Over the past few years, the potato production of US, Mexico, New Zealand and Central America has been under threat by Zebra Chip (ZC), a disease associated with the Candidatus Liberibacter solanacearum bacteria, vectored by the potato psyllid (Bactericera cockerelli). The disease turns part of the amide in soluble sugars so, when potatoes are cooked, sugars caramelise and streaks appear. Of course ZC is currently monitored with pesticides, but sustainable defence requires the development of resistant and/or tolerant varieties. Entomologists from the University of California Riverside, together with researchers from INIFAP (Mexico), characterised four promising potato lines (246, 865, 510, NAU) exposed to Cls-positive adult psyllids and monitored the vector’s behaviour towards the plants and the effects of the bacteria on the tubers. The potato lines were compared to ZC-susceptible variety Atlantic. More