Abstract
The influence of solar UV‐A and UV‐B radiation at Beltsville, MD, USA, on growth of Lactuca sativa L. (cv. New Red Fire lettuce) was examined during early summer of 1996 and 1997. Plants were grown from seed in plastic window boxes covered with Llumar to exclude UV‐A and UV‐B, polyester to exclude UV‐B, or tefzel (1996) or teflon (1997) to transmit UV‐A and UV‐B radiation. After 31–34 days, plants grown in the absence of solar UV‐B radiation (polyester) had 63 and 57% greater fresh weight and dry weight of tops, respectively, and 57, 72 and 47% greater dry weight of leaves, stems and roots, respectively, as compared to those grown under ambient UV‐B (tefzel or teflon). Plants protected from UV‐A radiation as well (Llumar) showed an additional 43 and 35% increase, respectively, in fresh and dry weight of tops and a 33 and 33% increase, respectively, in dry weight of leaves and stems, but no difference in root biomass over those grown under polyester. Excluding ambient UV‐B (polyester) significantly reduced the UV absorbance of leaf extracts at 270, 300 and 330 nm (presumptive flavonoids) and the concentration of anthocyanins at 550 nm as compared to those of leaf extracts from plants grown under ambient UV‐A and UV‐B. Additional removal of ambient UV‐A (Llumar) reduced the concentration of anthocyanins, but had no further effect on UV absorbance at 270, 300 or 330 nm. These findings provide evidence that UV‐B radiation is more important than UV‐A radiation for flavonoid induction in this red‐pigmented lettuce cultivar. Although previous workers have obtained decreases in lettuce yield under enhanced UV‐B, this is the first evidence for inhibitory effects of solar UV‐A and UV‐B radiation on lettuce growth.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
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 15
Claim · model-written summary
Excluding solar UV-B increased fresh weight of tops by 63% compared with ambient UV-B.
- Taxon
- Lactuca sativa
Lactuca sativae6 - Material
- New Red Fire lettucee6
- Organ / stage
- topse0
- Treatment
- absence of solar UV‐B radiatione0
- Outcome
- fresh weighte0
- Direction
- greatere0
- Value
- 63e0
- Comparator
- ambient UV‐B (tefzel or teflon)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“plants grown in the absence of solar UV‐B radiation (polyester) had 63 and 57% greater fresh weight and dry weight of tops, respectively, and 57, 72 and 47% greater dry weight of leaves, stems and roots, respectively, as compared to those grown under ambient UV‐B (tefzel or teflon)”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Excluding solar UV-B increased dry weight of tops by 57% compared with ambient UV-B.
- Taxon
- Lactuca sativaLactuca sativae6
- Material
- New Red Fire lettucee6
- Organ / stage
- topse0
- Treatment
- absence of solar UV‐B radiatione0
- Outcome
- dry weighte0
- Direction
- greatere0
- Value
- 57%e0
- Comparator
- ambient UV‐B (tefzel or teflon)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“plants grown in the absence of solar UV‐B radiation (polyester) had 63 and 57% greater fresh weight and dry weight of tops, respectively, and 57, 72 and 47% greater dry weight of leaves, stems and roots, respectively, as compared to those grown under ambient UV‐B (tefzel or teflon)”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Excluding solar UV-B increased dry weight of leaves by 57% compared with ambient UV-B.
- Taxon
- Lactuca sativaLactuca sativae6
- Material
- New Red Fire lettucee6
- Organ / stage
- leavese0
- Treatment
- absence of solar UV‐B radiatione0
- Outcome
- dry weighte0
- Direction
- greatere0
- Value
- 57e0
- Comparator
- ambient UV‐B (tefzel or teflon)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“plants grown in the absence of solar UV‐B radiation (polyester) had 63 and 57% greater fresh weight and dry weight of tops, respectively, and 57, 72 and 47% greater dry weight of leaves, stems and roots, respectively, as compared to those grown under ambient UV‐B (tefzel or teflon)”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Excluding solar UV-B increased dry weight of stems by 72% compared with ambient UV-B.
