b'Andys Advice:Keep An Eye OnPotato Pink EyeBy Andy Robinson, Extension Potato Agronomist, NDSU/UMNdisorder is the death of meristemat- Maintain a healthy canopy to keepicperidermcells.Asaresult,this tubers cooler. leads to the loss of periderm integri-ty, causing abnormal internal suber-ization. Because the periderm doesnot fully heal, it can be gateway forsecondarypathogensandcausetubers to dehydrate quickly. TubersthatarestoredwithPinkeyecanbecome infected with tuber diseasessuch as fusarium dry rot or bacterialsoft rot in storage. Ifthisdisorderisrecognizedinfieldspriortoharvestsomesteps Figure 1. Pink eye expressed in eyesThis past year there were numerous can be taken to mitigate the effects near the bud-end of the tuber. cases of Pink eye. This is a physio- thiscouldhaveonthecrop.Tologicaldisordermostconsistently reducedproblemscausedbyPinkcaused by excessive moisture, warm eye use careful handling practices totemperatures, loss of foliar canopy reduce injury to tubers during har-andsoilcompaction.Thissyn- vest and handling. Try not to storedrome gets its name because it can tubers or minimize storage length.be expressed as a pinkish color and Ifstoringusecoolanddrycondi-raisedareasonthetubersurface tionstopreventthespreadof(Figure 1). In some cases, Pink eye pathogens. Figure 2. Pink eye (Periderm Disordercan develop into corky areas on the Syndrome) expressed as a pinkish dis-tuberskin,oftendescribedasele- Ifthisisanoccurringproblemin coloration and corky patches. phant hide or corky patch (Figure 2 specific fields or areas of fields, thereand 3). In these cases, a pink color is are some management options thatnotexpressed;hence,thename havebeenidentified.Trytomini-changesuggestiontoPeriderm mize water-saturated soils by usingDisorderSyndromewasrecently deep tillage and planting higher ingiven by Dr. Ed Lulai. This disorder the hill. Consider not planting areashasbeendescribedtostartatthe wherethereishighcompaction,bud-end of the tuber. suchasfieldentrancesandhead-lands,andavoidlowspotsinthe Figure3.PeridermDisorderSyn-The problem with this physiological fieldwherewatercanaccumulate. drome(pinkeye)causingcorkypatches on tuber skin.12 POTATO GROWER NOVEMBER/DECEMBER 2019'