Photosynthetic Performance and Potency of <i>Cannabis sativa</i>L. Grown under LED and HPS Illumination

• 作者: Michael W. Jenkins Curtis B. Livesay
• 来源期刊: 农业科学(英文)
• 学科: 工学
• 关键词: CANNABIS Light-Emitting Diode LED High-Pressure Sodium HPS Carbon Assimilation Light Response Curve CANNABINOID THC POTENCY
• 年，卷（期）: 2021,（3）
• 页码范围: 293-304
• 页数: 12页
• 分类号: TN3

摘要

Light-emitting diodes (LEDs) can be used as an energy efficient alternative to high-pressure sodium (HPS), which have historically been the standard for supplemental lighting in cannabis cultivation. However, there is a lack of scientific understanding in the cannabis industry regarding plant physiology, which has resulted in the adoption of cannabis cultivation methods based on hearsay rather than scientific research. The goals of this study were to 1) compare LED lighting options that are commonly used in the cannabis industry and 2) compare the top performing LED light with an industry standard HPS light. Specifically, three LED lights were compared (California Light Works ((SolarSystem 1100), BIOS Lighting (Icarus Gi2), and Fluence Bioengineering (now Fluence by Osram) (SPYDR xPLUS)), based on light distribution, leaf temperature, and photosynthetic performance indices. The LED versus HPS comparison was based on light response curves measured at photosynthetic photon flux densities (PPFD) of (0, 100, 200, 300, 400, 500, 750, 1000, 1250, 1500, 1750 and 2000 μmol<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8729;</span></span>m^{<span style="white-space:nowrap;">&#8722;</span>2}<span style="white-space:nowrap;">&#8729;</span>s^{<span style="white-space:nowrap;">&#8722;</span>1}), carbon assimilation rates (<em>A</em>) μmol CO₂ m^{<span style="white-space:nowrap;">&#8722;</span>2}<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8729;</span></span>s^{<span style="white-space:nowrap;">&#8722;</span>1} using a LiCor-6800 and resulting cannabinoid potency (THCA). The SPYDR xPLUS-Fluence by Osram had the highest performing LED light used in the LED comparison. At the suggested distance from bulb to canopy in the HPS versus LED comparison (6 inches for LEDs and 4 ft for HPS), carbon assimilation rates displayed a 142% percent increase in plants grown under LED vs. HPS with average photon flux densities of 795 and 298 μmol<span s