Evaluation of Combining Ability, Heterosis, and Genetic Variance for Fruit Quality Characteristics in Bush Muskmelon

Abstract

Abstract A 6-parent diallel was established in 1981 at Excelsior, Minn, and at Santa Paula, Calif, to analyze combining ability and heterosis for fruit quality of traits in bush muskmelon ( Cucumis melo L.). GCA variance exceeded SCA variance for all traits. Minnesota breeding lines were superior in GCA for most interior quality traits, but inferior to Florida and California lines in exterior quality. Correlations between the performance of parents and the average of their hybrids were consistently positive, and often significant. Favorable heterosis over the midparent was shown for soluble solids, net density, and net rope, and, to a lesser extent, for flesh amount, rind thickness, cavity amount, and cavity dryness. A 3 × 10 design II at Excelsior showed estimates of additive variance exceeding those of dominance variance for all traits except fruit weight, shape index, and vein tract. The large estimates of additive variance provided for moderately high (40–70%) estimates of heritability for most traits.