TITLE:
Growth and Antagonism of Trichoderma spp. and Conifer Pathogen Heterobasidion annosum s.l. in Vitro at Different Temperatures
AUTHORS:
Vizma Nikolajeva, Zaiga Petrina, Livija Vulfa, Laura Alksne, Daina Eze, Lelde Grantina, Talis Gaitnieks, Anita Lielpetere
KEYWORDS:
Trichoderma; Heterobasidion; Antagonism; Growth Rate; Temperature
JOURNAL NAME:
Advances in Microbiology,
Vol.2 No.3,
September
25,
2012
ABSTRACT: Variations in the radial growth rate of 24 isolates belonging to ten species of Trichoderma, three isolates of conifer pathogen Heterobasidion annosum s.s. and four isolates of H. parviporum were evaluated by incubation on a solid malt extract medium at a temperature of 4℃, 15℃ and 21℃. Trichoderma antagonism against Heterobasidion was investigated in dual culture in vitro. The slowest rate of growth was referable to all seven strains of Heterobasidion spp. All Heterobasidion spp. strains were overgrown by 63% of Trichoderma spp. strains after two weeks at 21℃ and by 33% of strains at 15℃. 21% of Trichoderma strains did not grow and only four strains belonging to T. koningii, T. viride and T. viridescens demonstrated the ability to completely overgrow Heterobasidion spp. after two weeks incubation at 4℃. According to the antagonistic efficiency, Trichoderma strains were divided into five groups with an Euclidean distance of 25. The groups contained isolates from different species. It was suggested that selected psychrotrophic fast growing T. viride, T. koningii and T. viridescens strains could be examined in different substrate conditions as suitable antagonist agents for the control of H. annosum and H. parviporum.