Estimates of broad-sense heritability for cut-flower vase longevity were 36 and 46 percent for a sample of Gerbera clones. Estimates of narrow-sense heritability for vase longevity were 0, 24 and 38 percent over 3 generations ofthe Davis Population. Response to selection for this character in this population is expected to be slow.

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The development of gerbera (Gerbera jamesonii H. Bolus ex. Hooker) as a floricultural crop is traced from its collection as a botanical novelty in South Africa to its establishment as a commercial crop in the 1930s. The origin of the cultivated germplasm, G. jamesonii and G. viridifolia (DC) Schultz- Bipontinus, is discussed, as well as breeding work that occurred in Europe and the United States. The contributions of the two species to the cultivated germplasm is unknown. Early breeding in Europe was conducted by RI. Lynch at the Cambridge Botanic Gardens in England, R. Adnet at La Rosarie in Antibes, France; and by C. Sprenger in Italy. In the United States, early work was done at estates in New Jersey by Herrington and Atkins, and by the commercial growers Jaenicke and the J.L. Childs' Seed Co. Establishing the cold hardiness of the crop for temperate climates was an early goal of horticulturists and breeders. Much of the cultivated germplasm can be traced to material that passed through Cambridge and Antibes.

Phenotypic (r p ), genetic (r g ), and environmental, (r e ) correlations were estimated for 38 flower traits in the Davis population of gerbera (Gerbera hybrida, Compositae). Fifty-two percent of r p and 38% of r g were statistically significant at P < 0.05. Significant negative r p were infrequent, but significant negative r g occurred in 10% of cases. There was a negative correlation between estimates of r g and r e , resulting in cases where r g was significant, but r p was not. Individual traits varied in their tendency to correlate phenotypically or genetically, and positively or negatively, with other traits. Traits within the same morphological category, such as disk florets or transitional florets, were more highly intercorrelated than were traits from different categories.

Gerbera hybrida, gerbera, inflorescence, floret, scape, heritability, components of variance, flower morphology. SUMMARYHeritability, repeatability, and components of variance were estimated for 68 morphological characters describing the inflorescence, scape, and florets of Gerbera hybrida. The heritability estimates were generally moderate to high for simple dimension characters and characters which were the mean of several measurements, low to moderate for ratio and composite characters, and low for enumeration characters and characters describing the intraplant variation of traits. The repeatability estimates were generally low for intraplant variation characters, moderate for simple ratio characters, and largest for composite and mean characters. For most of the characters, the variance among inflorescences from the same plant was the largest portion of the total phenotypic variance.