November-December 2005

Pesticide Potpourri

  • wpdoc8.gifA new pesticide analysis scheme was published recently that is capable of analyzing 112 halogenated (but no phosphorous) pesticides simultaneously. It was originally developed to help in the identification and quantitation of halogenated pesticides commonly found on ginseng. It has now been refined to include many of the halogenated pesticides that are frequently detected on fresh produce which had previously been difficult to detect. The system uses a gas chromatograph coupled with a mass selective detector, which uses selected ion monitoring. Some of the pesticides commonly missed by halogen selective detectors that this new scheme will identify include certain pyrethroid insecticides and triazole fungicides as well as others. (Journal of AOAC International, Vol. 88, No. 5).
  • wpdoc9.gifOn November 16, the EPA released voluntary labeling guidelines to aid manufacturers in their effort to reduce resistance to pesticides. The guidelines provide examples of symbols and statements on avoiding pest resistance that could be added to product labels. The basic black on white narrow rectangle should appear in the upper right quadrant with the appropriate class, based on IRAC, HRAC, or FRAC groupings. These guidelines are similar to those in Canada, as well as those in Australia, which are mandatory. (Chemical Regulation Reporter, 11/28/05).
  • wpdoc10.gifFourteen transgenic food crops have been approved for contained and limited field trials in India. The trials are being conducted by both public and private sector institutions and target traits of the crops include insect tolerance, herbicide tolerance, viral and fungal resistance and stress tolerance. The transgenic food crops approved for contained field trials are the eggplant varieties developed by the Indian Agricultural Research Institute (IARI), Delhi and the Mumbai- based private seed company, Mahyco. IARI has developed the transgenic eggplant with the insertion of cry 1 Ab gene, while Mahyco has developed their variety with the insertion of cry 1 Ac gene. Mahyco and Sungrow Seeds Ltd, Delhi have developed their varieties of cauliflower with the insertion of cry 1 Ac gene and Sungrow Seeds has developed transgenic cabbage with the insertion of the same gene. (Financial Times, 10/17/05).
  • wpdoc11.gifOrganic food is a multibillion- dollar industry with growing pains it wants Congress to help soothe. At issue is whether small amounts of non-organic ingredients - vitamins, spices, citric acid, even carbonation - should be allowed in food bearing the "USDA Organic" seal. An appeals court decided earlier this year that none of those things belongs in food labeled as organic. Arthur Harvey, an organic blueberry farmer from Maine, sued the government in 2002 for allowing products containing synthetic ingredients to be sold as organic, among other things, stating, "The basic principle of the law is that anything labeled organic has to be 95 percent organic and 100 percent natural. I think that's a pretty simple principle." However, to make blueberries into jam, for example, or milk into yogurt, thickening usually requires pectin, and pectin comes from fruit peels, but because of how it's made, it's considered synthetic. That is why, over the years, the government has allowed pectin and dozens of other non-organic or synthetic ingredients into processed organic food. Food labeled "organic" must have at least 95 percent organic ingredients; exceptions for pectin and other ingredients apply to the other 5 percent. Nancy Hirshberg, a vice president at New Hampshire-based Stonyfield Farm, the biggest organic yogurt maker, was cited as saying the court ruling jeopardizes 90 percent of the company's products, and that if the ruling stands, Stonyfield will have to replace the organic seal with the phrase "made with organic ingredients," a less marketable claim, adding, "Consumers aren't interested. If we can't call it organic - and that means also charge the organic premium - can we really afford to make it as organic?" According to an industry estimate by the Organic Trade Association, the lawsuit will cost manufacturers $758 million in annual revenues. (AP, 10/25/05).
  • wpdoc12.gifMonsanto will release a new breed of soybeans in partnership with The Solae Co., a firm that is mostly owned by one of Monsanto's biggest competitors. Food company Solae is mostly owned by DuPont, the global technology corporation that also owns Pioneer Hi- Bred International, Inc. Partnering with Solae offers Monsanto a ready-made marketing machine for the new breed of soybeans. Solae processes and sells soy protein to 3,000 customers worldwide that make everything from health drinks to hamburgers. Monsanto will provide Solae a new strain of soybean that yields more flavorful protein and which is easier to mix into other products. (AP, 10/27/05).
  • wpdoc13.gifB.t. corn is designed to combat several lepidopteran larvae (caterpillars). However, corn fields are home to a good number of insects, some of them natural predators of caterpillars. It is these non-target arthropods which provide an ecological balance for any corn field, and which should not be affected by whatever pesticides might be used to control caterpillar infestations. Researchers investigated the effects B.t. corn would have on the seasonal abundance of Coleomegilla maculata (pink spotted lady beetle), Orius insidiosus (pirate bug), Chrysoperla carnea (green lacewing), Cycloneda munda (spotless ladybird beetle), and a specialist parasitoid, Macrocentrus cingulum (parasitoid wasp). By trapping the insects, they found that there was no significant difference in insect abundance of any of the generalist predators. However, adult densities of M. cingulum were reduced by as much as 60 percent in the presence of B.t. corn. They also found that the generalists were more affected by differences in crop phenology rather than differences between B.t. and non-B.t. corn. (Environmental Entomology, Oct. 2005).
