Biomics

Downy mildew or peronosporosis is a dangerous disease of gourds caused by oomycetes of the genus Peronoplasmopara. The disease affects the leaves, on which necrotic spots form. The loss of foliage delays the process of fruit set and their normal development, which negatively affects the yield. Mature fruits of melon affected by downy mildew are slightly colored and tasteless. Under conditions of drip irrigation, used in the arid climate of the Astrakhan region, this disease actively develops and spreads, often leading to the complete death of the crop. In this paper, we studied the effect of a biological agent based on Bacillus atrophaeus, cultivated on legume and corn-molasses media, on reducing the incidence of downy mildew in melons in arid climates. In the course of field tests, the effect of laboratory samples of the agent on the development of downy mildew of the «Lada» melon variety was established: the development of the disease decreases, the number of infected plants and fruits decreases. Controlling the development of peronosporosis contributes to an increase in the yield of melons and a decrease in the content of diseased fruits in the crop. The bean-based agent had a more significant effect on reducing the development of the disease, yield, growth and shaping processes of cultivated gourds in comparison with the corn-molasses base and control. The use of a biological agent based on B. atrophaeus in the cultivation of melons in the Astrakhan region proves the effectiveness of the use of biological methods of plant protection and the prospects for their introduction into the region's agriculture.

downy mildew, peronosporosis, microorganisms of the genus Bacillus, gourds, melon (Cucumis melo), drip irrigation, biological plant protection product, bean medium, corn molasses medium, farming, agriculture

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