- Taxon
- Lactuca sativaLactuca sativae6
- Material
- New Red Fire lettucee6
- Organ / stage
- stemse0
- Treatment
- absence of solar UV‐B radiatione0
- Outcome
- dry weighte0
- Direction
- greatere0
- Value
- 72e0
- Comparator
- ambient UV‐B (tefzel or teflon)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“plants grown in the absence of solar UV‐B radiation (polyester) had 63 and 57% greater fresh weight and dry weight of tops, respectively, and 57, 72 and 47% greater dry weight of leaves, stems and roots, respectively, as compared to those grown under ambient UV‐B (tefzel or teflon)”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Excluding solar UV-B increased dry weight of roots by 47% compared with ambient UV-B.
- Taxon
- Lactuca sativaLactuca sativae6
- Material
- New Red Fire lettucee6
- Organ / stage
- rootse0
- Treatment
- absence of solar UV‐B radiatione0
- Outcome
- dry weighte0
- Direction
- greatere0
- Value
- 47e0
- Comparator
- ambient UV‐B (tefzel or teflon)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“plants grown in the absence of solar UV‐B radiation (polyester) had 63 and 57% greater fresh weight and dry weight of tops, respectively, and 57, 72 and 47% greater dry weight of leaves, stems and roots, respectively, as compared to those grown under ambient UV‐B (tefzel or teflon)”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Additional exclusion of UV-A increased fresh weight of tops by 43% compared with plants under polyester.
- Taxon
- Lactuca sativaLactuca sativae6
- Material
- New Red Fire lettucee6
- Organ / stage
- topse1
- Treatment
- protected from UV‐A radiatione1
- Outcome
- freshe1
- Direction
- increasee1
- Value
- 43e1
- Comparator
- polyestere1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Plants protected from UV‐A radiation as well (Llumar) showed an additional 43 and 35% increase, respectively, in fresh and dry weight of tops and a 33 and 33% increase, respectively, in dry weight of leaves and stems, but no difference in root biomass over those grown under polyester”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Additional exclusion of UV-A increased dry weight of tops by 35% compared with plants under polyester.
- Taxon
- Lactuca sativaLactuca sativae6
- Material
- New Red Fire lettucee6
- Organ / stage
- topse1
- Treatment
- protected from UV‐A radiatione1
- Outcome
- dry weighte1
- Direction
- increasee1
- Value
- 35e1
- Comparator
- polyestere1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Plants protected from UV‐A radiation as well (Llumar) showed an additional 43 and 35% increase, respectively, in fresh and dry weight of tops and a 33 and 33% increase, respectively, in dry weight of leaves and stems, but no difference in root biomass over those grown under polyester”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Additional exclusion of UV-A increased dry weight of leaves by 33% compared with plants under polyester.
- Taxon
- Lactuca sativaLactuca sativae6
- Material
- New Red Fire lettucee6
- Organ / stage
- leavese1
- Treatment
- protected from UV‐A radiatione1
- Outcome
- dry weighte1
- Direction
- increasee1
- Value
- 33e1
- Comparator
- polyestere1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Plants protected from UV‐A radiation as well (Llumar) showed an additional 43 and 35% increase, respectively, in fresh and dry weight of tops and a 33 and 33% increase, respectively, in dry weight of leaves and stems, but no difference in root biomass over those grown under polyester”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Additional exclusion of UV-A increased dry weight of stems by 33% compared with plants under polyester.
- Taxon
- Lactuca sativaLactuca sativae6
- Material
- New Red Fire lettucee6
- Organ / stage
- stemse1
- Treatment
- protected from UV‐A radiatione1
- Outcome
- dry weighte1
- Direction
- increasee1
- Value
- 33e1
- Comparator
- polyestere1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Plants protected from UV‐A radiation as well (Llumar) showed an additional 43 and 35% increase, respectively, in fresh and dry weight of tops and a 33 and 33% increase, respectively, in dry weight of leaves and stems, but no difference in root biomass over those grown under polyester”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Additional exclusion of UV-A had no difference in root biomass compared with plants under polyester.
