is poor regardless of the type of infection and the therapy used. the aim of the present study was to evaluate the in vitro activity and synergism of double antifungal combinations including amphotericin b, voriconazole, fluconazole, chlorhexidine digluconate and akacid plus against 15 isolates of trichode ... | 2006 | 16987867 |
| the chemistry of the bio-control agent, trichoderma harzianum. | the role of 6-n-pentyl-2h-pyran-2-one and other metabolites of the fungus trichoderma harzianum, in its application as a bio-control agent, is discussed. | 2005 | 16961094 |
| generation, annotation and analysis of ests from trichoderma harzianum cect 2413. | the filamentous fungus trichoderma harzianum is used as biological control agent of several plant-pathogenic fungi. in order to study the genome of this fungus, a functional genomics project called "trichoest" was developed to give insights into genes involved in biological control activities using an approach based on the generation of expressed sequence tags (ests). | 2006 | 16872539 |
| detection of peptaibols and partial cloning of a putative peptaibol synthetase gene from t. harzianum cect 2413. | the characterization of 11- and 18-residue peptaibols (peptides synthesized by peptide synthetases) at trichoderma harzianum cect 2413 (a filamentous fungus) was performed. using a heterologous probe from tex1, the only peptaibol synthetase cloned and characterized so far in trichoderma species, was cloned; a region that comprised 11676 bp of a second peptide synthetase gene detected in these strain (called salps2) and sequenced. the deduced sequence of salps2 (3891 amino acids) contained three ... | 2006 | 16821720 |
| mechanism of action of the endo-(1-->3)-alpha-glucanase mutap from the mycoparasitic fungus trichoderma harzianum. | (1-->3)-alpha-glucanases catalyze the hydrolysis of fungal cell wall (1-->3)-alpha-glucan, and function during cell division of yeasts containing this cell wall component or act in mycoparasitic processes. here, we characterize the mechanism of action of the (1-->3)-alpha-glucanase mutap from the mycoparasitic fungus trichoderma harzianum. we observed that mutap releases predominantly beta-glucose upon hydrolysis of crystalline (1-->3)-alpha-glucan, indicating inversion of the anomeric configura ... | 2006 | 16780840 |
| enhancement of mutanase production in trichoderma harzianumby mutagenesis. | conidia of trichoderma harzianum f-340, an active producer of fungal mutanase, were mutagenized with physical and chemical mutagens used separately or in combination. after mutagenesis, the drop in conidia viability ranged from 0.004% to 71%. among the applied mutagens, nitrosoguanidine gave the highest frequency of cultures with enhanced mutanase activity (98%). in total, 400 clones were isolated, and preliminarily evaluated for mutanase activity in flask microcultures. eight most productive mu ... | 2006 | 16646531 |
| effect of substrates on growth and shelf life of trichoderma harzianum and its use in biocontrol of diseases. | a study on the effect of different agrowastes on the population density and shelf life of trichoderma harzianum indicated that all the substrates showed effective propagation of t. harzianum; however, the population count after 30 days was maximum in used tea leaves (8 x 10(8) cfu/g) and shelf life was found to be maximum (2.9 x 10(5) cfu/g after 210 days) in wheat bran-sawdust. the application of these formulations on chickpea and groundnut plants significantly reduced the percent mortality due ... | 2007 | 16495048 |
| cloning and characterization of the erg1 gene of trichoderma harzianum: effect of the erg1 silencing on ergosterol biosynthesis and resistance to terbinafine. | trichoderma species are commonly used as biocontrol agents of different plant-pathogenic fungi. terpene compounds are involved in the biocontrol process due to their antifungal properties (e.g., ergokonins and viridins) but additionally their structural function in the cell membranes (ergosterol) is essential. we report here the characterization of the t. harzianum erg1 gene, encoding a squalene epoxidase, a key enzyme in the biosynthesis of triterpene derivatives such as ergosterol. in t. harzi ... | 2006 | 16466954 |
| analysis of the beta-1,3-glucanolytic system of the biocontrol agent trichoderma harzianum. | the biocontrol agent trichoderma harzianum imi206040 secretes beta-1,3-glucanases in the presence of different glucose polymers and fungal cell walls. the level of beta-1,3-glucanase activity secreted was found to be proportional to the amount of glucan present in the inducer. the fungus produces at least seven extracellular beta-1,3-glucanases upon induction with laminarin, a soluble beta-1,3-glucan. the molecular weights of five of these enzymes fall in the range from 60,000 to 80,000, and the ... | 1998 | 16349547 |
| biological control of sclerotinia sclerotiorum attacking soybean plants. degradation of the cell walls of this pathogen by trichoderma harzianum (bafc 742). biological control of sclerotinia sclerotiorum by trichoderma harzianum. | 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 treatme ... | 1998 | 16284851 |
| 6-pentyl-alpha-pyrone production by trichoderma harzianum: the influence of energy dissipation rate and its implications on fungal physiology. | the influence of the agitation conditions on biomass growth, morphology, carbon metabolism, viability, and 6-pentyl-alpha-pyrone (6pp) production by trichoderma harzianum were studied in an extractive fermentation system. batch spore-inoculated cultures developed at dissolved oxygen concentrations above 35% of air saturation were carried out in a 14 l bioreactor. the effect of energy dissipation rate over culture performance was assessed using two sets of three rushton turbines (having different ... | 2005 | 15880469 |
