IPM National News
Efforts to Stave Off Bt Resistance
Researchers at the University of Mexico and University of Arizona have modified the Bt toxins produced by Bacillus thuringiensis. Unlike the natural toxins, the "new" toxins do not need to bind to a receptor on the host insect to kill it. Although resistance to the Bt toxins is rare (only two cases exist), most believe that more and more insects will develop resistance as Bt use increases. These modified Bt toxins will significantly reduce the chances of insects developing resistance.
Spinach Plants Tolerant of Leafminer Attack
Agriculture Research Service geneticists have bred two strains of spinach plants that have shown tolerance to attack by leafminers. Compared to control plants, the new spinach cultivars showed significantly fewer mines. Natural plant resistance to insect attack results in lowered pesticide use.
Pest Management Strategic Plans
The Western IPM Center (one of four regional pest management networks in the U.S.) produces Pest Management Strategic Plans that address pest management needs of specific crops for individual states or regions. The newest plans include a revised plan for potatoes, and a new plan for non-rangeland forages (excluding alfalfa). A new plan for sweet cherries should be available soon. All plans may be viewed at http://pestdata.ncsu.edu/pmsp/.
Protecting Bees from Small Hive Beetles
Small hive beetles have been in the eastern U.S. since the late 1990s causing damage to honey bee hives. The beetles lay their eggs in cracks and crevices within the hive, and the larvae tunnel through the comb, destroying the honey and pollen. The honey bees eventually vacate the hive.
Entomologists in Gainesville, FL, have developed a trap baited with yeast that lures these beetles away from the hive. The traps are targeted to small-scale beekeepers because they need to be cleaned regularly. Once in use, they should significantly reduce the honey and bee colony losses caused by small hive beetles.
Herbicidal Compound Discovered in Common Fescue
Scientists have long known that certain varieties of common fescue, when grown in certain environmental conditions, produce natural herbicidal compounds, and release them from their roots. Recently, chemists at Cornell University identified the herbicide as an amino acid called meta-tyrosine. The amino acid was shown to be safe to mammals, fungi, and bacteria. The mode of action on broadleaved plants is unknown. The next step is to breed new lines of fescue that more effectively inhibit weed growth.
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