The aim of the present study was to control the dry and soft rot diseases of potato tubers caused by Fusarium solani and Erwinia carotovora, respectively using some essential oils, fungicides and some antagonistic fungi, each by in vitro and in vivo studies. All of the essential oils tested (lemongrass, spearmint, peppermint, geranium, fennel, bisilicum, marjoram and carnation) and fungicides (galben mancozeb and galben copper) markedly inhibited the growth of F. solani and E. carotovora in vitro. The degree of inhibition was directly proportional with concentration of the essential oils and fungicides used. The growth was totally inhibited at the minimum inhibitory concentration (MIC) of all essential oils and fungicides tested. Trichoderma harzianum markedly inhibited the mycelial growth of F. solani in vitro, while Geotrichum candidum showed an inhibiting effect on E. carotovora. Pretreating susceptible potato tubers with the tested essential oils, fungicides at the MIC or with spores of antagonistic fungi, separately, caused complete inhibition to the dry and soft rot diseases of potato tubers caused by F. solani and E. carotovora, respectively.
Key words: Dry rot, soft rot, Fusarium solani, Erwinia carotovora, essential oils, fungicides, Trichoderma harzianum and Geotrichum candidum.
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