Evaluation of antagonistic Pseudomonas against root lesion nematode of tea

The tea root lesion nematode, Pratylenchus loosi, has been shown internationally to be a serious nematode pest causing yield losses in tea plantations. It is one of the most important crop loss agents in Iran, which affect quantity and quality of tea leaves. Biological control agents represent an innovative alternative to agrochemicals and have potentials for control of plant parasitic nematodes. To evaluate these potentiality more than forty bacterial strains were collected from rhizosphere of tea plants and screened for their antagonistic activities towards adult and juvenile Pratylenchus loosi for population density reduction under in vitro condition. Eight selected isolates with nematicidal activity were characterized and identified. All belonged to the genus Pseudomonas. Seven strains were identified as Pseudomonas fluorescens and one as P. aeruginosa. Death percentage of juveniles ranged from 63.10% to 95.24% for P. fluorescens (Rh-36) and P. fluorescens (Rh-19), respectively.