ESTIMATION OF YIELD LOSSES IN CORN DUE TO STALK ROT PATHOGENS

Pathogenicity of Fusarium moniliforme, F. graminearum and Macrophomina phaseolina isolated from stalk rot disease of corn were tested on a s usceptible corn cv. Shaheen in different seasons and at different stag es of plant growth at the National Agricultural Research Centre (NARC) , Islamabad, Pakistan. F. moniliforme and M. phaseolina in combination produced 77.9 and 89.0% infection with respectively 21.7 and 25.9% re duction in grain yield during spring and summer seasons of 1988, where as F. graminearum produced 32.8 and 49.4% disease severity with 0.9 an d 1.4% reduction in grain yield during the same spring and summer seas ons.