Submitted to: Journal of Sugar Beet Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 26, 2010
Publication Date: February 7, 2011
Citation: Strausbaugh, C.A., Rearick, E., Eujayl, I.A., Foote, P. 2011. Effect of insecticide seed treatments improve sugarbeet storability. Journal of Sugar Beet Research. 47(3&4):65-88 (DOI: 10.5274/jsbr47.3.65). Interpretive Summary: The loss of sugarbeet root tonnage and sucrose in storage costs the industry tens of millions of dollars annually. To control sucrose losses in sugarbeet roots under ambient storage conditions will take an integrated approach. Some of the major factors influencing sucrose loss in sugarbeet roots include temperature, root health at harvest, respiration, excessive microbial growth and moisture loss, damage during harvest and transport, and the amount of soil, weeds, and debris going into piles. The primary response of the sugarbeet industry to control losses in storage has been the use of physical control measures, but these only address part of the problem. Additional integrated controls such as selecting roots for less respiration, improving resistance to microbial growth, and storing only healthy roots also need consideration. The influence of field disease problems has been under investigation, but the influence of pest pressure in the field on the sugarbeet storability has been given limited attention. Recently the use of an insecticide seed treatment proved effective in controlling the beet leafhopper and subsequently limiting the presence of curly top viruses in the sugarbeet roots so that storability could be improved. Given the wide influence of clothianidin on numerous insect pest problems, this insecticide applied as a seed treatment could potentially allow for improved storability through widespread pest control or suppression. Thus the objective of this study was to investigate the possibility that insecticidal seed treatments could provide enough control and/or suppression of insect pests throughout the growing season, to improve the storability of sugarbeet roots without the influence of disease problems. With natural pest pressure and the absence of plant disease, the insecticide seed treatment Poncho Beta and at times Cruiser Tef allowed for the production of sugarbeet roots that frequently stored (significantly and/or in ranking) better than the non-treated check for most storage variables measured. Across six sampling-dates, Poncho Beta was always ranked first for recoverable sucrose and was better than the non-treated check (17% more sucrose) when significant differences were present.
Technical Abstract: Sucrose loss in sugarbeet storage is a concern for all roots, but particularly those stored under ambient conditions. In order to control or suppress insect issues in sugarbeet production and consequently improve root storability, two neonicotinoid seed treatments, Poncho Beta (60 g a.i. [active ingredient] clothianidin + 8 g a.i. beta-cyfluthrin/100,000 seeds) and Cruiser Tef (60 g a.i. thiamethoxam + 8 g a.i. tefluthrin/100,000 seeds), were used to produce roots from four commercial sugarbeet cultivars grown in Declo, ID. At harvest, eight-beet samples from each cultivar-treatment combination were collected and placed inside an outdoor pile. Samples were removed on approximately 30-day intervals beginning on December 6 and 8 in 2008 and 2009, respectively. Discolored and frozen root area, weight and sucrose reduction, and sucrose yield were evaluated. Across six-sampling dates, Poncho Beta was always ranked first for recoverable sucrose and performed well for the other variables assessed. Over the three sampling-dates when Poncho Beta was significantly better (P < 0.10) than the non-treated check, recoverable sucrose was increased by an average of 17%. Cruiser Tef tended to rank intermediate between Poncho Beta and the non-treated check for recoverable sucrose and other variables. The insecticide seed treatments not only have the potential limit yield losses and increase profits in the field, but also improve sucrose recovery in storage.