|Gupta, Sanjay - UNIV OF MINNESOTA|
|Sowokinos, Joesph - UNIV OF MINNESOTA|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 28, 2008
Publication Date: April 1, 2009
Citation: Gupta, S.K., Glynn, M.T., Sowokinos, J.R. 2009. Screening of Advanced Potato Breeding Clones for Resistance to Cold-Induced-Sweetening (CIS) [abstract]. American Journal of Potato Research. 86(2):144. Technical Abstract: The advantages of processing potatoes from low temperature storage are well known. It had previously been reported that clones with A-II isozymes of UDP-glucose pyrophosphorylase (UGPase) and low vacuolar acid invertase (VAcInv) activity demonstrate increased resistance to CIS. This study reports on techniques to increase the efficiency and to decrease analysis time for evaluating potato breeding populations for the presence of these two markers. Analysis of A-II isozymes was accelerated by using pre-cast gels. A new micro-plate reader based assay system for VAcInv allowed for the analysis of forty samples per day. Sugars and chip color were determined using the YSI-2700, Industrial Sugar Analyzer and the D25 Hunter Reflectometer, respectively. One hundred and forty potato clones were evaluated over a two year period. It was verified that clones with low VAcInv activity (both basal and total) and the A-II isozymes of UGPase showed greater resistance to CIS. A significant correlation between glucose-forming-potential (GFP=Glc/Suc) and acceptable color was observed when an upper limit was placed on sucrose content. Clones with high sucrose generally had an excess of glucose and dark chip color regardless of the amount of VAcInv. The screening of breeding clones for VAcInv activity and A-II isozymes of UGPase described here could accelerate the selection of superior storage and processing potatoes as well as aid in the selection of parental material used in future matings.