Grape downy mildew, control

Serres, J.M., and Carraro, G.A. 1976. DPX-3217, a new fungicide for the control of grape downy mildew, potato blight and other Peronosporales. Meded. Fac. Landbouwwet. Rijksuniv. Gent 42, 645-650. 

Three acylalanine compounds, metalaxyl (Ridomil), cyprofuram (Vini-cur) and benalaxyl (Galben), have been tested extensively for control of grape downy mildew in New York. None of these compounds are currently registered in the US. They are narrow spectrum, but highly effective compared to standard protectants such as captan, folpet or mancozeb. They have local systemic activity and possess protectant and antisporulant, as well as after-infection activity. Similar to the EBI compounds, the after-infection capabilities and their activity over extended intervals (14-21 days) make the acylalanines desirable tools for IPM programs. 

Some representative compounds from the family of 4>phenethylaminoquinolines were examined under field conditions to determine their level of control against grape downy mildew of Niagara grapes and compared to the initial lead, compound 1. As can be seen in Table V, a number of these compounds gave good-to-excellent control at levels of 100-500 ppm, much lower than the comparable activity shown by the parent compound, compound 1. 

Some of the specific conclusions reached concerning structural requirements of this series for the control of squash and grape downy mildew were as follows ... 

Benthiavalicarb (4, benthiavalicarb-isopropyl, KIF-230, Fig. 18.6) was discovered by Kumiai-Ihara and has been developed for the control of Oomycete diseases such as downy mildews Plasmopara viticola and Pseudoperonospora cuhensis) on grape vine and vegetables and late blight Phytophthora infestans) on potatoes [4, 16]. The valinamide derivative benthiavalicarb (4) shows a close structural similarity to iprovalicarb (3). 

Field Results. Three compounds from the SAR (Tables I and II) were tested under field conditions in Europe and the U.S. as broad spectrum fungicides. This series was most effective for the control of apple scab and grape downy and powdery mildew in the range of 750 to 1000 ppm. 

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