Light Intensity and Light Quality from Sole-source Light-emitting Diodes Impact Phytochemical Concentrations within Brassica Microgreens
Light Intensity and Light Quality from Sole-source Light-emitting Diodes Impact Phytochemical Concentrations within Brassica Microgreens
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DOI：
10.21273/jashs03830-16
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发表时间：
2017-01-01
影响因子：
1.9
通讯作者：
Kopsell, Dean A.
中科院分区：
文献类型：
--
作者：
Craver, Joshua K.;Gerovac, Joshua R.;Kopsell, Dean A.
使用单源（SS）发光二极管（LED）的多层垂直生产系统可以替代更传统的微绿色生产方法。使用LED的一个显著好处是能够选择对植物形态和促进健康的植物化学物质的合成具有有益影响的光质量。因此，本研究的目的是量化不同光质和强度的SS LED对芸苔（Brassica sp.）微绿具体而言，植物化学测量包括1）总花青素，2）总类胡萝卜素和单独类胡萝卜素，3）总叶绿素和单独叶绿素，以及4）总酚类。甘蓝（Brassica oleracea var. gongylodes）、芥菜（芥菜“石榴石巨人”）和水菜（芜菁变种）。日本）在放置在步入式生长室中的多层架上的水培托盘系统中生长。在红光：蓝光87：13（R-87：B-13）、红光：远红光：蓝光84：7：9（R-84：FR 7：B-9）或红光：绿色：蓝光74：18：8（R-74：G（18）：B-8）的光比（百分比）下，SS LED阵列在400至800 nm的总光子通量分别为105、210或315 mmol.m（-2）.s（-1）的条件下持续16小时，每日光积分（DLI）分别为6、12或18 mol.m（-2）.d（-1）。使用分光光度法和高效液相色谱法（HPLC）收集植物化学测量值。无论光的质量，总类胡萝卜素显着降低下增加光照强度的水菜和芥菜。此外，光质对总叶绿素含量也有影响，在R-87：B-13光比下，甘蓝和芥菜的总叶绿素含量分别高于R-84：FR 7：B-9和R-74：G（18）：B-8。对于球茎甘蓝，随着光照强度的增加，花青素的总浓度比那些生长在较低的光照强度。此外，在315 mmol.m（-2）.s（-1）的光照强度下，与R-74：G（18）：B-8的光照比相比，R-87：B-13或R-84：FR 7：B-9的光照比显著提高了蓝甘蓝的花青素含量。光质对球茎甘蓝的总酚含量也有影响，在105 mmol·m（-2）·s（-1）光强下，光比R（84）：FR 7：B-9的总酚含量显著高于R-74：G（18）：B-8。而光照强度对大头菜总酚含量的影响不显著。从这项研究的结果提供了进一步的洞察光的质量和强度的选择，使用SS LED，以实现优选的植物化学成分的芸苔属微绿。
Multilayer vertical production systems using sole-source (SS) light-emitting diodes (LEDs) can be an alternative to more traditional methods of microgreens production. One significant benefit of using LEDs is the ability to select light qualities that have beneficial impacts on plant morphology and the synthesis of health-promoting phytochemicals. Therefore, the objective of this study was to quantify the impacts of SS LEDs of different light qualities and intensities on the phytochemical content of brassica (Brassica sp.) microgreens. Specifically, phytochemical measurements included 1) total anthocyanins, 2) total and individual carotenoids, 3) total and individual chlorophylls, and 4) total phenolics. Kohlrabi (Brassica oleracea var. gongylodes), mustard (Brassica juncea 'Garnet Giant'), and mizuna (Brassica rapa var. japonica) were grown in hydroponic tray systems placed on multilayer shelves in a walk-in growth chamber. A daily light integral (DLI) of 6, 12, or 18 mol.m(-2).d(-1) was achieved from SS LED arrays with light ratios (percent) of red:blue 87:13 (R-87:B-13), red:far-red:blue 84:7:9 (R-84:FR7:B-9), or red:green:blue 74:18:8 (R-74:G(18):B-8) with a total photon flux from 400 to 800 nm of 105, 210, or 315 mmol.m(-2).s(-1) for 16 hours, respectively. Phytochemical measurements were collected using spectrophotometry and high-performance liquid chromatography (HPLC). Regardless of light quality, total carotenoids were significantly lower under increasing light intensities for mizuna and mustard microgreens. In addition, light quality affected total integrated chlorophyll with higher values observed under the light ratio of R-87:B-13 compared with R-84:FR7:B-9 and R-74:G(18):B-8 for kohlrabi and mustard microgreens, respectively. For kohlrabi, with increasing light intensities, the total concentration of anthocyanins was greater compared with those grown under lower light intensities. In addition, for kohlrabi, the light ratios of R-87:B-13 or R-84:FR7:B-9 produced significantly higher anthocyanin concentrations compared with the light ratio of R-74:G(18):B-8 under a light intensity of 315 mmol.m(-2).s(-1). Light quality also influenced the total phenolic concentration of kohlrabimicrogreens, with significantly greater levels for the light ratio ofR(84):FR7:B-9 compared with R-74:G(18):B-8 under a light intensity of 105 mmol.m(-2).s(-1). However, the impact of light intensity on total phenolic concentration of kohlrabi was not significant. The results from this study provide further insight into the selection of light qualities and intensities using SS LEDs to achieve preferred phytochemical content of brassica microgreens.