Submitted to: Journal of Sugarbeet Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/16/2008
Publication Date: 5/22/2008
Citation: Strausbaugh, C.A., Rearick, E., Camp, S. 2008. Influence of curly top and Poncho Beta on sugar beet storability. Journal of Sugarbeet Research. 45(1-2):31-47. Interpretive Summary: Preventing sugar losses in long-term storage and curly top in the field is important to the economic viability of the sugar beet industry. Curly top is an important viral disease problem worldwide. The primary means of controlling this disease is through host resistance. An insecticide seed treatment, Poncho Beta, has been able to reduce symptoms of curly top by at least 31%. However, even the best host resistance combined with the seed treatment will not completely eliminate symptoms. Curly top can lead to significant yield losses in the field but also the loss of sugar (5 to 8% averaged across cultivars) in long-term storage. These data show that selecting cultivars for resistance to curly top and storability to reduce sugar loss will be important.
Technical Abstract: Storage problems lead to considerable losses in sugarbeet production, which may be exacerbated by field disease problems such as curly top. To investigate the influence of curly top on storability during the 2005 and 2006 growing seasons, three sugarbeet cultivars varying for resistance to curly top were evaluated both with and without the insecticide seed treatment Poncho Beta (60 g a.i. clothianidin + 8 g a.i. beta-cyfluthrin/100,000 seed). At harvest, 8-beet samples from each cultivar were collected and placed inside an outdoor pile. Samples were removed at 40-day intervals beginning on 31 October in 2005 and 1 November in 2006. Sugar content, frozen and discolored root area, and root weight were evaluated. By mid-September plants from Poncho Beta treated seed had curly top ratings that were 37 and 31% lower (P < 0.0001) than plants from the untreated seed in 2005 and 2006, respectively. After 124 and 131 days in storage, roots from Poncho Beta treated seed when compared to roots from untreated seed had 8.5 and 5% more sucrose in 2005 and 2006, respectively. Cultivar choice and insecticide seed treatments will be important in limiting losses to curly top in the field, but also in long-term storage.