Photosynthetic Efficiency and Anatomical Structure of Pepper Leaf (Capsicum annuum L.) Transplants Grown under High-Pressure Sodium (HPS) and Light-Emitting Diode (LED) Supplementary Lighting Systems

The aim of this study was to evaluate the effects of various supplemental greenhouse lighting systems, i.e., high-pressure sodium lamps and mixtures of red and blue light-emitting diodes, on the photochemical efficiency, anatomical leaf structure, and growth of the two pepper cultivars. The intensity levels of the photosynthetically active radiation were the same for both light treatments. In this study, the relative chlorophyll content was measured. Additionally, certain parameters of chlorophyll a fluorescence were measured under ambient light or after dark adaptation. The obtained results showed that the application of light-emitting diodes (LEDs) as supplemental lighting positively affected the anatomical leaf characteristics and plant growth. The leaves of both pepper cultivars were thicker and had larger palisade parenchyma cells under LED supplemental lighting compared to leaves grown under high-pressure sodium (HPS) lamps. Moreover, the mesophyll cells of seedlings grown under LEDs contained more chloroplasts than those growing under HPS lighting. The chlorophyll a fluorescence measurements of pepper seedlings grown under LEDs showed significant increases in photosynthetic apparatus performance index (PI) values compared to plants grown under HPS lamps; however, the values for this index were higher in cv. ‘Aifos’ as compared to cv. ‘Palermo’. We recommend that supplemental lighting systems are applied with caution, as their performance appears to depend not only on the light spectrum but also on the cultivar.

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DAYTIME VARIATIONS OF CHLOROPHYLL A FLUORESCENCE IN PAU D'ALHO SEEDLINGS

Revista Árvore ◽

10.1590/0100-67622016000600007 ◽

2016 ◽

Vol 40 (6) ◽

pp. 1023-1030 ◽

Cited By ~ 2

Author(s):

Marcos Antonio Bacarin ◽

Emanuela Garbin Martinazzo ◽

Daniela Cassol ◽

Antelmo Ralph Falqueto ◽

Diolina Moura Silva

Keyword(s):

Chlorophyll A ◽

Chlorophyll A Fluorescence ