Brief Summary of Minutes of Annual Meeting

No annual meeting was held this year due to time and funding constraints by numerous individuals. Reports on curly top in western states were solicited from previous participants. Rod Clark, CDFA, sent an extensive report (see full report below) on the curly top virus control program in California. A dry summer and fall produced few beet leafhoppers in the Central and Imperial Valleys. The extreme drought did not support sustained growth of weed hosts of the leafhoppers. Minimal sprays were made to roadside weed hosts. Disease symptoms of curly top were not seen in commercial fields of tomatoes or peppers. Bill Wintermantel finished up work on Beet severe curly top virus and Beet mild curly top virus. The research project focused on the importance of specific hosts as virus reservoirs that contribute to movement of virus into host crops. He made a video on curly top viruses on tomato, which is available through Plant Management Network at www.plantmanagementnetwork.org/edcenter/seminars/tomato/curlytop/ Phil Miklas does not have any active research projects on curly top virus. For Washington in 2012, curly top incidence in beans has been very low. He is interested in the aspect of major genes and minor genes with broad spectrum resistance against different Geminivirus species such as Bct gene effective against both curly top and bean dwarf pub in Plant Dis 93:645-648. Bct being a dominant gene with linked markers is an attractive set up for candidate gene discovery given the new genomic tools available in bean for which the whole genome sequence was recently released, and large SNP panels will soon be available. Bob Hammon, Colorado Extension, tested the impact of foliar/soil applications with Scorpion  dinotefuran on tomato. Erik Wenninger reported a little bit of natural curly top pressure this year on the Kimberly, ID research farm. Only BSCTV and BCTV were found, but not BMCTV, in those plants. He sent a report (see below) of results from a beet leafhopper / curly top insecticide trial carried out by Carl Strausbaugh, Imad Eujayl, and himself last year. This work was part of a publication in Plant Disease that is listed below. They are conducting a similar trial this year that includes more foliar sprays with and without seed treatment; some of the foliars look very promising, but will wait to report on those results. They are also working on developing separate beet leafhopper colonies that have a single virus species or are virus-free in order to examine beet response to individual virus species. Rebecca Creamer reported a medium low curly top year for southern New Mexico. She has three active curly top projects, one looking at competitive inhibition between curtoviruses, a second studying the role of endosymbionts in leafhopper transmission of curtoviruses, and the third dealing with methods for monitoring leafhopper movement and identification of key weed hosts.

Collaborative curly top projects for 2012 were carried out between Rebecca Creamer and Robert Gilbertson, and between CDFA (Rod Clark) and Bill Wintermantel.

Strausbaugh, C.A. and Wenninger, E.J. and Eujayl, Imad A. 2012. Management of Severe Curly Top in Sugar Beet with Insecticides. Plant Disease 96:1159-1164. Sedano, M., Lam, N., Escobar, I., Cross, T., Hanson, S. F., and Creamer, R. 2012. Application of vascular puncture for evaluation of curtovirus resistance in chile pepper and tomato. Journal of Phytopathology 160:120-128. Wintermantel, W.M. 2012. Curly Top Disease of Tomato. Plant Management Network. Available: http://www.plantmanagementnetwork.org/edcenter/seminars/Tomato/curlytop.