Antifungal activity of the novel fungicide cyazofamid against Phytophthorainfestans and other plant pathogenic fungi in vitro

Citation
S. Mitani et al., Antifungal activity of the novel fungicide cyazofamid against Phytophthorainfestans and other plant pathogenic fungi in vitro, PEST BIOCH, 70(2), 2001, pp. 92-99
Citations number
17
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Entomology/Pest Control","Biochemistry & Biophysics
Journal title
PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY
ISSN journal
0048-3575 → ACNP
Volume
70
Issue
2
Year of publication
2001
Pages
92 - 99
Database
ISI
SICI code
0048-3575(200106)70:2<92:AAOTNF>2.0.ZU;2-P
Abstract
Antifungal activity of the novel fungicide cyazofamid (ISO proposed common name), 4-chloro-2-cyano-N,N-dimethyl 5-p-tolylimidazole-1-sulfonamide, was investigated. Cyazofamid proved highly selective to fungi classified as Oom ycetes in mycelial growth inhibition rests. The EC50 values of cyazofamid a gainst Phytophthora infestans, Phytophthora sojae, Pythium aphanidematum Py thium paddicum, Pythium sylvaticum, and Aphanomyces cochlioides were betwee n 0.008 and 0.2 mug/ml. On the other hand, cyazofamid did not inhibit mycel ial growth of fungi classified as Ascomycetes, Basidiomycetes, or Deuteromy cetes. Cyazofamid strongly inhibited all stages in the life cycle of P. inf estans. Minimum inhibitory concentrations (over 90% inhibition) against ind irect germination of zoosporangria (zoospore release), zoospore motility, c ystospore germination, and oospore formation were 0.1-0.5, 0.005, 0.05, and 0.01 mug/ml, respectively Cyazofamid at 0.1 mug/ml exhibited complete fung icidal activity on zoospore release by P. infestans 60 min after treatment. When 20 muM ATP was applied to a zoosporangia suspension before addition o f 0.05-0.1 mug/ml cyazofamid, inhibition of zoospore release was reduced. T hese results suggest that the mode of action of cyazofamid is connected to impairment of the ATP energy generation system. (C) 2001 Academic Press.