GENETIC PARAMETER ESTIMATES FOR GREENHOUSE TRAITS OF SLASH PINE ARTIFICIALLY INOCULATED WITH FUSIFORM RUST FUNGUS

Six-week-old greenhouse-grown seedlings of 100 open-pollinated slash pine families were artificially inoculated with fusiform rust fungus in three testing periods at the USDA Forest Service Resistance Screening Center. Six months after inoculation, seedlings were scored for symptoms of rust infection. Genetic parameters (heritabilities, genetic correlations and family x test interactions) were estimated for 16 traits. Eleven traits appear highly promising for inclusion into a selection index to predict breeding values for rust resistance in the field. For these 11 traits, family x test interaction was not important, family heritabilities were high (> 0.78), and differences among the four groups of families were minor for family variance, variance of family means, and heritability estimates. The other five traits had measurable amounts of family x test interaction and lower heritability estimates (< 0.70).