Factors Affecting Flowering of Asclepias spp.

in HortScience
Authors: G. Nordwig1 and J.E. Erwin1
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  • 1 Dept. of Horticultural Science, Univ. of Minnesota, 1970 Folwell Ave., St. Paul, MN 55108

Asclepias sp. seed were germinated and placed under different photoperiod treatments at constant 15, 20, or 25 ± 2°C. Photoperiod treatments were 8 hr, 8 hr plus night interruption lighting (2200–0200 hr, 2 μmol·m–2·s–1 from incandescent lamps), day extension lighting 1700–2000 HR (100 μmol·m–2·s–1 from highpressure sodium lamps), or daylight plus continuous light (100 μmol·m–2·s–1 light from high-pressure sodium lamps) treatments. Treatments were terminated at anthesis or after 15 weeks. Variation in plant habit and flowering were documented. Also, temperature/photoperiod effects/interactions on plant development are discussed. Lastly, species were classified into appropriate photoperiodic groups and evaluated for potential use as new floriculture crops.