Trichoderma harzianum

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

Biological Control of Fusarium spp. in Cotton, Wheat and Muskmelon by Trichoderma harzianum

Abstract: A new isolate of Trichoderma harzianum (T-35) was isolated from the rhizosphere of cotton plants from a field infested with Fusarium. Under glasshouse conditions, the antagonist was applied to soil growing in a bran/peat mixture (1:1, v/v) or as a conidial suspension or used as a seed coating. When T. harzianum was tested against Fusarium oxysporum f. sp. vasinfectum, F. oxysporum f. sp. melonis or F. roseum‘Culmorum”, a significant disease reduction, was obtained in cotton, melon and wheat, respectively. Biological control of Fusarium wilt of cotton was achieved when tested at two inoculum levels of the pathogen (2 × 107 and 2 × 108 microconidia/kg soil), decreasing the Fusarium spp. soil population. The long term effect of T. harzianum on Fusarium wilt of cotton was studied using successive plantings. The antagonist persisted in soil throughout three consecutive plantings, reducing the Fusarium, wilt incidence in each growth cycle. At the first planting the largest amount of preparation was found superior, whereas at the third planting, no significant difference could be observed between the four rates of Trichoderma preparation. T. harzianum (T-35) controlled Fusarium wilt in cotton and muskmelon when applied in both naturally or artificially infested alluvial vertisol and sandy-loam soils, respectively. Soil or seed treatments with the antagonist provided a similar disease control of F. roseum‘Culmorum’ and of F. oxysporum f. sp. melonis.

Use of Trichoderma harzianum in combination or alternation with fungicides to control cucumber grey mould (Botrytis cinerea) under commercial greenhouse conditions

Abstract: A preparation of Trichoderma harzianum was sprayed on cucumber plants in greenhouses in order to control fruit and stem grey mould. Up to 90% control was achieved by the biocontrol agent (0·5–1·0 g/l) which in most experiments under commercial conditions was as effective as the dicarboximide fungicides iprodione or vinclozolin (0·5 g/l each) alone or alternated with diethofencarb + carbendazim (0·25 g/l each). However, in one experiment disease incidence in Trichoderma-treated plots did not differ significantly from the control. A mixture of T. harzianum with a dicarboximide fungicide resulted in up to 96% control of grey mould. In this case control was always significant (P=0·05) but improvement of control compared with each treatment alone was not significant (P=0·05). The alternation of sprays with the biocontrol preparation and with a dicarboximide fungicide was tested in three out of the five experiments and was found to be effective, thus enabling a reduction in the use of chemical sprays. Populations of T. harzianum were on a level of 3 × 105-8 × 105 c.f.u. per leaf and ten times lower on one fruit. They remained high after the second and third sprays. Conditions favouring the ability of T. harzianum to control grey mould were temperatures above 20°C and relative humidity between 80 and 97%.

Harzianic acid, an antifungal and plant growth promoting metabolite from Trichoderma harzianum

Abstract: A Trichoderma harzianum strain, isolated from composted hardwood bark in Western Australia, was found to produce a metabolite with antifungal and plant growth promoting activity The structure and absolute configuration of the fungal compound, harzianic acid (1), were determined by X-ray diffraction studies Harzianic acid showed antibiotic activity against Pythium irregulare, Sclerotinia sclerotiorum, and Rhizoctonia solani A plant growth promotion effect was observed at low concentrations of 1