Abstract
Trichothecium roseum causes pink mold rot of muskmelons and tomatoes cultivated in greenhouses, and also produces trichothecin, a 12, 13-epoxytrichothecene. To clarify the pathogenicity and trichothecin production of T. roseum, mycological examination was carried out in 8 greenhouses in Chiba Prefecture. The contamination of muskmelon and tomato fruits with trichothecin was also examined. Trichothecium roseum was isolated from almost all of the moldy or discolored muskmelon and tomato fruits, as well as tomato stem dumped near the greenhouse. The fungus was found in the air of a greenhouse in which many moldy tomato fruits were present, but in none of the soil samples from the greenhouses tested. In an inoculation test, T. roseum isolated from muskmelon and tomato invaded and decayed the flesh of matured muskmelons. Moreover, almost all the isolates of T. roseum tested produced trichothecin on Czapek-Dox broth supplemented with 0.2% corn steep liquor cultured for 21 days at 25°C. Trichothecin was detected in moldy muskmelon and tomato fruits collected in the greenhouses.
