Evaluation of efficacy of Neem oil, castor oil, carbendazim, Trichoderma harzianum, Trichoderma viride and Pseudomonas fluorescens against Alternaria carthami

Abstract

The efficacy of two botanicals viz ., Neem oil and castor oil, one fungicide i.e ., carbendazim and three bioagents viz ., Trichoderma harzianum, Trichoderma viride, Pseudomonas fluorescens were tested in vitro and in vivo against Alternaria carthami inciting leaf spot safflower leaf spot/blight. In vitro efficacy of botanicals and fungicide was evaluated by poison food technique against Alternaria carthami. In vitro efficacy of bioagents was evaluated by dual culture technique against Alternaria carthami. In in vitro evaluation of fungicide and botanicals carbendazim found to be most effective and showed maximum inhibition of mycelial growth (43.33%) followed by Neem oil (30.53%). Among the bioagents maximum inhibition of radial growth of the test pathogen was noticed in P. fluorescens (87.36%) which was found on par with T. virde (86.22%). Mycelial growth of test pathogen was inhibited to an extent of 81.08 per cent T. harzianum . In in-vivo evaluation, combined seed treatment with of P. fluorescens (10 g kg-1 seed) + carbendazim (2 g kg -1 seed)+ Neem oil (10 ml kg -1 seed) was effective in controlling Alternaria leaf spot/blight.