Survey of sesame crop in the cultivators´ field in the district of Daejeon, Yuseong, Sintanjin, Nonsan and Keumsan revealed that Alternaria and Corynespora blights of sesame were wide spread and caused severe damage to sesame plants.
Symptoms of a new disease of sesame in Korea caused by Alteraria sesami were spreading, dark-brown to black, water-soaked lesions which often could be traced the entire length of the stem. In severe infections, several lesions coalesced together involving a major portion of the blade and the infected leaves dried and usually dropped off.
Symptoms of Corynespora blight, caused by Corynespora cassiicola, were irregular shaped, concentricallyzoned, light brown to reddish brown lesions which later coalesced and caused defoliation. Stem lesions were long, reddish brown streaks that often coalesced, blighting the plants.
The optimum temperatures for mycelial growth of A. sesami and C. cassiicola were about 27℃ and sporulations of these 2 fungi were stimulated under alternating light and darkness. Mycelial growth and sporulation of A. sesami and C. cassiicola were the greatest on sesame oatmeal agar (SOA) and potato dextrose agar(PDA), respectively.
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