Determination of Wheat Varieties Tolerant to Spot Blotch Disease, Bipolaris sorokiniana (Sacc.) Shoem. Akram Mohd., Singh Amerika1 Centre of Advance Strudies in Plant Pathology, College of Agriculture, G.B.P.U.A & T., Pantnagar, 263145 1N.C.I.P.M., L.B.S. Budding, I.A.R.I., New Delhi, 110012, India Abstract Three sprays of tilt (propiconazole) @ 0.05% 25 EC/ha protected the wheat varieties from spot blotch and their yielding potential without any significant disease interference. The disease seventy did not differ significantly in protected plots of almost all the varieties. Thus, the protected plots could be considered disease free Disease severity (A-value) on flag leaf, % loss in yield and 1000-grain weight of artificially inoculated-unprotected plots as compared to fungicide protected plots were considered as reliable parameters for identification of relatively tolerant varieties in field conditions. Wheat varieties HUW 206, UP 262, UP 2121, PBW 299 and UP 2338 proved to be relatively tolerant as these suffered less loss in yield (8.5 to 15.8%) and 1000-grain weight (7.3 to 15.1%) in spite of equivalnt disease severity (58.5 to 67.6%) as compared to their respective checks i.e. UP 115, HD 2329, HUW 895 and Kalyansona (yield loss 18.7 to 33.5% and 1000 grain weight loss 17.5 to 29.2%). Top Keywords Bipolaris sorokiniana, Tolerance, Triticum aestivum. Top |