Pest Management Science (2007) 63, 511-515

Xiaojun Yang, Lijun Yang, Shaonan Wang, Dazhao Yu and Hanwen Ni (2007)
Synergistic interaction of physcion and chrysophanol on plant powdery mildew
Pest Management Science 63 (5), 511-515
Abstract: The extract of the plant Rheum officinale Baill, mainly containing the anthraquinones physcion and chrysophanol, is highly active against plant powdery mildew. Experiments were conducted in the laboratory and greenhouse to determine the interaction of the two compounds on cucumber powdery mildew [Sphaerotheca fuliginea (Schlecht.) Poll] and on wheat powdery mildew [Blumeria graminis (DC.) Speer f. sp. tritici Marchal]. Physcion was much more bioactive than chrysophanol against these powdery mildews. There was a significant synergistic interaction between the two compounds on the diseases when the ratios of physcion to chrysophanol ranged from 1:9 to 5:5. The synergistic degree increased with increase in the chrysophanol proportion in the combination. The findings indicate that, in order to ensure constant efficacy of the extract on the disease, both the contents and the proportion of the main active ingredients physcion and chrysophanol have to be determined.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Han-Wen Ni

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.
	Blumeria graminis	Wheat (Triticum)
	Podosphaera fuliginea
	Podosphaera xanthii	Cucumber (Cucumis sativus)