The Bioscan, 1(1-4) 047-049,2006
An International Quarterly Journal of Life Sciences
web site: www.thebioscan.in 
BIOLOGICAL CONTRAOL OF PHYTOPATHOGENS USING
ANTAGONIST TRICHODERMA VIRIDE
D.S.R. RAJENDRA SINGH*, SHAIK SAYEED**, K. BRUNDA EVI*** AND B. BHADRAIAH
"Department of Botony, **Department of Microbiology, M.V.S. Govt. Degree & P.G. College Mahabubnagar
***Department of Botony, Osmania University, Hyderabad - 500 007.
Email: b_bhadraiah@rediffmail.com
KEY WORDS

Aspergillus niger
A.fumigatus
F.oxysporum
F.solani
P.varioti
M.phaseolina
Sclerrotium rolfsii
Trichoderma,viride
Biological control


Received on: 10.10.2006

Accepted on: 11.12.2006


*Corresponding
 Author
ABSTRACT

Antagonistic fungus i.e. Trichoderma viride was tested in vitro against seven phytopathogens viz., Aspergillus niger, A. fumigatus, Macrophimina phaseolina, Fusarium oxysporum, F. solani, Paecilomyces varoti and sclerotium rolfsii. Trichoderma viride exhibited the antagonistic effect against these phytopathogens. Under dual culture the hyphal growth of the phytopathogens was inhibited at the zone of contact with the hyphae of the antagonist. Microscopic examination revealed that hyphal tips of phytopathogens swelled and become curved. The advancing hyphae of T. viride covered the entire petriplates after 6-7 days of incubation. The phytopathogens could not be reisolated from any part of the overgrown plates.Two type of mechanism of action is seen i.e. mycoparasitism and antibiosis. Trichoderma viride showed strong mycoparasitism against A. niger A. fumigatus and F. oxysporum, whereas medium intensity of mycoparasitism was shown against P. varioti, F. soloni and M.phaseolina. Trichoderma viride also showed antibiosis against S.rolfsii. Among the seven phytopathogens tested A. niger, A.fumigatus and F.oxysporum were found to be more sensitive to R. viride and were completely inhibited followed by P.varioti, F.solani, M.phaseolina and S.rolfsii. Further use of this antagonist seems to be environmentally safer alternative to the use of fungicides for various diseases.