Fourth International Bemisia Workshop International Whitefly Genomics Workshop
DuPont Rynaxypyr™ (DPX-E2Y45): A Novel Anthranilamide Insecticide for Managing Bemisia tabaci and Interfering with Transmission of Tomato Yellow Leaf Curl Virus on Tomato Transplants
1 University of Florida/IFAS, Gulf Coast Research & Education Center, Wimauma, FL, USA. Correspondence: dschust@ufl.edu
2 Dupont Crop Protection, Raleigh, NC, USA
3 Dupont Crop Protection, Stine-Haskell Research Center, Newark, DE, USA
Rynaxypyr™ (DPX-E2Y45) is a novel insecticide from the anthranilamide class of chemistry, discovered and being commercialized by Dupont Crop Protection. This new insecticide provides effective control and good residual activity against a broad spectrum of economically important pest species at low use rates. Greenhouse studies were conducted to determine the efficacy of Rynaxypyr™ in controlling Bemisia tabaci biotype B and in preventing transmission of the begomovirus Tomato yellow leaf curl virus (TYLCV). Tomato seedlings were grown in transplant trays and, at the 2-leaf stage, insecticide treatments were applied either as soil drenches or foliar applications. (I) To evaluate the direct effects of the treatments on adult whitefly mortality, insecticide treated seedlings were transplanted into pots (7 days after the drench treatment or 1 day after the foliar treatment). Ten non-virulent whitefly adults were confined on one leaf of each plant in clip cages and the number of surviving adults was counted daily for 3 days. (II) To evaluate the indirect effects on inhibition of virus transmission, treated plants were exposed to virulent TYLCV whitefly adults in organdy cages for 3 days, after which adults were removed. Plants were held for an additional 3 weeks and were periodically inspected for obvious TYLCV symptoms. The presence or absence of TYLCV was confirmed by PCR using TYLCV specific primers. Rynaxypyr™ was not as effective as the standard pymetrozine as a foliar spray or the standard imidacloprid as a drench in killing whitefly adults and in reducing TYLCV transmission. Nevertheless, the level of suppression provided by foliarly applied Rynaxypyr™ was significant and comparable to current control levels observed with neonicotinoids in the field. These data justify inclusion of this novel insecticide with a new mode of action for foliar chemical rotations and alternative drench treatments as part of a resistance management program.
|
PREVIOUS Monitoring of Imidacloprid Resistance in Biotype B of Bemisia tabaci in Florida |
NEXT Management of Bemisia, TYLCV, and Insecticide Resistance in Florida Vegetables |