Relationship between Phloem Fiber and Trailing Habit, and Independent Inheritance of Growth Habit and Flower Form in Periwinkle
Journal
Journal of the American Society for Horticultural Science
Journal Volume
143
Journal Issue
1
Pages
67-71
Date Issued
2018
Author(s)
Abstract
Stem anatomy and modulus of elasticity (MOE) were compared between upright and trailing cultivars of periwinkle [ Catharanthus roseus (G.) Don.]. The inheritance of growth habit and flower form was also studied. Internode cross sections revealed that phloem fiber was distributed at the inner cortex in upright cultivars but not in trailing cultivars. Except the youngest internode, the upright ‘Vitesse Pink’ had the highest MOE throughout the 1st–13th internodes above the cotyledon. The more trailing ‘Cora Cascade Strawberry’ had consistently lower MOE than a less trailing ‘Cora Cascade Polka Dot’. All F 1 plants between upright and trailing cultivars were upright, and the F 2 generation derived from self-pollinating F 1 fit a 3 upright : 1 trailing segregation ratio. All F 1 plants between upright/double-flower and trailing/single-flower exhibited upright and single-flowers, whereas plants in the F 2 generation fitted a 9 upright/single-flower : 3 trailing/single-flower : 3 upright/double-flower : 1 trailing/double-flower ratio. New double-flowered periwinkle selections with trailing growth habit were successfully developed from the F 2 population.
Type
journal article