  • wpdoc14.gifDon Cameron, who is believed to be the only grower of organic cotton in California, was cited as telling 45 visitors to his farm, most of them from Ventura-based Patagonia, about the global world of cotton production and the challenges to growing organic food and fiber, adding, "There is a lot more risk in growing organic.” The story explains that Patagonia, a maker of casual and outdoor clothing that has been a pioneer in use of organic cotton and wool, has used 100 percent organic fibers in its cotton clothing since 1996 and frequently sponsors visits with growers. Jill Dumain, director of environmental analysis at Patagonia, was quoted as saying, "We want our staff to 'get it,' to see it first hand. As a clothing company, we're so far removed from what it takes to make this, we're very removed from agriculture." Cameron, general manager for Terranova Ranch Inc., pointed out the farming enterprise also grows conventional cotton, in addition to its 80 acres of organic pima cotton, which has a long fiber and is considered to be high quality. He also pointed out the farm has biotech pima, adding, "I believe organic and biotech both have a place," and that growing genetically modified cotton also means less use of pesticides. Cameron said that growing organic crops - walnuts, cilantro, alfalfa, oat hay, and processing tomatoes - often involves hand-weeding, which means stoop labor that is costly. (The Fresno Bee, 10/29/05).
  • wpdoc15.gifA team in California developed a process utilizing a commercially available membrane bioreactor, in which rice cells produce substances that can be subsequently used as health care products. Cells are provided with a special piece of DNA, which contains the recipe for the desired substance. The cells then read off the DNA and produce the product. In order to maximize yields and facilitate harvesting the product, the team developed a process which utilizes a special type of bioreactor which consists of two separate compartments - one contains the cells, and the other the nutrients. The distinct arrangement allows nutrients to reach cells more easily, and the product, which is excreted from the cells into the medium, can be easily retrieved. To improve the efficiency of the bioreactor, the UC Davis research team utilized rice cells. The group succeeded in producing alpha-1-antitrypsin (AAT), which is normally made by human liver cells. AAT is of great importance in medicine. Its task is to inhibit protein-degrading substances - also known as proteases - in blood and other bodily fluids. Between proteases and their antagonists (most importantly AAT) there exists a subtle balance. In case of a AAT deficiency, an excess of proteases results. As protein is one of the main components in almost all tissues, severe tissue damages is often the consequence of AAT deficiencies, because the proteases are no longer kept in check. (Checkbiotech, 12/1/05).
  • wpdoc16.gifA newspaper in Canada recently tested potatoes for residues covering a total of 265 pesticides. None of the organic samples showed residues. However, the non- organic potatoes were also pesticide free. Consequently, consumers paid substantially more for the organic produce ($6.57 a kilogram compared with $3.92 a kilogram for non-organic) which was chemically equivalent to conventional potatoes. The newspaper had sought the advice of the testing facility’s senior chemist, who recommended testing the potatoes because of the greater chance of pesticides concentrating in tubers in the ground and because the spuds are harvested soonest after spring application of pesticides. (Vancouver Sun, 12/3/05).
  • wpdoc17.gifGlyphosate inhibits 5-enolpyruvyl shikimate 3-phosphate synthase, a key enzyme in the synthesis of aromatic amino acids in plants, fungi, and bacteria. Studies with glyphosate-resistant wheat have shown that glyphosate provided both preventive and curative activities against Puccinia striiformis f. sp. tritici and Puccinia triticina, which cause stripe and leaf rusts, respectively, in wheat. Growth-chamber studies demonstrated wheat rust control at multiple plant growth stages with a glyphosate spray dose typically recommended for weed control. Rust control was absent in formulation controls without glyphosate, dependent on systemic glyphosate concentrations in leaf tissues, and not mediated through induction of four common systemic acquired resistance genes. A field test with endemic stripe rust inoculum confirmed the activity of glyphosate pre- and postinfestation. Preliminary greenhouse studies also demonstrated that application of glyphosate in glyphosate-resistant soybeans suppressed Asian soybean rust, caused by Phakopsora pachyrhizi. (Proceedings of the National Academy of Science, 11/29/05).
  • wpdoc18.gifResearchers at Alabama A&M University recently announced they have successfully eliminated one major allergen in peanut that sometimes causes fatal reactions in people. There are at least six distinct peanut allergens that pose problems for certain people, according to the team. Using a process called RNA interference, the scientists were able to transform peanut tissues and silence the Ara h2 allergen gene, thus eliminating one of the proteins which triggers allergic reactions. Studies are under way to determine if the new transgenic peanut maintains similar nutritional qualities. (Huntsville Times, 12/5/05).

Back to Menu

Pesticide Information Office Main Menu