Pesticide Science (1999) 55, 681-686

Hiroto Tamura, Akira Mizutani, Hideo Yukioka, Nobuo Miki, Katsuaki Ohba and Michio Masuko (1999)
Effect of the methoxyiminoacetamide fungicide, SSF129, on respiratory activity in Botrytis cinerea
Pesticide Science 55 (7), 681-686
Abstract: (E)-2-Methoxyimino-N-methyl-2-[2-(2,5-dimethylphenoxymethyl)phenyl]acetamide (SSF129) has been developed as a broad-spectrum systemic fungicide for control of cereal and fruit diseases. This compound inhibited NADH-oxidation by submitochondrial particles from mycelial cells of Botrytis cinerea, with an EC₅₀ value of 14.5 nM, due to blockage of electron transport through the cytochrome bc1 complex in the mitochondrial respiratory chain. However, SSF129 did not suppress, but rather increased, oxygen consumption by mycelial cells of the fungus. This was because mycelial cells contain an alternative oxidase protein and the cells have the ability to rapidly switch electron flux from the main cytochrome pathway to the alternative pathway on blockage of the former by SSF129. The alternative pathway of the mycelia seems not to be operative when the cytochrome pathway is functional. Naturally occurring flavonoids inhibited the alternative oxidase of the mycelial cells in a dose-dependent manner, with EC₅₀ values of 68.4 µM for flavone and 63.7 µM for flavanone. These observations suggested that plant components play an important role in control of gray mould by SSF129.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)

Research topic(s) for pests/diseases/weeds:
control - general

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Botrytis cinerea