New Epidemic Rots on Fruit, Stem, and Root of Paprika Caused by Nectria hematococca

Since 2000, severe rots on aerial and underground parts of paprika( Capsicum annum L.) has occurred in most cultivation glasshouses throughout the country. Totally 169 isolates of a fungus were consistently isolated from the diseased plant tissues of fruits, stems, branches, and roots collected from 19 farms in six provinces. Anamorph stage of the fungus was identified as Fusarium solani based on morphological characteristics. However, the fungus readily produced sexual structure of perithecia on infected plant tissues and on agar medium. Since the fungus formed abundant perithecia by single isolate, it was considered as a homothallic strain of Nectria hematococn, the teleomorph of F. solani. Irregularly globose perithecia with orange to red color formed sparsely to gregariously on dead tissues of fruits and basal stems at the 3ate infection stage, which is a diagnostic sign for the disease. Abundancy of perithecium varied among isolates and they sized 125-220$\mu\textrm{m}$ in diam. Asci enveloping eight ascospores were cylindrical and measured 60-80x8-12$\mu\textrm{m}$. Ellipsoid to obovate ascospores are two-celled and measured 11-l8${\times}$4-7$\mu\textrm{m}$. Ascospores are hyaline, slightly constricted at the central septum, and revealed longitudinal striations that is a typical trait of the species. This fungus that has never been reported in Korea previously became a threat to paprika cultivation because of its strong pathogenicity and nationwide distribution.