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Fungicides and culture filtrate of native bio-agents were evaluated to test their proficiency to control gummy stem blight disease caused by Didymella bryoniae in Gherkins. Amongst the tested culture filtrate of antagonistic bioagents, Trichoderma harzianum (THRHG1 strain) at 20% concentration showed 43.1% mycelial growth inhibition which was maximum followed by Penicillium purpurogenum -1 (PPDMK1) at 5% concentration which showed 3.36% growth inhibition. Aspergillus terreus (ATKGM1) and Penicillium purpurogenum-2 (PPDMK-2) showed minimum growth inhibition. Further, Didymellq bryoniae showed highly sensitive to fungicides viz. Mancozeb 75% (Indofil) and Tebuconazole 50% (Nativo) with 100% growth inhibition at very low concentration and found to be least sensitive to other fungicides viz. Allite, Sectin and Kavach. In green house experiments A. terreus (ATKGM1) and P. purpurogenum-2 (PPDMK-2) significantly reduced the disease incidence by 43.8% and 44.6% respectively, when compare to negative control which showed 96.5% disease incidence. Furthermore, both isolates were proved to be good growth promoter compared to overall control which was evident by increase in shoot length 54.2±7.9 and 62.0±8.3, number leaf 13.5±1.0 and 11.1±1.8 respectively. Interestingly, T. harzianum, which was highly effective in vitro, proved to be less effective in green house condition. These results revealed A. terreus and P. purpurogenium can become a good biocontrol agent in managing gummy stem blight disease caused by D. bryoniae in Gherkins.

Key words: Bioagents, Didymella bryoniae, Fungicides, Gummy stem blight, Poisoned food technique.