Comparison of Inheritance of Resistance to Tomato Anthracnose Caused by Two Colletotrichum spp.. Anita N. Miller, Graduate Student, Department of Horticulture, University of Maryland, College Park 20742. Timothy J NG, Associate Professor, Department of Horticulture, University of Maryland, College Park 20742, and Thomas H. Barksdale, Research Plant Pathologist, Vegetable Laboratory, U.S. Department of Agriculture, Agricultural Research Service, Beltsville, MD 20705.. Plant Dis. 68:875-877. Accepted for publication 11 April 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-68-875.

Inheritance in tomato of resistance to anthracnose caused by Colletotrichum coccodes and C. dematium was compared using a six-parent diallel in 1982. The parents, one set of F₁ hybrids, and five reciprocal crosses were grown at the USDA Beltsville Agricultural Research Center. Reciprocal effects were not present in either set of inoculations of the two pathogens for the five crosses studied. Mean squares for general combining ability accounted for most of the genetic variability in both sets of inoculations. Mean squares for specific combining ability were only significant for the inoculations involving C. dematium. According to the analysis of variance and covariance of the parental arrays, partial dominance appeared to be in the direction of susceptibility. Narrow-sense heritabilities were 78% for C. coccodes and 64% for C. dematium. The correlation coefficient between inoculations with C. coccodes and C. dematium was 0.87.

Keyword(s): Lycopersicon esculentum.