Department of Plant Pathology, Acharya N.G. Ranga Agricultural University, Hyderabad-500030.
* Paper presented in the National Seminar on Plant Protection towards Sustainability at the NPPTI, Hyderabad.
Antagonistic nature of different isolates of’Trichoderma and Gliocladium spp. viz., one native Trichoderma harzianum (H5), other exotic isolates of T. harzianum (HI, H2, H3, H4) T. viride (VI, V2), G. virens (G1, G2), T. koningii (K), T. pseudokoningii (TPK), T. longibrachiatum (TL) and T. hamatum (TH) were tested against the dry root rot pathogen M. phaseolina in dual culture technique. All the isolates reduced the growth of A/. Phaseolina. Maximum inhibition of pathogen growth was observed with native isolate of T. harzianum (H5) (69.28%) followed by T. viride (V2) (64.94%), G. virens (G2) (64.84%) and least with T. koningii (K) (49.06%). Microscopic observations from the zone of intermingling hyphae in dual cultures revelated the mycoparasitic nature of native isolate of T. harzianum on the growth and sclerotial formation of the pathogen. In addition inhibition zones were also observed in dual culture plates 5 days after incubation and was maximum with native isolate of T. harzianum (H5) at different concentrations (5, 10, 20 and 40%) inhibited the mycelial growth of M phaseolina in PDA (Solid medium) and reduced dry weight in potato dextrose broth (liquid medium).
