The occurrence of pink mold rot fungus Trichothecium roseum on tomatoes in Korea

Abstract

Trichothecium roseum DUCC502 was isolated from leaves of tomato plants at a greenhouse located in Buyeo, Chungchungnamdo. The colony color of the isolate was white initially and became pale pink on potato dextrose agar and oatmeal agar. Conidiophores of the isolate were long and slender, unbranched, and 73 – 112 x 2.1 – 3.3 µm in size. Its conidia were two-celled, hyaline colored, and ovoid or ellipsoid shaped, and11 – 18.3 x 6.1 – 8.5 µm in size. The 28S rDNA sequence analysis of the isolate showed it shared 99% similarity with that of T. roseum CBS113334. Mycelia of the isolate grew well on PDA plates under the conditions of pH 7–9 and temperature 20–25℃, respectively. A pathogenicity test showed the isolate caused necrotic regions and produced white to pale pink mycelia with spores on the surface of tomato fruits and leaves. This fungus was sensitive to benomyl and tebuconazole but less sensitive to dimethomorph, triflumizole and azoxystobin at 10 ug/ml concentration. Key words: Fungicide sensitivity, pink mold rot, postharvest disease, tomato,Trichothecium roseum.