Khalil I. Al-Mughrabi, A. Vikram and R. Poirier
Partner: Potatoes New Brunswick
Abstract: Dry rot, black scurf and common scab are three potato diseases of economic importance throughout the world. Field trials
conducted in 2005 and 2006 in New Brunswick assessed the efficacy of saponins extracted from Chenopodium quinoa (SCQ; HeadsUp®) used as
foliar or seed treatments. Trials consisted of: 1) untreated, inoculated or infected control; 2) seed inoculated or infected and treated
with SCQ; 3) seed inoculated or infected and the foliage treated with SCQ; and 4) seed inoculated or infected and treated with Maxim® PSP.
After harvest, tubers were assessed for the severity of dry rot, black scurf and common scab. Tubers were sized and weighed and assessed
for disease severities. All treatments significantly reduced the severity of dry rot by 32.4-46.7%; common scab by approximately 30%; and black scurf
by 61.2-76.5% relative to the untreated, inoculated/infected controls. Seed and foliar treatments with SCQ increased the total yield compared
to the untreated, inoculated/ infected control. Seed treatment with SCQ increased marketable yield by 23.8-26.2% while foliar treatment
increased marketable yield by 16.8-23.8%. Results indicate that saponins from C. quinoa can be used as a potentially viable option for managing
dry rot, black scurf and common scab diseases of potato.