1Central Potato Research Institute, Shimla, 171 001, (HP).
2Central Potato Research Institute Campus, Modipuram, 250 110, (UP).
3Onkar Cottage, Behind KN Hospital, Shimla, 171 001, (HP).
Twenty-nine cultures of B-population were field-evaluated for resistance to late blight and yield. Out of 10 cultures evaluated in replicated trial, 6 showed high degree of resistance to late blight (DI 5–10%), and from 19 cultures, tested under duplicate observational rows, 15 showed very high degree of resistance (grade 3). The results indicated that B-population is a big reservoir of field resistance to late blight.