Comparative Studies of Two Mucor Species Causing Postharvest Decay of Tomato and Their Control. Harold E. Moline, Research Plant Pathologist, USDA, ARS, HSI, Horticultural Crops Quality Laboratory, Beltsville, MD 20705. Joseph O. Kuti, Graduate Student, Department of Horticulture, University of Maryland, College Park 20704. Plant Dis. 68:524-526. Accepted for publication 20 January 1984. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1984. DOI: 10.1094/PD-68-524.

Growth rates of Mucor mucedo (ATCC 48559) and M. piriformis (ATCC 38314) were compared on mature green and ripe red tomato fruit and potato-dextrose agar (PDA) at temperatures from 0 to 40 C. M. mucedo grew on green and red tomatoes and PDA at temperatures from 5 to 30 C, with optimal growth at 25 C. M. piriformis grew on the above substrates at temperatures from 0 to 25 C, with an optimal growth temperature of 20 C. Both fungi grew faster on red than on green fruit; M. mucedo was a more aggressive pathogen than M. piriformis and was capable of completely decaying tomatoes within 2–3 days of inoculation. Of several fungicides tested, only guazatine showed measurable fungicidal action against the two fungi; it significantly reduced decay on ripe red fruit. This is the first reported incidence of M. mucedo as a postharvest pathogen of tomato.