Abstract: Results from investigations over 5 years (1986-1990) indicated that the yield loss of corn resistant or susceptible inbred lines were 21% and 35%higher in the epidemic years than those in the ordinary years respectively.The factor of sunshine hours was more important to the occurrence of the disease than other climatic factors. Under similar climatic conditions, the yield loss of the susceptible lines was 52%-82% higher than that of the resistant lines.For susceptible varieties, the yield loss of corn caused by ear rot disease is more serious than under unfavourable meteorological conditions.

Key words: Corn ear rot disease, Fusarium monlliforme, Yield loss, Varieties, climatic factor