Re: Specific Exemption Request for Use of Dimethomorph (Acrobat 50WP) to control Phytophthora blight (Phytophthora capsici) on curcurbit crops in 2002
The New York State Department of Environmental Conservation, as the State lead agency for pesticide matters, hereby requests approval of the referenced application (see enclosure) under Section 18 of the Federal Insecticide, Fungicide and Rodenticide Act, as amended. The enclosed application includes the information required in 40 CFR, Part 166, Subpart B (166.20). Also, enclosed is the use report from the 2001 Section 18 use (see Appendix 6).
This is the second year that we are requesting dimethomorph (Acrobat 50W) for emergency use to control Phytophthora Blight (Phytophthora capsici) on curcurbit crops in New York State. Phytophthora blight has been causing substantial losses in curcurbits in New York since the early 1990's. It was cited as the most important disease by some growers at the Curcurbit Crop Workshop held in March, 2001. It was first observed on Long Island and in the Capital District, then in western New York. Now it has become established in central New York, making it possible to spread to farms throughout the State.
Fosetyl-Al (Aliette) is the only fungicide currently registered for use on curcurbits to control this disease. Adequate disease control has yet to be achieved in efficacy tests conducted at Cornell University or other public institutions in the U.S. (Appendix 2). Other methods of control include a variety of cultural practices, but this is also not adequate for disease control (Appendix 3).
Recent studies conducted in Wisconsin have shown that dimethomorph, formulated as Acrobat MZ or Acrobat 50WP, provides a level of control of fruit rot greater than 60% in cucumbers (Appendix 4). Also, a 1999 study conducted in New York showed that the use of dimethomorph, combined with mancozeb or copper hydroxide, on summer squash resulted in 82% to 90% fewer fruit with symptoms of the disease (Appendix 4, Item 10).
A maximum of five foliar applications of Acrobat 50WP Fungicide per season is requested. The first application is to be made beginning when plants are four- to six-inches high or prior to the onset of disease and continued on five- to ten-day intervals. The recommended rate is 6.4 fl. oz product of Acrobat 50WP Fungicide/acre (3.2 oz ai/A). It is expected that 3600 acres will be treated. This represents 25% of the total acreage planted to curcurbit crops. Therefore, the total anticipated use of Acrobat 50WP is 7200 lb. The anticipated use season for dimethomorph in New York State is from July 1 through September.BASF Corporation, the manufacturer of Acrobat 50WP Fungicide, fully supports our efforts to obtain an emergency exemption for the use of Acrobat on curcurbits in New York State (see Appendix 1 of enclosure). Acrobat is currently registered for use on potatoes and tomatoes and is being developed for use in curcurbits as well as other crops. BASF anticipates that IR-4 will be submitting a tolerance petition for residues of dimethomorph in or on curcurbits sometime in 2002.
Please contact Robin Hackett, of our Pesticide Product Registration Section, at (518) 402-8768, if you require further assistance on this request.