MOLECULAR MARKERS AND PROTEIN QUANTITIES AS GENETIC DESCRIPTORS IN MAIZE .2. PREDICTION OF PERFORMANCE OF HYBRIDS FOR FORAGE TRAITS

As it is related to the variability in genome expression, variability in protein quantities revealed by two-dimensional electrophoresis was proposed for describing phenotypic diversity. The objective of this st udy was to compare the predictive power of different genetic distances derived from molecular markers and from protein quantitative variatio ns in a diallel of 210 hybrids among 21 maize inbred lines (Zea mays L .) of various origin. The lines were characterized for: 1. 142 markers resulting from the analysis of enzyme, RFLP, and protein-structure po lymorphism; and 2. The variation in relative quantities of 190 protein s. The hybrids were evaluated for six forage traits in four environmen ts. Correlations between the genetic distances computed for 142 marker loci and hybrid performances were moderate to high in diallels using crosses between related lines. Genetic distances based on protein quan tities showed, in most cases, similar or lower correlations. Distance measures were not useful as predictors of hybrid performance for cross es between unrelated lines. Protein quantities were better for reveali ng specific genotypes.