ارزیابی فعالیت آنتاگونیستی

Evaluation of antagonistic activity of trichoderma spp. Psendomonas fluorescens and Bacillus subtilis on pythium ultimum the causal agent of cucamber Damping-off

M.Taghinasab, H. Ruhani
Some samples of rhizoshperic soils were collected from cucumber fields in Hamedan, Kermanshah and kordestan provinces. This samples were used for isolation of Bacillus subtilis. Samples were cultured according to the serial dilution medium. Preliminary-bacterial and 21 trichoderma and pseudomonas flourescens isolates were screened against p.ultimum. The bacterial isolate were tested, for inhibitory activites and the trichoderma isolates were tested for inhibitory and hyper parasitic activities on p.ultimum by tow methods:
Dual culture and culture upon the colony of target fungus respectively. The results showed that isolates B.subtilis, trichoderma sp. (2), trichoderma sp (3) and pseudomonas fluorescens have more inhibitory effect toward the mycelial growth of P.ultimum and isolates T.harzianum, T.Pseudokoningi and trichoderma sp (1). On the basis of this results we can propose application of integrated isolates belonging to P.fluorescens and Trichoderma sp (2) and trichoderma sp (3) isolates for biological control cucumber damping-off. The greenhouse tests are accomplishing for using the single and integrated isolates.