Abstract

IN VITRO ANTAGONISM OF INDIGENOUS TRICHODERMA ISOLATES AGAINST PHYTOPATHOGEN CAUSING SHEATH ROT DISEASE IN PADDY

*Kalaiselvi. Selvaraj and Panneerselvam Annamalai

Abstract

The basic aim of the work was to assess the indigenous potential of bio-agents and their antagonistic potential against phytopathogen Sarocladium oryzae causing sheath rot disease in paddy. In this research work seven isolates of Trichoderma species such as T. harzianum, T. glaucum, T. viride APT01, T. viride APT09, T. album, Trichoderma sp.KP2 and T. hamatum. Efficacy of these bioantagonists were investigated in in vitro conditions by employing dual culture technique and liquid culture filtrate assay. The outcome of in vitro dual culture testing revealed that among the different isolates of Trichoderma harzianum and T.viridae were found to be more efficient amongst all, as they showed better antagonism against the tested phytopathogen. The maximum percentage inhibition of S. oryzae was observed with Trichoderma harzianum (79%) followed by T. viride AP01and T. viride AP09 (78%). Rest isolates were moderate in activity. Metabolites extracted from liquid culture filtrates also depicted almost the same trend of superiority as mentioned in dual culture i.e. the same isolates further proved its better potentiality when compared with rest, T.harzianum with superior bio-antagonistic potential.

Keywords: Trichoderma spp. S.oryzae, antagonistic activity, phytopathogen, Sheath rot, Paddy.