Morphological and Molecular Identification of Trichoderma Isolates on North American Mushroom Farms

Abstract

Green mold disease (causal agent, Trichoderma) has resulted in severe crop losses on mushroom farms worldwide in recent years. We analyzed 160 isolates of Trichoderma from mushroom farms for morphological, cultural, and molecular characteristics and classified these isolates into phenotypic groups. The most common group comprised approximately 40% of the isolates and was identified as a strain of Trichoderma harzianum. This group was consistently recovered from farms with severe green mold disease but not from farms with little or no problem. In addition, the strain identified as the major cause of green mold disease in Ireland and the United Kingdom grouped with these North American isolates in having very similar randomly amplified polymorphic DNA patterns.

A new Hypocrea strain producing harzianum A cytotoxic to tumour cell lines

“…This study reports the production of cytotoxic harzianum A from a new Hypocrea strain. In spite of serious outbreaks of green mould caused by Hypocrea (Seaby 1987;Castle et al 1998), a survey of Hypocrea distribution, the natural occurrence of Hypocrea-derived mycotoxins and associated toxicities when isolated from contaminated agricultural products have not yet been undertaken. However, it seems quite possible for Hypocrea or Trichoderma and related species to exploit various natural and commercial niches such as mushroom production facilities, woodlands, varying crops, soils, producing trichothecene derivatives and mediating green mould disease.…”

“…Trichoderma and Gliocladium are known as anamorphs of Hypocrea and characterized by their ability to produce a wide range of secondary metabolites or enzymes with diverse biological actions (Papavizas 1985;Hermosa et al 2000). Especially, serious outbreaks of green mould caused by Hypocrea have occurred world widely on commercial mushrooms (Seaby 1987;Castle et al 1998). Green mould disease is characterized by an aggressive mycelium causing a soft decay and a rapid infestation of economically important crops including mushrooms (Castle et al 1998;Dodd et al 2002).…”

“…Especially, serious outbreaks of green mould caused by Hypocrea have occurred world widely on commercial mushrooms (Seaby 1987;Castle et al 1998). Green mould disease is characterized by an aggressive mycelium causing a soft decay and a rapid infestation of economically important crops including mushrooms (Castle et al 1998;Dodd et al 2002). Recently, a number of species of Hypocrea have been re-evaluated or newly found to be teleomorphs of Trichoderma (Dodd et al 2002(Dodd et al , 2003.…”

Study of the siderophore‐producing Trichoderma asperellum Q1 on cucumber growth promotion under salt stress

“…For molecular identification, five-day-old mycelium was obtained from the potato dextrose broth, frozen in liquid nitrogen and ground to a fine powder. Genomic DNA of strain Q1 was extracted using the method described by Castle et al [13]. The ITS 1, the 5.8s rRNA gene and ITS 2 region was amplified using the primer pair ITS1 primer (5 0 -TCCGTAGGTGAACCTGCG-3 0 ) and ITS4 (5 0 -TCCTCCGCTTATTGATATGC-3 0 ) [14].…”

Trichoderma harzianumelicits induced resistance in sunflower challenged byRhizoctonia solani

“…One hundred and nine isolates of Trichoderma were isolated from different agricultural fields and forest soils of Uttar Pradesh, India, using the modified Trichoderma selective medium Singh et al (2007). The colonies were determined to be Trichoderma species (Castle et al 1998). The isolates of Trichoderma were belonging to different species viz., T. harzianum, T. viride, T. koningii and T. pseudokoningii.…”