Antagonistic Effects of Trichoderma Species in Biocontrol of Armillaria Root Rot Disease In Vitro Conditions

Abstract

Aim of study: Armillaria root rot is a disease of fruit trees, some herbaceous plants and forest trees. Armillaria spp. which cause this disease, are among the most destructive fungal pathogens of trees. In this study, antagonistic effects of Trichoderma species in biocontrol of Armillaria were investigated in vitro conditions Area of study: The study area was in the Düzce University, Konuralp Campus. Material and methods: Trichoderma harzianum was provided from Düzce University, Faculty of Forestry, Department of Forestry Industrial Engineering (FS19) and Trichoderma viride was provided from Düzce University, Konuralp Campus. Armillaria mellea and Desarmillaria tabescens were isolated from the infected roots of hazelnut and oak trees in Konuralp Campus and cultured in potato dextrose agar. Trichoderma species were inoculated to confront with the pathogens in cultures of Armillaria and Desarmillaria to determine antagonistic effects for 15 days. Penetration of Trichoderma hyphae in rhizomorphs and sporulation of Trichoderma species in the surface of rhizomorphs were investigated by scanning electron microscopy. Main results: The statistically significant decrease was observed for A. mellea and Desarmillaria species caused by Trichoderma. One day after Trichoderma inoculation, Trichoderma hyphae grew approximately twice as much towards the host rhizomorphs. Three days after colonization of Armillaria and Desarmillaria rhizomorphs by Trichoderma, growth of Armillaria and Desarmillaria seemed to completely stopped. Highlights: Trichoderma species have been studied as the most widely used antagonists in biological control against many plant-pathogenic fungi worldwide. To develop an effective biological method for plant protection in the future, biological control studies are highly important in oak forest under natural stand conditions.