Abstract:
The cultivation of medical cannabis (Cannabis sativa L.) is expanding in controlled environments, driven by evolving governmental regulations for healthcare supply. Increasing inflorescence weight and plant specialized metabolite (PSM) concentrations is critical, alongside maintaining product consistency. Medical cannabis is grown under different spectra and photosynthetic photon flux densities (PPFD), the interaction between spectrum and PPFD on inflorescence weight and PSM attracts attention by both industrialists and scientists. Plants were grown in climate-controlled rooms without solar light, where four spectra were applied: two low-white spectra (7B-20G-73R/Narrow and 6B-19G-75R/2Peaks), and two high-white (15B-42G-43R/Narrow and 17B-40G-43R/Broad) spectra. The low-white spectra differed in red wavelength peaks (100% 660 nm, versus 50:50% of 640:660 nm), the high-white spectra differed in spectrum broadness. All four spectra were applied at 600 and 1200 μmol m-2 s-1. Irrespective of PPFD, white light with a dual red peak of 640 and 660 nm (6B-19G-75R/2Peaks) increased inflorescence weight, compared to white light with a single red peak of 660 nm (7B-20G-73R/Narrow) (tested at P = 0.1); this was associated with higher total plant dry matter production and a more open plant architecture, which likely enhanced light capture. At high PPFD, increasing white fraction and spectrum broadness (17B-40G-43R/Broad) produced similar inflorescence weights compared to white light with a dual red peak of 640 and 660 nm (6B-19G-75R/2Peaks). This was caused by an increase of both plant dry matter production and dry matter partitioning to the inflorescences. No spectrum or PPFD effects on cannabinoid concentrations were observed, although at high PPFD white light with a dual red peak of 640 and 660 nm (6B-19G-75R/2Peaks) increased terpenoid concentrations compared to the other spectra. At low PPFD, the combination of white light with 640 and 660 nm increased photosynthetic efficiency compared with white light with a single red peak of 660nm, indicating potential benefits in light use efficiency and promoting plant dry matter production. These results indicate that the interaction between spectrum and PPFD influences plant dry matter production. Dividing the light energy in the red waveband over both 640 and 660 nm equally shows potential in enhancing photosynthesis and plant dry matter production.
摘要:
医用大麻(CannabissativaL.)的种植在受控环境中不断扩大,由不断发展的政府医疗保健供应法规驱动。增加花序重量和植物专门代谢物(PSM)浓度是至关重要的,同时保持产品的一致性。医用大麻在不同的光谱和光合光子通量密度(PPFD)下生长,光谱与PPFD在花序重量和PSM上的相互作用引起了工业家和科学家的关注。植物生长在没有阳光的气候控制的房间里,其中应用了四个光谱:两个低白光谱(7B-20G-73R/Narrow和6B-19G-75R/2Peaks),和两个高白色(15B-42G-43R/Narrow和17B-40G-43R/Broad)光谱。低白色光谱在红色波长峰值(100%660nm,与640:660nm的50:50%相比),高白光谱的光谱宽度不同。所有四个光谱均在600和1200μmolm-2s-1下应用。不考虑PPFD,具有640和660nm的双红色峰(6B-19G-75R/2峰)的白光增加了花序重量,与单个红色峰为660nm(7B-20G-73R/Narrow)的白光相比(在P=0.1时测试);这与更高的植物总干物质产量和更开放的植物结构有关,这可能增强了光捕获。在高PPFD时,与具有640和660nm的双红色峰(6B-19G-75R/2Peaks)的白光相比,增加的白色分数和光谱宽度(17B-40G-43R/Broad)产生了相似的花序重量。这是由于植物干物质产量和向花序分配的干物质增加所致。未观察到光谱或PPFD对大麻素浓度的影响,尽管在高PPFD白光下具有640和660nm的双红色峰(6B-19G-75R/2峰),但与其他光谱相比,萜类化合物浓度增加。在低PPFD时,与具有660nm的单个红色峰的白光相比,具有640和660nm的白光的组合增加了光合效率,表明在光利用效率和促进植物干物质生产方面的潜在好处。这些结果表明,光谱和PPFD之间的相互作用会影响植物的干物质生产。在640和660nm上划分红色波段中的光能量同样显示出增强光合作用和植物干物质生产的潜力。