Abstract
A plant factory with artificial lighting (PFAL) usually uses top lighting for cultivation. The light from the upper part of the canopy cannot penetrate the entire lettuce canopy, however, resulting in uneven vertical spatial light in the canopy, and accelerating the senescence of both the bottom and side leaves of the plant canopy. Therefore, in this study, the performance of lettuce in hydroponics was investigated upon supplemental side lighting with different spectral LEDs in a PFAL. A set of short-term side lighting treatments, including no side lamps (CK), red (R), blue (B), red + blue (RB), and red + blue + green (RGB) LED lamps (150 μmol·m−2·s−1, respectively), was employed for an additional 2 h per day after normal top lighting for 6 days before harvest. The results showed that the lettuce canopy was relatively loose and had a large crown size under side lighting compared with CK. Side lighting, irrespective of spectral qualities, significantly increased the fresh weight, and the R, B, RB, and RGB treatments increased the shoot fresh weight of lettuce plants by 34%, 19%, 31%, and 34%, and increased the fresh weight of leaf layer 2 by 50%, 17%, 44%, and 48%, respectively. The side lighting of different spectral qualities had a significant impact on the nutritional quality of the first row of lettuce at the edge of the top lighting illuminated area. Treatment B significantly promoted the chlorophyll content of leaf layer 3; the soluble sugar contents from leaf layer 1, 2, and 3; the starch contents in leaf layers 2 and 3; and the content of phenolics in the leaf layers 3; and significantly reduced the nitrate content in leaf layers 2 and 3. RGB significantly increased soluble sugar content by 91%, and the starch content in leaf layer 1, as well as the leaf chlorophyll and flavonoid content of leaf layer 3, while R had opposite effect completely. RB significantly increased the leaf chlorophyll content of leaf layer 3 and the nitrate content in leaf layer 1, but the overall effect was lower than that of RGB. In summary, side lighting of any type could effectively improve lettuce yield, solve the problem of inconsistent lettuce plant size caused by the edge effect of top lighting, and affect the nutritional quality of lettuce. B and RGB performed best. There was spatial response diversity of lettuce plants to side lighting spectral qualities.
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The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 20
Claim · model-written summary
Side lighting produced a looser lettuce canopy and larger crown than no side lamps.
- Taxon
- lettuce
Lactuca sativae0 - Treatment
- side lightinge0
- Outcome
- lettuce canopy was relatively loose and had a large crown sizee0
- Direction
- largee0
- Comparator
- CKe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The results showed that the lettuce canopy was relatively loose and had a large crown size under side lighting compared with CK.”
Claim · model-written summary
R side lighting increased lettuce shoot fresh weight by 34%.
- Taxon
- lettuceLactuca sativae0
- Treatment
- Re0
- Outcome
- shoot fresh weight of lettuce plantse0
- Direction
- increasede0
- Value
- 34%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the R, B, RB, and RGB treatments increased the shoot fresh weight of lettuce plants by 34%, 19%, 31%, and 34%, and increased the fresh weight of leaf layer 2 by 50%, 17%, 44%, and 48%, respectively.”
Claim · model-written summary
B side lighting increased lettuce shoot fresh weight by 19%.
- Taxon
- lettuceLactuca sativae0
- Treatment
- Be0
- Outcome
- shoot fresh weight of lettuce plantse0
- Direction
- increasede0
- Value
- 19%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the R, B, RB, and RGB treatments increased the shoot fresh weight of lettuce plants by 34%, 19%, 31%, and 34%, and increased the fresh weight of leaf layer 2 by 50%, 17%, 44%, and 48%, respectively.”
Claim · model-written summary
RB side lighting increased lettuce shoot fresh weight by 31%.
- Taxon
- lettuceLactuca sativae0
- Treatment
- RBe0
- Outcome
- shoot fresh weight of lettuce plantse0
- Direction
- increasede0
- Value
- 31%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the R, B, RB, and RGB treatments increased the shoot fresh weight of lettuce plants by 34%, 19%, 31%, and 34%, and increased the fresh weight of leaf layer 2 by 50%, 17%, 44%, and 48%, respectively.”
