Effect of biotic and abiotic agents in controlling cucumber leaf spot caused by Alternaria Cucumerina under protected cultivation [electronic resource].

Includes references.

Alternaria cucumerina was isolated from blighted or spotted cucumber leaves. Pathogenicity test revealed that A. cucumerina was pathogenic to cotyledons and true leaves of cucumber plants. Matrix cv. gave the lowest infection with A. cucumerina, while Beta alpha recorded the highest infection. On the otherhand, A. cucumerina isolated from cucumber plants had ablility to infect other cucubit plants; i.e. melon; watermelon; pumpkins, Smooth Loofah and squash. Both Bacillus spp. and Trichoderma spp. inhibited the growth of A. cucumerina either in vitro or in vivo. Trichoderma sp., T. harzianum, T. viride and different Bacillus spp. (isolated from cucumber leaf surface) and their culture filtrates significantly inhibited the radial growth of A. cucumerina on PDA medium. Various concentrations of some plant oils and plant extracts reduced the radial growth and spore germination of A. cucumerina, especially clove oil. Also, Dithane M-45 was effective in reducing the radial growth of A. cucumerina. Bacillus spp. (isolate 4), T. harzianum, clove oil and Dithane M-45 were the most effective treatments in controlling cucumber leaf spot.

Summary in Arabic.

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