In vitro and in vivo evaluation of antagonistic potentiality of Trichoderma spp. against Fusarium moniliforme Sheld. causing stalk rot of maize

The aim of the present study was to evaluate the efficacy of local isolates of Trichoderma collected from rhizosphere of maize plants raised in stalk rot infested fileds under in vitro as well as in vivo conditions. Majority of the isolates were identified as T. viride and T. harzianum whereas only one isolate was identified as T. aureoviride. In vitro evaluation of Trichoderma spp. against Fusarium moniliforme was done by using dual culture technique. All of the Trichoderma isolates had a significant inhibitory effect on the growth of the pathogen over control. Out of the three, T. harzianum showed maximum antagonism against F. moniliforme, followed by T. viride and T. aureoviride. T. harzianum alone as well as combination of T.harzianum with T.viride were further evaluated as talc based formulation under pot house conditions through seed @ 10, 15 and 20 g/kg seed with incubation at 25±2p C for 24 hours; soil treatment@ 10, 15 and 20 g/kg soil and FYM supplemented with T. harzianum (25:1 ratio) @ 25, 50 and 100 g/kg soil incubated for 72 hours at 25±2p C. All the experiments were conducted in F. moniliforme sick soils. Maximum seed germination was recorded in T. harzianum treated seed @ 20g/kg closely followed by FYM (94.2%) supplemented with T. harzianum (25:1) @ 100g/kg soil as compared to control (60.2%). Root shoot ratio was significantly higher in FYM (18.5:50.38) supplemented with T. harzianum (25:1) @ 100g/kg soil followed by soil treatment (18:48.25) @ 20g/kg soil. Similar trend was observed in case of fresh and dry weight of samples. Per cent decrease in stalk rot severity was 79.04 per cent and 72.4 per cent in FYM supplemented with T. harzianum (25:1) @ 100g/kg soil and soil treatment @20g/kg soil respectively. These treatments are being evaluated under field conditions as well.