| identification of genes with a biocontrol function in trichoderma harzianum mycelium using the expressed sequence tag approach. | species of trichoderma are commercially applied as biological control agents against plant fungal pathogens based on different mechanisms, such as the production of antifungal metabolites, competition for space and nutrients and mycoparasitism. but the integrated biocontrol mechanism of trichoderma harzianum is not well explored at the genetic level. this study aimed to initiate the preliminary development of an expressed sequence tag (est) database for t. harzianum and thereby gain potentially ... | 2005 | 15808946 |
| [improvement of trichoderma strains for biocontrol]. | the use of the fungal genus trichoderma to control fungal plant diseases is a promising alternative to the use of chemical compounds. the aim of this work has been to obtain trichoderma strains with improved capacity as biological control agents. to do so, the hydrolytic capacity on fungal cell walls of strains of the fungus trichoderma harzianum has been increased. on one hand, transformation experiments with genes which coded for chitinases and glucanases have been carried out in t. harzianums ... | 2000 | 15762779 |
| specific pcr assays for the detection and quantification of dna from the biocontrol strain trichoderma harzianum 2413 in soil. | strain identification in situ is an important factor in the monitoring of microorganisms used in the field. in this study, we demonstrated the use of sequence-characterized amplified region (scar) markers to detect genomic dna from trichoderma harzianum 2413 from soil. two primers (scar a1/scar a1c) were tested against dna of 27 isolates of trichoderma spp. and amplified a 990-bp fragment from t. atroviride 11 and a 1.5-kb fragment from t. harzianum 2413, using an annealing temperature of 68 deg ... | 2005 | 15688256 |
| arbuscular mycorrhiza and collembola interact in affecting community composition of saprotrophic microfungi. | the functioning of the plant-mycorrhiza system depends on interactions with other organisms, including saprotrophic (st) soil fungi. the interactions between mycorrhizal and st fungi are likely affected by fungivorous soil animals, such as collembola. in a two-factorial laboratory experiment lasting for 30 weeks we assessed the effects of an arbuscular mycorrhizal fungus (glomus mosseae) and collembola (protaphorura fimata, heteromurus nitidus and folsomia candida) on the community composition o ... | 2005 | 15619097 |
| rhizoctonia solani, an elicitor of 6-pentyl-alpha-pyrone production by trichoderma harzianum in a two liquid phases, extractive fermentation system. | 6-pentyl-alpha-pyrone (6pp) production by trichoderma harzianum, in an extractive fermentation system, was elicitated by rhizoctonia solani. the extent of 6pp elicitation was related to the state of rhizoctonia and to the trichoderma inoculum type. the use of non-viable rhizoctonia solani mycelium in mycelium-inoculated trichoderma harzianum culture, yielded the maximal 6pp production (474 mg l(-1)) compared to control cultures (147 mg l(-1)) and decreased the process time from 192 to 96 h. | 2004 | 15604771 |
| regulation of n-acetyl-beta-d-glucosaminidase produced by trichoderma harzianum: evidence that camp controls its expression. | trichoderma harzianum is a filamentous fungus reported to be a producer of extracellular n-acetyl-beta-d-glucosaminidase (nagase) when grown in chitin-containing medium. an approximately 64-kda protein with nagase activity was purified by gel filtration and ion exchange chromatography. the involvement of cyclic amp (camp) in the synthesis of nagase from t. harzianum in chitin-containing medium was also investigated. molecules that increase the intracellular levels of camp, including caffeine, al ... | 2004 | 15380555 |
| differential recognition of animal type beta4-galactosylated and alpha3-fucosylated chito-oligosaccharides by two family 18 chitinases from trichoderma harzianum. | we report the purification of two glycosyl hydrolase family 18 chitinases, chit33 and chit42, from the filamentous fungus trichoderma harzianum and characterization using a panel of different soluble chitinous substrates and inhibitors. we were particularly interested in the potential of these (alpha/beta)(8)-barrel fold enzymes to recognize beta-1,4-galactosylated and alpha-1,3-fucosylated oligosaccharides, which are animal-type saccharides of medical relevance. three-dimensional structural mod ... | 2004 | 15229194 |
| observation of protoplasts from the conidia of arthrinium aureum by scanning electron microscopy. | protoplast formation from conidia of arthrinium aureum was achieved with lysing enzyme l-2265 (sigma chemical) from trichoderma harzianum. scanning electron microscopy of conidia protoplasts showed the acquired spherical shape. | 2004 | 15119853 |
| isolation and characterization of protease overproducing mutants of trichoderma harzianum. | several trichoderma strains have been reported to be effective in controlling plant diseases, and the action of fungal hydrolytic enzymes is considered as the main mechanism involved in the antagonistic process. strain trichoderma harzianum t334 is a potential biocontrol agent against plant pathogenic fungi with the ability to produce low levels of proteases constitutively. to improve its fungal antagonistic capacity, mutagenetic program was undertaken for the construction of protease overproduc ... | 2004 | 15063489 |
| quantitative characterisation of the morphology of trichoderma harzianum cultured in shake-flasks and containing tween 40. | image analysis was used to measure the effect of tween 40 on the morphology of trichoderma harzianum. the percentage of pellets was maximal (93%) with tween at 0.2 ml l(-1), whereas the maximal proportion of dispersed mycelia (40%) was with tween at 1.6 ml l(-1). the particle median diameter decreased from 2 to 0.5 mm as tween concentration was increased and was inversely correlated to the biomass dry weight. adding pre-determined aliquots of tween 40 to the culture medium can be used to define ... | 2004 | 15005150 |