Impact of Cercospora leaf spot disease severity on sugarbeet root storage

Authors: Fugate, Karen; Eide, John; HAKK, PETER - North Dakota State University; LAFTA, ABBAS - North Dakota State University; KHAN, MOHAMED - North Dakota State University

Submitted to: Sugarbeet Research and Extension Reports
Publication Type: Proceedings
Publication Acceptance Date: 1/14/2021
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Cercospora leaf spot (CLS), caused by the fungus Cercospora beticola, is the most damaging foliar disease of sugarbeet in North Dakota and Minnesota. Historically, fungicides have been used to control disease symptoms. However, C. beticola has developed tolerance to several fungicides used against this disease, increasing the likelihood that disease symptoms will develop during production and that roots harvested from CLS-diseased plants will be incorporated into storage piles. It is suspected that roots harvested from CLS-diseased plants do not store as well as healthy roots. However, the effects of CLS on storage properties such as respiration rate, sucrose loss, loss in recoverable sugar, and the accumulation of invert sugars and other impurities that increase sucrose loss to molasses are unknown. Research was initiated in 2018 and continued in 2020 to determine the impact of different levels of CLS disease severity on sugarbeet root storage properties after short- and long-term storage. Roots with varying levels of CLS disease severity were obtained from a field that was inoculated with C. beticola and contained plots that received different number and types of fungicide treatments. From these plots, roots with four levels of severity of CLS symptoms were selected and placed into storage at 5°C and 95% relative humidity for up to 120 days. To date, no adverse effect of CLS on root storage properties has been observed, regardless of the severity of CLS symptoms. However, this research is ongoing and current results should be considered preliminary.