Long-day-adapted Solanum phureja as a source of resistance to blackleg caused by Erwinia carotovora subsp atroseptica

Long-day-adapted Solanum phureja clones were assessed for resistance to bla ckleg caused by Erwinia catoiovora subsp. atroseptica under field and contr olled environmental conditions over two years. In the held, twenty-two of t he twenty-three clones of S. phureja assessed were as resistant to blackleg as the commercial cultivar Ailsa, the most resistant control, and were sig nificantly (P<0.001) more resistant than the intermediate and susceptible c ultivars Wilja and Estima, respectively. Under controlled environmental con ditions, resistance in commercial cultivars was more easily overcome. Howev er, 18 of the 21 S. phureja clones assessed were significantly more resista nt to blackleg than these cultivars.