Efficacy of bioagents and antibiotics against Xanthomonas axonopodis pv. Punicae causing oily spot disease in pomegranate

All the five species of antagonist Trichoderma and seven antibiotics evaluated in vitro were found effective against Xanthomonas axonopodis pv. punicae and recorded significant inhibition of the test bacterium over untreated control. However, T. hamatum was found most effective with significantly highest growth inhibition (22.00%) of the test bacterium. This was followed by T. harzianum and T. koningii with 15.00 and 11.00 per cent growth inhibition, respectively. The bioagents T. lignorum and T. viride were found ineffective against the test bacterium. Of the antibiotics evaluated, Cefoperozone recorded significantly highest growth inhibition (21.07%) of the test bacterium. The second and third best antibiotics found were Ceftriaxone (17.70% inhibition) and Cefaclor and Chloramphenicol (each 15.50% inhibition) both of which were on par. Rest of the antibiotics evaluated recorded growth inhibition in the range of 11.47 to 14.40 per cent.