2017 ASHS Annual Conference
Environmentally Friendly Management of Root-knot Disease on Melon with Bioformulated Pseudomonas chlororaphis O6
Environmentally Friendly Management of Root-knot Disease on Melon with Bioformulated Pseudomonas chlororaphis O6
Thursday, September 21, 2017
Kona Ballroom (Hilton Waikoloa Village)
Root-knot nematodes are one of the most serious pests in melon as it is cropped continuously in greenhouses. However, only limited and costly chemical methods are available for nematode control. In previous field work, a biocontrol agent, Pseudomonas chlororaphis O6, showed strong efficacy against root-knot nematode. In the summer of 2015, P. chlororaphis O6 strain, formulated with freeze-drying agents as a wettable powder form, was applied to melon fields in greenhouse at Gosung in South Korea. The nematocide, Fosthazate, was used for comparison as an authentic chemical pesticide. The melon cultivar Early Elite was transplanted into soil used for three years for melon cultivation; plants in 2014 were highly infected with root-knot nematode. Disease severity in 2015 was rated based on larval mortality, number of galls/plant and plant growth parameters. Root drenches of both the biocontrol and chemical products at transplant stage reduced nematode populations significantly (P<0.01). Reduction was greater (P<0.05) with the biocontrol agent (88 – 93 %) than with applications of Fosthazate (69 %). Drenching with the bioformulation improved (P<0.05) plant height, leaf length, leaf width, and stem diameter when compared with growth of melon treated with the chemical. Fruit yield was 20 % higher. These findings suggest that bioformulation of P. chlororaphis O6 provides a sustainable alternative to chemical use for control of root-knot nematode. Applications of the biocontrol agent can become integrated into management strategies for root-knot disease in melon.