Title: Update on the potato variety screening for zebra chip resistance trial Authors
|Buchman, J -|
|Bester, G -|
|Miller, C -|
|Van Hest, P -|
|Nordgaard, J -|
|Yilma, S -|
Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: December 16, 2012
Publication Date: June 7, 2013
Citation: Munyaneza, J.E., Buchman, J.L., Bester, G., Novy, R.G., Miller, C., Van Hest, P., Nordgaard, J., Yilma, S., Wallis, C.M. 2013. Update on the potato variety screening for zebra chip resistance trial. In: Proceedings of the 12th Annual SCRI Zebra Chip Reporting Session, ed. F.Workneh, A.Rashed, and C.M. Rush, San Antonio, TX (October 30-November 2, 2012. pp 122-124. Interpretive Summary: Zebra chip, an economically important disease of potato in U.S., Mexico, Central America and New Zealand, is caused by the bacterium Liberibacter transmitted to potato by the potato psyllid vector. Identification of potato varieties with resistance to zebra chip is crucial to development of effective and sustainable management strategies for this disease. In collaboration with potato breeders, researchers at USDA-ARS Wapato, WA assessed several potato varieties and advanced breeding line for zebra chip resistance. It was discovered that some potato breeding lines showed some resistance to zebra chip. This information will assist potato producers reduce damage caused by zebra chip by selecting and planting varieties that are less vulnerable to the disease.
Technical Abstract: Zebra chip (ZC), a new and economically important disease of potato has caused millions of dollars in losses to the potato industry in the Americas and New Zealand. The disease is associated with the bacterium “Candidatus liberibacter solanacearum” (Lso) that is transmitted to potato by the potato psyllid, Bactericera cockerelli. In U.S., the disease had been limited to southwestern and central states but spread to the Pacific Northwest in 2011. Currently, the only means to manage ZC is by controlling its psyllid vector with insecticide applications. Identification of ZC-resistant or tolerant varieties may offer the most efficient and useful way to manage this disease. Five promising advanced breeding lines identified in two previous screening trials were further evaluated for ZC resistance under controlled field cage conditions by exposing the plants to Lso-infective psyllids in 2012 at the USDA-ARS facility in Wapato, WA. Although plants from all of the tested plant material developed ZC foliar symptoms, none of the five evaluated lines were observed to have freshly-cut ZC symptoms, while Atlantic tubers from the same study were highly symptomatic. Upon frying, Atlantic and the line BS2 had moderate to severe ZC, whereas the lines 00-3115-2 and ZC73 had minor ZC symptoms, and 00-3115-11 and ZC74 exhibited no disease symptoms at all. In addition, PCR analyses showed that inoculated Atlantic had much greater Lso titers than the other varieties. The results suggest that these potato lines may be resistant to or tolerant of ZC and warrant further evaluation.