Effect of high-pressure sodium lighting on greenhouse production of vegetative cuttings for ten species of annual floricultural crops

• Published in: Acta horticulturae no. 580; pp. 221 - 228
• Main Authors: Donnelly, C.S, Fisher, P.R
• Format: Journal Article
• Language: English
• Published: International Society for Horticultural Science 01.01.2002
• Subjects: Aloysia citrodora; Argyranthemum; cultivars; cutting; floriculture crops; greenhouse production; Heliotropium arborescens; hybrids; Impatiens; lamps; Lantana; Osteospermum; Petunia; photosynthetically active radiation; Scaevola; sodium; supplementary lighting; Verbena; New Guinea
• ISSN: 0567-7572
• DOI: 10.17660/ActaHortic.2002.580.29

The objective was to quantify the effect of supplemental lighting on cutting production for herbaceous annual cultivars. Stock plants of four cultivars (Heliotropium arborescens 'Atlantis', Petunia 'Supertunia Sun Snow', Scaevola aemula 'New Wonder', and Verbena 'Tapien Soft Pink') received ambient light (average 156 μmol m-2 s-1 PAR during the photoperiod), or ambient light plus either 42 or 70 μmol m-2 s-1 from high-pressure sodium (HPS) lamps for 11 hours. In a second experiment, the same four species plus six other cultivars were grown under ambient light (199 μmol m-2 s-1) or ambient plus 48 μmol m-2 s-1 HPS. Effect of HPS on cutting production varied greatly between species. Growth of Heliotropium was not significantly affected by light level in either experiment. Petunia 'Supertunia Sun Snow', Scaevola, and Verbena increased cutting numbers by 14, 51, and 12% at 42 μmol m-2 s-1 HPS and by 23%, 73%, and 22% at 70 μmol m-2 s-1 HPS in the first experiment. In the second experiment, Petunia ‘Supertunia Sun Snow', Scaevola aemula 'New Wonder', Aloysia triphylla (lemon verbena), and Osteospermum 'Lemon Symphony' had a positive cutting production response to HPS (17-45% increase), whereas cutting numbers of other species (Argyranthemum 'Summer Melody', Impatiens New Guinea hybrid 'Pedro', Lantana 'Patriot Firewagon', Petunia 'Supertunia Blue Wren', and Verbena) were not significantly affected by HPS. In both experiments, cutting quality (length, stem caliper, fresh mass and dry mass) was not significantly affected by light level.