Trichoderma harzianum

About: Trichoderma harzianum is a research topic. Over the lifetime, 4731 publications have been published within this topic receiving 96796 citations.

Generation, annotation and analysis of ESTs from Trichoderma harzianum CECT 2413

Abstract: 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). Eight different cDNA libraries from T. harzianum strain CECT 2413 were constructed. Different growth conditions involving mainly different nutrient conditions and/or stresses were used. We here present the analysis of the 8,710 ESTs generated. A total of 3,478 unique sequences were identified of which 81.4% had sequence similarity with GenBank entries, using the BLASTX algorithm. Using the Gene Ontology hierarchy, we performed the annotation of 51.1% of the unique sequences and compared its distribution among the gene libraries. Additionally, the InterProScan algorithm was used in order to further characterize the sequences. The identification of the putatively secreted proteins was also carried out. Later, based on the EST abundance, we examined the highly expressed genes and a hydrophobin was identified as the gene expressed at the highest level. We compared our collection of ESTs with the previous collections obtained from Trichoderma species and we also compared our sequence set with different complete eukaryotic genomes from several animals, plants and fungi. Accordingly, the presence of similar sequences in different kingdoms was also studied. This EST collection and its annotation provide a significant resource for basic and applied research on T. harzianum, a fungus with a high biotechnological interest.

Proteomic study of biocontrol mechanisms of Trichoderma harzianum ETS 323 in response to Rhizoctonia solani.

Abstract: 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, � -1,3-glucanase, � -1,6-glucanase, mannanase, and protease,were revealed by activity assay, in-gel activity stain, 2-DE, and LC-MS/MS analysis. Extracellular protein extracts from media that contained R. solani exhibited much higher CWDE activities than media that did not contain R. solani. Cellulase and mannanase activity, however, were insignificant. Activity stain also revealed that � -1,3-glucanase, � -1,6-glucanase, and xylanase activity occurred exclusively in media that contained R. solani. Furthermore, 35 of the 43 excised spots on the 2-DE gel were successfully analyzed by LC-MS/MS, and eight proteins were identified. They were two glycoside hydrolases, two proteases, two � -glucosidases, one endochitinase and, interestingly, one amino acid oxidase. Additionally, a possible mechanism was proposed to elucidate how the cell walls of R. solani are systematically enveloped and disintegrated.

Biological control of fusarium wilt of tomato by antagonist fungi and cyanobacteria

Abstract: Biological control of Fusarium oxysporum f. sp . lycopersici (FOL) causing wilt disease of tomato was studied in vitro as well as under pot conditions. Dual culture technique showed that Aspergillus niger, Penicillium citrinum, Penicillium sp. and Trichoderma harzianum inhibited the radial colony growth of the test pathogen. Methanol extract of Nostoc linckia and Phormidium autumnale showed moderate and minor zone of inhibition. Maximum seed germination was observed in seeds treated with N. linckia (93%), whereas, T. harzianum, P. autumnale, P. citrinum showed 80% seed germination, while A. niger treated seeds showed 50% germination. Under pot conditions, the plant heights, fresh and dry weight of plants were found to be increased significantly (p ≤ 0.05) in all treatments except in P. autumnale amended soil. Similar results were observed in chlorophyll (a+b) content of treated plants. Maximum control of wilt disease was observed with T. harzianum (44.4%) treated plants as compared to FOL inoculated plants. Whereas, effectiveness of the other antagonists were recorded in the following order: A. niger (35.6%), N. linckia (33.3%), P. citrinum (24.4%), and P. autumnale (0.9 %). Key words : Biological control, fusarium wilt, tomato, antagonist fungi, cyanobacteria

Trichoderma harzianum L1 as a potential source for lytic enzymes and elicitor of defense responses in chickpea (Cicer arietinum L.) against wilt disease caused by Fusarium oxysporum f. sp. ciceri.

Abstract: The effect of some natural lignocellulosic substances on the production of �-glucanase, chitinase, protease and xylanase from Trichoderma harzianum L1 has been studied under solid state fermentation conditions. Maximum activities of all these enzymes were observed in the fermentation medium containing the mixture of 1% rice bran, neem cake and 0.1% crab shell powder. The induction of plant defense response was investigated by inoculating the roots of chickpea cv JG62 with the biocontrol agent, T. harzianum L1. A root extract of chickpea inoculated with T. harzianum L1 showed increased activities of phenylalanine ammonia lyase and polyphenol oxidase, as well as induction of new trypsin and chymotrypsin inhibitors. The Fusarium oxysporum protease-2 was inhibited completely by root extract of chickpea inoculated with T. harzianum L1 and showed maximum resistance to rotting of roots caused by wilt disease

Trichoderma protoplast fusion: a tool for improving biocontrol agents

Abstract: Protoplasts from two auxotrophic mutants of Trichoderma harzianum Rifai (ATCC 32173), obtained from young thalli following cell wall digestion by NovoZym 234, were fused in 33% PEG suspended in 10 ...