Trichodermaspecies onAgaricus bisporusfarms in Serbia and their biocontrol

Abstract TwentyTrichodermaisolates were collected on 13 SerbianAgaricus bisporusfarms and one in Bosnia and Herzegovina during 2006–2010. Twelve isolates were classified into five species by standard mycological studies andITS1/ITS4sequence analyses, namelyTrichoderma atroviride,Trichoderma koningii,Trichoderma virens,Trichoderma aggressivumf.europaeumandTrichoderma harzianum. Eight isolates were not identified to the species level but were shown to be related toT. harzianum. The isolates ofT. harzianumexhibited the highest virulence to the harvestedA. bisporuspilei andT. virensandT. aggressivumf. europaeumthe lowest. Antifungal activity of two biofungicides based onBacillus subtilisand tea tree oil and the fungicide prochloraz manganese were testedin vitroto allTrichodermaisolates. Prochloraz manganese andB. subtiliswere highly toxic to all testedTrichodermaisolates, theirED50values were below 0.3 and 1.3 mg L−1, respectively. Tea tree oil did not exhibit a significant antifungal activity (ED50 = 11.9–370.8 mg L−1). The effectiveness of biofungicides was evaluated againstT. harzianumin a mushroom growing room, and they were applied alone or in combination with the fungicide at a respective proportion of 20:80%. Prochloraz manganese showed higher effectiveness than both tested biofungicides or their respective mixtures. The biofungicide based onB. subtilisdemonstrated greater effectiveness in preventing disease symptoms than tea tree oil.B. subtiliscombined with the fungicide revealed less antagonism in effectiveness against pathogen than tea tree oil.