Biological properties of the novel fungicide cyazofamid against Phytophthora infestans on tomato and Pseudoperonospora cubensis on cucumber.
Cyazofamid (ISO proposed common name), 4-chloro-2-cyano-N,N-dimethyl-5-p-tolylimidazole-1-sulfonamide is a novel fungicide exhibiting specific activity against diseases caused by Oomycetes. In tests, cyazofamid at 0.4-1.6 mg litre-1 exhibited excellent preventative activity against Phytophthora infestans on tomato and Pseudoperonospora cubensis on cucumber. Minimum inhibitory concentrations of cyazofamid against both diseases were over 63 times lower than those of mancozeb and at least 16 times lower than those of metalaxyl. Cyazofamid at 1.6-25 mg litre-1 exhibited not only preventative activity, but also stable residual activity and rainfastness. Cyazofamid at 6.3 mg litre-1 reduced zoosporangia formation of P infestans and P cubensis on host plants by 100 and 94% respectively. Cyazofamid also exhibited translaminar and curative activity. Cyazofamid has a new mode of action for fungicides and exhibits no cross-resistance with other currently registered and commonly used fungicides. These properties lead to a high level control by cyazofamid in field.
Mitani
Shigeru
S
Central Research Institute, Ishihara Sangyo Kaisha Ltd, 2-3-1 Nishi-Shibukawa, Kusatsu, Shiga 525-0025, Japan. s-mitani@iskweb.co.jp
Araki
Satoshi
S
Yamaguchi
Tomona
T
Takii
Yasuko
Y
Ohshima
Takeshi
T
Matsuo
Norifusa
N
D000409:Alanine / Q000031:analogs & derivatives* / Q000633:toxicity; D000818:Animals; D018553:Cucumis sativus / Q000382:microbiology*; D004305:Dose-Response Relationship, Drug; D005659:Fungicides, Industrial / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity*; D007093:Imidazoles / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity*; D018551:Solanum lycopersicum / Q000382:microbiology*; D008344:Maneb / Q000633:toxicity; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009868:Oomycetes / Q000187:drug effects*; D010838:Phytophthora / Q000187:drug effects*; D013449:Sulfonamides / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity*; D015038:Zineb / Q000633:toxicity
D005659:Fungicides, Industrial; D007093:Imidazoles; D013449:Sulfonamides; D008344:Maneb; C028175:metalaxyl; D000409:Alanine; C465366:cyazofamid; C013099:mancozeb; D015038:Zineb