Comparison Of Esterase Release From Ungerminated Spores Of Virulent And Avirulent Isolates Of Chalara elegans Nag Raj and Kendrick

ABSTRACT Wattimena, S.Ch. 2006. Comparison of esterase release from ungerminated spores of virulent and avirulent isolates of Chalara elegans. Berkala Ilmiah Biologi 5 (1) : 23 - 31. Chalara elegans Nag Raj and Kendrick (syn. Thielaviopsis basicola (Berk, and Br.) Ferr.) is a fungal pathogen that causes black root rot disease on many plant species. The ability of virulent and avirulent isolates of C elegans to release nonspecific esterase was studied. Virulent isolates (BK28, BC94PA, NC49A, HRB, AK208, CKP, AK89) released esterase after 45 minutes of contact with an artificial (plastic wrap) surface whereas avirulent isolates (BK28R, BK101, BK102, WASH, FL/W) did not released esterase after 45 minutes of contact with an artificial (plastic wrap) surface. This result suggests that esterase may be important in the penetration process of C. elegans. Low temperature (5°C) reduced the ability of a virulent isolate of C. elegans (BK28) to release esterase on plastic wrap. While growing on V8 juice agar, virulent isolates released significantly more esterase than avirulent isolates. Keywords : Esterase, avirulent and virulent isolates, Chalara elegans Nag Raj and Kendric