Claim · model-written summary
RGB side lighting increased lettuce shoot fresh weight by 34%.
- Taxon
- lettuceLactuca sativae0
- Treatment
- RGBe0
- Outcome
- shoot fresh weight of lettuce plantse0
- Direction
- increasede0
- Value
- 34%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the R, B, RB, and RGB treatments increased the shoot fresh weight of lettuce plants by 34%, 19%, 31%, and 34%, and increased the fresh weight of leaf layer 2 by 50%, 17%, 44%, and 48%, respectively.”
Claim · model-written summary
R side lighting increased lettuce leaf layer 2 fresh weight by 50%.
- Taxon
- lettuceLactuca sativae0
- Treatment
- Re0
- Outcome
- fresh weight of leaf layer 2e0
- Direction
- increasede0
- Value
- 50%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the R, B, RB, and RGB treatments increased the shoot fresh weight of lettuce plants by 34%, 19%, 31%, and 34%, and increased the fresh weight of leaf layer 2 by 50%, 17%, 44%, and 48%, respectively.”
Claim · model-written summary
B side lighting increased lettuce leaf layer 2 fresh weight by 17%.
- Taxon
- lettuceLactuca sativae0
- Treatment
- Be0
- Outcome
- fresh weight of leaf layer 2e0
- Direction
- increasede0
- Value
- 17%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the R, B, RB, and RGB treatments increased the shoot fresh weight of lettuce plants by 34%, 19%, 31%, and 34%, and increased the fresh weight of leaf layer 2 by 50%, 17%, 44%, and 48%, respectively.”
Claim · model-written summary
RB side lighting increased lettuce leaf layer 2 fresh weight by 44%.
- Taxon
- lettuceLactuca sativae0
- Treatment
- RBe0
- Outcome
- fresh weight of leaf layer 2e0
- Direction
- increasede0
- Value
- 44%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the R, B, RB, and RGB treatments increased the shoot fresh weight of lettuce plants by 34%, 19%, 31%, and 34%, and increased the fresh weight of leaf layer 2 by 50%, 17%, 44%, and 48%, respectively.”
Claim · model-written summary
RGB side lighting increased lettuce leaf layer 2 fresh weight by 48%.
- Taxon
- lettuceLactuca sativae0
- Treatment
- RGBe0
- Outcome
- fresh weight of leaf layer 2e0
- Direction
- increasede0
- Value
- 48%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the R, B, RB, and RGB treatments increased the shoot fresh weight of lettuce plants by 34%, 19%, 31%, and 34%, and increased the fresh weight of leaf layer 2 by 50%, 17%, 44%, and 48%, respectively.”
Claim · model-written summary
Blue side lighting promoted lettuce chlorophyll content of leaf layer 3.
Not reportedComparator
Verbatim
e0“Treatment B significantly promoted the chlorophyll content of leaf layer 3; the soluble sugar contents from leaf layer 1, 2, and 3; the starch contents in leaf layers 2 and 3; and the content of phenolics in the leaf layers 3; and significantly reduced the nitrate content in leaf layers 2 and 3.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
Claim · model-written summary
Blue side lighting promoted lettuce soluble sugar contents from leaf layer 1, 2, and 3.
- Taxon
- leafe0
- Treatment
- Treatment Be0
- Outcome
- soluble sugar contents from leaf layer 1, 2, and 3e0
- Direction
- promotede0
Not reportedComparator
Verbatim
e0“Treatment B significantly promoted the chlorophyll content of leaf layer 3; the soluble sugar contents from leaf layer 1, 2, and 3; the starch contents in leaf layers 2 and 3; and the content of phenolics in the leaf layers 3; and significantly reduced the nitrate content in leaf layers 2 and 3.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
Claim · model-written summary
Blue side lighting promoted lettuce starch contents in leaf layers 2 and 3.
