Title: | Facing energy limitations - approaches to increase basil (Ocimum basilicum L.) growth and quality by different increasing light intensities emitted by a broadband LED light spectrum (400-780 nm) |
Author(s): | Tabbert JM; Schulz H; Krahmer A; Riewe D; |
Address: | "Julius Kuhn Institute - Federal Research Centre for Cultivated Plants, Institute for Ecological Chemistry, Plant Analysis and Stored Product Protection, Berlin, Germany. Institute of Pharmacy, Freie Universitat Berlin, Berlin, Germany. Consulting & Project Management for Medicinal and Aromatic Plants, Stahnsdorf, Germany" |
DOI: | 10.3389/fpls.2022.1055352 |
ISSN/ISBN: | 1664-462X (Print) 1664-462X (Electronic) 1664-462X (Linking) |
Abstract: | "Based on the current trend towards broad-bandwidth LED light spectra for basil productions in multi-tiered controlled-environment horticulture, a recently developed white broad-bandwidth LED light spectrum (400-780 nm) including far-red wavelengths with elevated red and blue light fractions was employed to cultivate basil. Four Ocimum basilicum L. cultivars (cv. Anise, cv. Cinnamon, cv. Dark Opal and cv. Thai Magic) were exposed to two different rising light intensity conditions (I(Low) and I(High)). In dependence of the individual cultivar-specific plant height increase over time, basil cultivars were exposed to light intensities increasing from ~ 100 to ~ 200 micromol m(-2) s(-1) under I(Low), and from 200 to 400 micromol m(-2) s(-1) under I(High) (due to the exponential light intensity increases with decreasing proximity to the LED light fixtures). Within the first experiment, basils' morphological developments, biomass yields and time to marketability under both light conditions were investigated and the energy consumptions were determined to calculate the basils' light use efficiencies. In detail, cultivar-dependent differences in plant height, leaf and branch pair developments over time are described. In comparison to the I(Low) light conditions, I(High) resulted in accelerated developments and greater yields of all basil cultivars and expedited their marketability by 3-5 days. However, exposure to light intensities above ~ 300 micromol m(-2) s(-1) induced light avoidance responses in the green-leafed basil cultivars cv. Anise, cv. Cinnamon and cv. Thai Magic. In contrast, I(Low) resulted in consumer-preferred visual qualities and greater biomass efficiencies of the green-leafed basil cultivars and are discussed as a result of their ability to adapt well to low light conditions. Contrarily to the green-leafed cultivars, purple-leafed cv. Dark Opal developed insufficiently under I(Low), but remained light-tolerant under I(High), which is related to its high anthocyanin contents. In a second experiment, cultivars' volatile organic compound (VOC) contents and compositions over time were investigated. While VOC contents per gram of leaf dry matter gradually decreased in purple-leafed cv. Dark Opal between seedling stage to marketability, their contents gradually increased in the green cultivars. Regardless of the light treatment applied, cultivar-specific VOC compositions changed tremendously in a developmental stage-dependent manner" |
Keywords: | energy use efficiency (EUE) essential oil light-emitting diode (LED) morphology volatile organic compound (VOC); |
Notes: | "PubMed-not-MEDLINETabbert, Jenny Manuela Schulz, Hartwig Krahmer, Andrea Riewe, David eng Switzerland 2022/12/13 Front Plant Sci. 2022 Nov 24; 13:1055352. doi: 10.3389/fpls.2022.1055352. eCollection 2022" |