Morphological and Molecular Characterization of Trichoderma Isolates: An Antagonist against Soil Borne Pathogens

Trichoderma has attained importance as a substitute of chemical pesticides all over the world. Hence, an attempt was intended to corroborate the positive relatedness of molecular and morphological characters with antagonistic ability. Among many isolates of Trichoderma atroviride isolated from rhizospheric soils from different parts of U. P. has brought attention due to its highly antagonistic activity. Eight isolates of Trichoderma atroviride were assessed for their mycoparasitic and molecular variability. These were isolated on PDA medium by serial dilution and identified based on phenotypic characters like colony colour, growth, shape of conidiophore, phialides and conidia. Antagonistic variability of the isolates of T. atroviride revealed significant suppression in the radial growth of Fusarium oxysporum f. sp. ciceri, F. oxysporum f. sp. lentis and F. oxysporum f. sp. udum. Maximum inhibition (60.26 %) of mycelial growth was recorded in case of TH1 isolate against Fusarium oxysporum f. sp. lentis (F. o. l. ) which was isolated from the soil sample of Bilgram (Hardoi), followed by TE8 (50 %) isolated from Bharthana (Etawah). TS5 (39.76 %) isolate from Lainbua (Sultanpur) was found to be least effective against F. o. l. Similarly, in case of Fusarium oxysporum f. sp. ciceri (F. o. c), the maximum inhibition (55.08 %) of mycelial growth was shown by the isolate TH3, which was isolated from the soil sample of Bilgram (Hardoi). The next effective isolate was TS6 (53.65 %) isolated from Kadipur (Sultanpur). Isolate TSi4 (37.69 %) of Misrikh (Sitapur) was found least effective against F. o. c. Maximum inhibition in case of Fusarium oxysporum f. sp. udum (F. o. u) was recorded with isolate TAU8 (47.91 %) from Azeetmal (Auraiya). Next effective isolate was TBa1 (47.25 %) isolated from Ballaha (Bahraich). The least effective isolates were TSi3 (41.66 %) and TKD3 (41.66 %) isolated from Misrikh (Sitapur) and Maitha (Kanpur Dehat). Molecular variability among the isolates showed 74 amplified bands out of which 65 were polymorphic and 19 were monomorphic. The size of amplified product varied from 0.1kb to 0.75kb.