Not reportedComparator
Verbatim
e0“Treatment B significantly promoted the chlorophyll content of leaf layer 3; the soluble sugar contents from leaf layer 1, 2, and 3; the starch contents in leaf layers 2 and 3; and the content of phenolics in the leaf layers 3; and significantly reduced the nitrate content in leaf layers 2 and 3.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
Claim · model-written summary
Blue side lighting promoted lettuce content of phenolics in the leaf layers 3.
- Taxon
- leafe0
- Treatment
- Treatment Be0
- Outcome
- content of phenolics in the leaf layers 3e0
- Direction
- promotede0
Not reportedComparator
Verbatim
e0“Treatment B significantly promoted the chlorophyll content of leaf layer 3; the soluble sugar contents from leaf layer 1, 2, and 3; the starch contents in leaf layers 2 and 3; and the content of phenolics in the leaf layers 3; and significantly reduced the nitrate content in leaf layers 2 and 3.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
Claim · model-written summary
Blue side lighting reduced lettuce nitrate content in leaf layers 2 and 3.
Not reportedComparator
Verbatim
e0“Treatment B significantly promoted the chlorophyll content of leaf layer 3; the soluble sugar contents from leaf layer 1, 2, and 3; the starch contents in leaf layers 2 and 3; and the content of phenolics in the leaf layers 3; and significantly reduced the nitrate content in leaf layers 2 and 3.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
Claim · model-written summary
RGB increased lettuce soluble sugar content by 91%.
- Taxon
- LettuceLactuca sativat0
- Treatment
- RGBe0
- Outcome
- soluble sugar contente0
- Direction
- increasede0
- Value
- 91%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“RGB significantly increased soluble sugar content by 91%, and the starch content in leaf layer 1, as well as the leaf chlorophyll and flavonoid content of leaf layer 3, while R had opposite effect completely.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
Claim · model-written summary
RGB increased lettuce starch content in leaf layer 1.
- Taxon
- LettuceLactuca sativat0
- Treatment
- RGBe0
- Outcome
- starch content in leaf layer 1e0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“RGB significantly increased soluble sugar content by 91%, and the starch content in leaf layer 1, as well as the leaf chlorophyll and flavonoid content of leaf layer 3, while R had opposite effect completely.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
Claim · model-written summary
RGB increased lettuce leaf chlorophyll and flavonoid content of leaf layer 3.
- Taxon
- LettuceLactuca sativat0
- Treatment
- RGBe0
- Outcome
- leaf chlorophyll and flavonoid content of leaf layer 3e0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“RGB significantly increased soluble sugar content by 91%, and the starch content in leaf layer 1, as well as the leaf chlorophyll and flavonoid content of leaf layer 3, while R had opposite effect completely.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
Claim · model-written summary
RB increased lettuce leaf layer 3 chlorophyll and leaf layer 1 nitrate content.
- Taxon
- LettuceLactuca sativat0
- Treatment
- RBe0
- Outcome
- leaf chlorophyll content of leaf layer 3 and the nitrate content in leaf layer 1e0
- Direction
- increasede0
- Comparator
- RGBe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“RB significantly increased the leaf chlorophyll content of leaf layer 3 and the nitrate content in leaf layer 1, but the overall effect was lower than that of RGB.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
Claim · model-written summary
Red lighting had the opposite effect to RGB on the reported lettuce quality measures.
- Taxon
- LettuceLactuca sativat0
- Treatment
- Re0
- Outcome
- opposite effecte0
- Comparator
- RGBe1
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“while R had opposite effect completely.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
e1“RGB significantly increased soluble sugar content by 91%”
Claim · model-written summary
Blue and RGB side lighting performed best for lettuce.
- Taxon
- LettuceLactuca sativat0
- Outcome
- performed beste0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“B and RGB performed best.”
t0“Lettuce (Lactuca sativa L. cv. “Yidali”)”
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