Fungicide Sensitivity of f. sp. and Affecting Lentil in the Northern Great Plains.

f. sp. and cause wilting and root rot in pulse crops including lentil. Fungicide seed treatments are widely used, but information about spp. sensitivity in lentils is limited. Here, 30 f. sp. and 30 isolates from Montana, southern Canada, North Dakota, and Washington were identified, tested for pathogenicity, and assayed for in vitro sensitivity to pyraclostrobin, prothioconazole, ipconazole, and thiophanate-methyl. f. sp. and differed in their sensitivity to all fungicides. No resistant isolates were identified, but f. sp. had lower EC values in pyraclostrobin (averaging 0.47 μg a.i./ml) than (averaging 0.89 μg a.i./ml) for mycelia assays. Both species had lower EC values in prothioconazole, averaging EC 0.23 in f. sp. and 0.53 μg a.i./ml in . . f. sp. isolates had the lowest EC values on ipconazole compared to (0.78 and 1.49 μg a.i./ml). The pathogens were least sensitive to thiophanate-methyl (1.74 μg a.i./ml for . f. sp. and 1.91 μg a.i./ml for ). Overall sensitivity to the fungicides was higher in f. sp. than . This study provides reference EC values while pointing to the possibility of differential fungicide efficacies on spp. This will be helpful to monitor shifts in sensitivity of spp. and devise robust root rot/wilt management approaches.