Trichoderma spp. - The Cause of Green Mold on Polish Mushroom Farms

Abstract

Trichodermaspp. - The Cause of Green Mold on Polish Mushroom FarmsThe first reports concerning green mold on Polish mushroom farms are from 2002. In Europe and the United StatesTrichoderma harzianumwas initially described as a causative agent of the disease. However, soon two biotypes ofTrichoderma, Th2 in Europe and Th4 in America, were recognised as responsible for commercial losses and were designated as a new species namedT. aggressivum.Until now it has not been clear which species ofTrichodermaand which form of the species was a causative agent of the disease outbreak in Poland and what was the main source of infection. Therefore, studies were conducted on the composition of theTrichodermaspecies in Polish mushroom farms and in compost samples. The isolates were identified by phenotypic and microscopic studies. The classification of the strains recognised asT. aggressivumwas then confirmed by PCR methods. The aggressiveness ofTrichodermaspp., especiallyT. aggressivum, was estimated inin vitrostudies. The most frequently isolatedTrichodermaspp. were:T. harzianum, T. aggressivum, T. atrovirideandT. longibrachiatum.Using the technique of PCR, multiplex PCR and PCR-RAPD it was determined that 24 isolates from Polish mushroom farms belonged toT. aggressivumf.europeanum(Th2). However, a large variation between isolates indicated the possibility that Polish biotypes ofT. aggressivumwere different from those, which were found in western Europe. All isolates ofT. aggressivumwere highly pathogenic towardsAgaricus bisporus.

Impact of Infections with two Trichoderma Aggressivum F. Europaeum Isolates on the Yielding of Some Wild Strains of Agaricus Bisporus (Lange) Imbach

“…Williams et al (2003) indicated that both above-mentioned biotypes were more aggressive in comparison with other isolates of T. harzianum. The first reports about the appearance of green mould in mushroom cultivations in Poland date back to 2002 (Szczech et al 2008). The authors of this study showed that the most frequently isolated species of the Trichoderma genus identified in mushroom producing farms included: T. harzianum, T. atroviride, T. aggressivum and T. longibrachiatum.…”

Fungicide sensitivity ofTrichodermaspp. fromAgaricus bisporusfarms in Serbia

“…[3,[5][6][7][8][9][10] During the past decade, the pathogen has dispersed into Central and South East Europe, Central America and Australia. [2,[11][12][13][14][15] Green mould caused by Trichoderma spp. is characterized by white mycelia of fastgrowing colonies on casing or substrate that change color to green after profuse sporulation.…”

Trichodermaspecies onAgaricus bisporusfarms in Serbia and their biocontrol

“…In the early 1990s, green mould appeared in mushroom crops in North America, the USA and Canada, also causing enormous damage to mushroom production (Rinker, ; Romaine et al ., ). During the past decade, green mould disease of A. bisporus spread to Hungary (Hatvani et al ., ), Poland (Szczech et al ., ), Mexico (Romero‐Arenas et al ., ), Australia (Clift & Shamshad, ) and Croatia (Hatvani et al ., ). Trichoderma mycoparasitic species from the British Isles and North America were initially classified as Trichoderma harzianum Rifai (Samuels et al ., ).…”