Sugar Beet Root Storage Properties Are Unaffected by Cercospora Leaf Spot

Cercospora leaf spot (CLS; causal agent Cercospora beticola
Sacc.) is endemic in many sugar beet production
regions due to the widespread distribution of C. beticola
and the inability of current management practices to provide
complete control of the disease. Roots harvested from
plants with CLS, therefore, are inevitably incorporated into
sugar beet root storage piles, even though the effects of
CLS on root storage properties are largely unknown. Research
was conducted to determine the effects of CLS on
storage properties including root respiration rate, sucrose
loss, invert sugar accumulation, loss in recoverable sucrose
yield, and changes in sucrose loss to molasses with respect
to CLS disease severity and storage duration. Roots were
obtained from plants with four levels of CLS severity in
each of three production years, stored at 5°C and 95% relative
humidity for up to 120 days, and evaluated for storage
characteristics after 30, 90, and 120 days storage. No
significant or repeatable effects of CLS on root respiration
rate, sucrose loss, invert sugar accumulation, loss in recoverable
sucrose yield, or change in sucrose loss to molasses
were detected after 30, 90, or 120 days storage regardless
of the severity of CLS disease symptoms. Therefore, no
evidence was found that CLS accelerates sugar beet storage
losses, and it is concluded that roots harvested from
plants with CLS can be stored without additional or specialized
precaution, regardless of CLS symptom severity.