Supplementary Light with Increased Blue Fraction Accelerates Emergence and Improves Development of the Inflorescence in Aechmea, Guzmania and Vriesea

Abstract

In protected cultivation, increasing the light level via supplementary lighting (SL) is critical to improve external quality, especially in periods with low light availability. Despite wide applications, the effect of light quality remains understated. In this study, the effect of SL quality and nutrient solution electrical conductivity (EC) on growth and flowering of three bromeliad species was investigated. Treatments included solar light, and this supplemented with R90B10 [90% red (R) and 10% blue (B)], R80B20 (80% R and 20% B), and R70B30 (70% R and 30% B). These were combined with an EC of 1 and 2 dS m-l. Irrespective of the light treatment, the higher EC promoted growth, inflorescence emergence, and development in Aechmea fasciata (Lindl.) Baker, whereas adverse effects were noted in Guzmania and Vriesea. The higher EC-induced negative effect in Guzmania and Vriesea was slightly alleviated by SL. With few notable exceptions, SL exerted limited effects on photosynthetic functionality. Depending on the species, SL improved external quality traits. In all species, SL increased root and inflorescence weight and stimulated biomass allocation to generative organs. It also accelerated inflorescence emergence and promoted inflorescence development. In this way, the time to commercial development stage was considerably shortened. These effects were more prominent at R80B20 and R70B30. Under those conditions, for instance, inflorescence emergence occurred 3–5 weeks earlier than in the control, depending on the species. In conclusion, SL with increased B proportion leads to shorter production period owing to faster emergence and improved development of the inflorescence and is recommended for commercial use.

A Polysaccharide-Based Integrated Nutrient Management System Enhances the Antioxidant Properties in Origanum dictamnus (Lamiaceae), a Valuable Local Endemic Plant of Crete

“…Plant species conservation necessitates the introduction of commercially valuable taxa into agricultural settings and their sustainable utilization to alleviate the over-harvesting pressure on wild populations [52]. In response to this need, cultivation practices and farming operations ought to be developed and established, predominantly employing an optimized fertilization program.…”

“…Leaf coloration depends on the fertilization regime, and affects both photosynthetic capacity and visually perceived quality [52]. In this study, it was assessed by three different methods as follows:…”

Growth, Biomass Partitioning, and Photosynthetic Performance of Chrysanthemum Cuttings in Response to Different Light Spectra

“…In contrast, R light partitioned more biomass into the root and caused the highest root dry weight to be gained when the biomass of both monochromatic light recipes is compared to the biomass of plants exposed to other light qualities ( Figure 1 and Table 1 ). The alteration of biomass partitioning to different plant organs as a consequence of plant growth in different lighting environments has been reported in diverse plant species such as chrysanthemum [ 30 ], saffron [ 28 , 31 ], bromeliads [ 32 ], and lettuce [ 23 , 33 ].…”

“…Contrary to the findings obtained in the present study, it has been reported that R light is an inducer of shoot growth. In contrast, B light usually restricts biomass allocation to the above-ground parts (especially into the leaves, while it promotes biomass partitioning into the generative organs) [ 32 ]. However, Hernández and Kubota (2016) reported that monochromatic B light caused a dramatic increase in the length of cucumber seedlings compared to other spectra, which follows our results [ 34 ].…”

Plants exposed to titanium dioxide nanoparticles acquired contrasting photosynthetic and morphological strategies depending on the growing light intensity: a case study in radish

“…Following removal of the substrate from the tuber via gentle washing, tuber volume was measured by employing a volume-displacement technique 62 , 63 . Tubers were suspended in a cylinder filled with water, and tuber volume was then determined by measuring the volume of displaced water.…”