Abstract: In 1998, Indian regulatory agencies approved the registration of CGA 184927, MON 37500, and fenoxaprop for postemergence control of isoproturon-resistant littleseed canarygrass. Herbicides used in rice and wheat before 1998 were generally mixed with sand or urea and were applied by hand. Foliar pesticide spray applications consisted primarily of insecticides and fungicides that were applied to high-value crops. These pesticides were often sprayed to runoff with backpack sprayers that were equipped with single hollow-cone or flood nozzles. Applicators walked through the fields, swinging the wands in sweeping motions resulting in uneven pesticide distribution and overapplication. The newly registered postemergence herbicides were applied with the same equipment and in the same fashion. After these applications, control of littleseed canarygrass was strikingly inconsistent, and the growers blamed the lack of control on the manufacturers. It was later clear that basic understanding of the application techniques was lacking. In response to this, an application training workshop was organized and conducted in India and Nepal in 2000. The workshops focused on teaching the participants how to use and fabricate multiple-nozzle booms, the importance of flat-fan nozzles, calibration, drift avoidance, and applicator safety. To date, approximately 3,000 farmers, extension agents, scientists, and industry representatives have attended more than 30 workshops. The participants were unanimously enthusiastic about the value of the workshops. Although simplistic, the adoption of this technology will significantly decrease the amounts of herbicides applied and will increase efficacy and efficiency.
Nomenclature: CGA 184927 (proposed common name, clodinafop), 2-propynyl R-2-[4-[(5-chloro-3-fluoro-2-pyrdinyl)oxy]phenoxyl]-propanoate propynyl ester; fenoxaprop; isoproturon; MON 37500 (proposed common name, sulfosulfuron), 1-(4,6-dimethoxypyrimidin-2-yl)-3-[(2-ethanesulfonyl-imidazo[1,2-a]pyridine)sulfonyl]urea; littleseed canarygrass, Phalaris minor Retz. #3 PHAMI; rice, Oryza sativa L.; wheat, Triticum aestivum L.
Additional index words: Backpack sprayers, pesticide application method, technology transfer.
Abbreviation: I-HRAC, The Herbicide Resistance Action Committee of India.