Pesticide Use Tips
Friday, 13 February 2009 11:11
As you gear up for the growing season, be sure to carefully read pesticide labels before purchasing a new product. Some products with different trade names have the same active ingredients. Some products may have different active ingredients, but have the same mode of action (MOA). Growers will see more generic products on the market as pesticides come off patent, which can make choosing pesticides very confusing. There are now many different products containing imidacloprid, abamectin, bifenthrin, permethrin, chlorothalonil and thiophanate methyl. Growth regulators containing paclobutrazol include Bonzi, Piccolo, Paczol and Downsize. Read labels carefully since there are similarly named products that may have slightly different concentrations of active ingredient.
A good example is Banrot which contains the active ingredients thiophanate methyl & etradiazole, the same active ingredients as Cleary's 3336 (thiophanate methyl) and Truban (etradiazole). Different formulations (flowable, wettable powder, emulsifiable concentrate etc.) of products often contain different concentrations of active ingredient. Both Cleary's and Truban are available in various formulations. Over-application of a pesticide, especially emulsifiable concentrates (EC) and surfactants can cause phytotoxicity.
Continued use of products with the same mode of action can lead to pesticide resistance. To help delay pesticide resistance, rotate pesticides with different modes of action (MoA). Most pesticides have a number on the label that correlates with their mode of action group to make it easier to recognize the MoA for rotation. This can be found on the website below or in the New England Greenhouse Floriculture Guide Unless directed on the pesticide label, switch to a insecticide or miticide with a different mode of action about every 2 to 3 pest generations, or about every 2-3 weeks, depending on temperature and length of insect or mites life cycles.
Resistance also develops when fungi are repeatedly exposed to fungicides with a single site mode of action (systemic fungicides). It requires very little genetic change in fungus populations for resistance to develop. Protectant fungicides are less likely to develop resistance problems for they have multi-site modes of action (MoA). To help prevent the development of resistance, alternate applications among different MOA groups, or mix or rotate systemic/protectant fungicides.
Pesticide labels, material safety data sheets (MSDS), mode of action and related information can be found on the following websites:
Greenbook/C&P Press, Inc.
www.greenbook.net
CDMS, Inc
http://www.cdms.net/LabelsMsds/LMDefault.aspx
Kelly Registrations Systems, Inc. (pesticide registrations)
www.kellysolutions.com
IRAC Mode of Action Classification
www.irac-online.org
FRAC Codes
www.frac.info/frac/index.htm
Tina Smith, University of Massachusetts
Leanne Pundt, University of Connecticut