- Taxon
- Lactuca sativaLactuca sativae6
- Material
- New Red Fire lettucee6
- Organ / stage
- roote1
- Treatment
- protected from UV‐A radiatione1
- Outcome
- root biomasse1
- Direction
- no differencee1
- Comparator
- polyestere1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Plants protected from UV‐A radiation as well (Llumar) showed an additional 43 and 35% increase, respectively, in fresh and dry weight of tops and a 33 and 33% increase, respectively, in dry weight of leaves and stems, but no difference in root biomass over those grown under polyester”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Excluding ambient UV-B significantly reduced UV absorbance of leaf extracts at 270, 300 and 330 nm.
- Taxon
- Lactuca sativaLactuca sativae6
- Organ / stage
- leafe2
- Treatment
- Excluding ambient UV‐B (polyester)e2
- Outcome
- UV absorbance of leaf extractse2
- Direction
- reducede2
- Qualifier
- 270, 300 and 330 nme2
- Comparator
- plants grown under ambient UV‐A and UV‐Be2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“Excluding ambient UV‐B (polyester) significantly reduced the UV absorbance of leaf extracts at 270, 300 and 330 nm (presumptive flavonoids) and the concentration of anthocyanins at 550 nm as compared to those of leaf extracts from plants grown under ambient UV‐A and UV‐B”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Excluding ambient UV-B significantly reduced anthocyanin concentration at 550 nm.
- Taxon
- Lactuca sativaLactuca sativae6
- Organ / stage
- leaf extractse2
- Treatment
- Excluding ambient UV‐B (polyester)e2
- Outcome
- concentration of anthocyaninse2
- Direction
- reducede2
- Qualifier
- 550 nme2
- Comparator
- plants grown under ambient UV‐A and UV‐Be2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“Excluding ambient UV‐B (polyester) significantly reduced the UV absorbance of leaf extracts at 270, 300 and 330 nm (presumptive flavonoids) and the concentration of anthocyanins at 550 nm as compared to those of leaf extracts from plants grown under ambient UV‐A and UV‐B”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Additional removal of ambient UV-A reduced anthocyanin concentration.
- Taxon
- Lactuca sativaLactuca sativae6
- Treatment
- Additional removal of ambient UV‐A (Llumar)e3
- Outcome
- concentration of anthocyaninse3
- Direction
- reducede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e3“Additional removal of ambient UV‐A (Llumar) reduced the concentration of anthocyanins, but had no further effect on UV absorbance at 270, 300 or 330 nm”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
Additional removal of ambient UV-A had no further effect on UV absorbance at 270, 300 or 330 nm.
- Taxon
- Lactuca sativaLactuca sativae6
- Treatment
- Additional removal of ambient UV‐A (Llumar)e3
- Outcome
- UV absorbancee3
- Direction
- no further effecte3
- Qualifier
- 270, 300 or 330 nme3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e3“Additional removal of ambient UV‐A (Llumar) reduced the concentration of anthocyanins, but had no further effect on UV absorbance at 270, 300 or 330 nm”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
Claim · model-written summary
UV-B radiation is more important than UV-A radiation for flavonoid induction in this lettuce cultivar.
- Taxon
- lettuceLactuca sativae4
- Treatment
- UV‐B radiatione4
- Outcome
- flavonoid inductione4
- Direction
- more importante4
- Comparator
- UV‐A radiatione4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e4“These findings provide evidence that UV‐B radiation is more important than UV‐A radiation for flavonoid induction in this red‐pigmented lettuce cultivar”
e6“growth of Lactuca sativa L. (cv. New Red Fire lettuce)”
The same questions in other papers
uv · growth · Lactuca sativa (garden lettuce)Results differ
14 papers in the same direction as this paper · 20 in the opposite direction
- negative
- no effect
- negative
31 papers more in this group
See all 35 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.