Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: May 13, 2013
Publication Date: June 1, 2013
Citation: Strausbaugh, C.A., Wenninger, E.J., Eujayl, I.A. 2013. Management of curly top in sugar beet with seed and foliar insecticides. Phytopathology. 103:S2.139-140. Technical Abstract: Curly top in sugar beet can result in severe yield losses and is caused by Beet severe curly top virus (BSCTV) and other closely related Curtovirus spp. which are vectored by the beet leafhopper. Neonicotinoid seed treatments (Cruiser, NipsIt, and Poncho) have been shown to be an effective supplement to host resistance, but measures to extend control beyond the duration of seed treatment efficacy needs to be investigated. In 2012, a field study was arranged in a randomized complete block design with 8 replications and planted with the cultivar B-42. The 16 treatments included untreated and Poncho Beta treated seed with and without 6 foliar insecticides (applied 7 days before and 6 days after release of viruliferous beet leafhopper) and just Poncho and Poncho Votivo treated seed. On 22 Jun (59 days after planting), 6 beet leafhoppers per plant were released to ensure good disease pressure. Visual foliar ratings on the 15 Aug and 15 Sep indicated some seed and foliar treatments reduced (P < 0.0001) symptoms by 13 - 60% compared to the check. Root yields were increased (P < 0.0001) by 8 - 18% compared to the check. Estimated recoverable sucrose was increased (P < 0.0001) by 12 - 21% compared to the check. After the seed treatments lose efficacy, it would appear that the pyrethroid insecticides Asana and Mustang may be applied to help reduce curly top and aid in the control of other pests and insecticide resistance management.