The Quality and Quality Shifting of the Night Interruption Light Affect the Morphogenesis and Flowering in Floricultural Plants
The effects of the quality of night interruption (NI) on the morphogenesis and flowering were investigated in Petunia hybrida Hort. “Easy Wave Pink” (qualitative long-day plant), Pelargonium × hortorum L.H. Bailey “Ringo 2000 Violet” (day-neutral plant), and Dendranthema grandiflorum “gaya yellow” (qualitative short-day plant). Plants were grown in a closed-type plant factory under a light intensity of 180 μmol·m−2·s−1 PPFD (photosynthetic photon flux density) provided by white (W) light-emitting diodes (LEDs) under a condition of either long day (LD, 16 h light/8 h dark), short day (SD, 10 h light/14 h dark), or SD with 4 h NI. NI was provided by 10 ± 3 μmol·m−2·s−1 PPFD.
In the first experiment, NI was provided by blue (NI-B), green (NI-G), red (NI-R), far-red (NI-Fr), or white (NI-W) LEDs. The shoot length and plant height of the petunia and the geranium were the greatest in NI-Fr, while those of the chrysanthemum were the greatest in LD. In the petunia, flowering was observed in LD, NI-G, NI-Fr, and NI-W. Flowering of the geranium was not affected by the night interruption light (NIL) quality, and all plants flowered in all treatments. Flowering of the chrysanthemum was observed in SD, NI-B, and NI-Fr. These results suggest that the morphogenesis, flowering, and transcriptional factors of these plants were highly affected by the quality of the NIL, especially in the chrysanthemum. Furthermore, NI-R or NI-W was the most suitable in the NI strategy of controlling the morphogenesis and flowering of the long-day plants during SD seasons.
In the second experiment, the quality of the NIL was shifted from one to another after the first 2 h in sets of two qualities among B, R, Fr, and W. LD and SD were used as the control. Twelve SD treatments with shifting of the NIL quality by LEDs were as follows: from blue to red (NI-BR), from red to blue (NI-RB), from red to far-red (NI-RFr), from far-red to red (NI-FrR), from blue to far-red (NI-BFr), from far-red to blue (NI-FrB), from white to blue (NI-WB), from blue to white (NI-BW), from far-red to white (NI-FrW), from white to far-red (NI-WFr), from red to white (NI-RW), and from white to red (NI-WR). The plant height of the chrysanthemum was greater in NI treatments that consisted of Fr than that in other NI treatments, and it was the least in NI-WB among the NI treatments. Flowering of the chrysanthemum was observed in NI-RB, NI-FrR, NI-BFr, NI-FrB, NI-WB, NI-FrW, NI-WFr, NI-WR, and SD and was especially pronounced in NI-BFr and NI-FrB. The photoperiod affected both the morphogenesis and flowering in the chrysanthemum. While the first NIL did not affect either the morphogenesis or the flowering, the second NIL significantly affected both.
KeywordsDay-neutral plant Flowering control Light quality Long-day plant Morphogenesis Short-day plant
- Craig DS, Runkle ES (2012) Using LEDs to quantify the effect of the red to far-red ratio of night-interruption lighting on flowering of photoperiodic crops. Acta Hort (956):179–185Google Scholar
- Dougher TAO, Bugbee B (2004) Long-term blue light effects on the histology of lettuce and soybean leaves and stems. J Amer Soc Hort Sci 129:497–472Google Scholar
- Heins RD, Wilkins HF (1979) The influence of node number, light source, and time of irradiation during darkness on lateral branching and cutting production in ‘bright golden Anne’ chrysanthemum. J Amer Soc Hort Sci 104:265–270Google Scholar
- Huq E, Al-Sady B, Hudson M, Kim C, Apel K, Quail PH (2004) Phytochrome-interacting factor 1 is a critical bHLH regulator of chlorophyll biosynthesis. Sci Signaling 305:1937–1941Google Scholar
- Matsuda R, Ohashi-Kaneko K, Fujiwara K, Kurata K (2007) Analysis of the relationship between blue-light photon flux density and the photosynthetic properties of spinach (Spinacia oleracea L.) leaves with regard to the acclimation of photosynthesis to growth irradiance. Soil Sci Plant Nutr 53:459–465CrossRefGoogle Scholar
- Monte E, Tepperman JM, Al-Sady B, Kaczorowski KA, Alonso JM, Ecker JR, Li X, Zhang Y, Quail PH (2004) The phytochrome-interacting transcription factor, PIF3, acts early, selectively, and positively in light-induced chloroplast development. Proc Natl Acad Sci U S A 101:16091–16098CrossRefGoogle Scholar
- Purohit SS, Ranjan R (2002) Flowering. In: Purohit SS, Ranjan R (eds) Phytochrome and flowering. Agrobios, Jodhpur, pp 52–61Google Scholar
- Stack PA, Drummond FA, Stack LB (1998) Chrysanthemum flowering in a blue light-supplemented long day maintained for biocontrol of thrips. Hortscience 33:710–715Google Scholar
- Vince-Prue D, Canham AE (1983) Horticultural significance of photomorphogenesis. p. 518-544. In: Shropshire W, Mohr H (eds) Encyclopedia of plant physiology (NS). Springer-Verlag, BerlinGoogle Scholar