Potato tuber lenticels: susceptibility to infection by Erwinia carotovora var. atroseptica and Phytophthora infestans

SUMMARY In laboratory tests, proliferation increased the susceptibility of lenticels on mature tubers to infection by Erwinia carotovora var. atroseptica. No differences in susceptibility to E. c. atroseptica and Phytophthora infestans were detected on tubers lifted at different stages of growth from soil kept wet or dry for 3 wk prior to each sampling. As tubers aged, fewer lenticels became infected by either pathogen or were penetrated by fluorescein dye, presumably because cells had been suberized and cork barriers formed.