Morphology and Inheritance of Double Floweredness in Catharanthus roseus

Abstract

<jats:p>A double-flowered periwinkle [<jats:italic>Catharanthus roseus</jats:italic> (L.) G. Don.] mutant TYV1 was identified and the morphology and inheritance of the double-flowered phenotype was studied. TYV1 has an outer salverform whorl of petals and an additional inner funnel-shaped whorl of petals originating from the apex of the corolla. The apex of corolla tube forms a narrow opening. There are hairs under the opening at the apex. The stigma in this mutant is set below the anthers. The overlap between the top end of the pistil and bottom ends of anthers in TYV1 flowers at 1 to 2 days after anthesis is 0.56 ± 0.01 mm. TYV1 could be used as either the male or female parent in crossing. Self-pollinated TYV1 produced all double-flowered progeny compared with self-pollinated single-flowered cultivars Little Pinkie and Titan Burgundy, which produced all single-flowered progeny. F<jats:sub>1</jats:sub> plants between TYV1 and ‘Little Pinkie’ or ‘Titan Burgundy’ were all single. Three F<jats:sub>2</jats:sub> populations segregated into 3 single: 1 double ratio. Backcrossing F<jats:sub>1</jats:sub> to seed parents also indicated that a double-flowered form was controlled by a recessive allele. A single dominant gene expressed in the homozygous or heterozygous state resulted in the single-flowered phenotype. All the young seedlings of self-pollinated TYV1 and double-flowered progeny had distorted leaves before the sixth pair of leaves emerged.</jats:p>

Early Selection of Double Flowers Based on Cotyledon Shape in Cut Stock (Matthiola incana L.) Flowers

“…Also, this commercial cut flower is one of the best options for greenhouse owners during the winter due to its high resistance against cold (Eid et al, 2009). Flower doubleness seems to be the main feature for breeding research in the ornamental species such as stocks, roses (Dubois et al, 2010), Catharanthus (Chen et al, 2012), and carnations (Yagi et al, 2014). Two different forms of stock flower have been characterized: single and double-flowered.…”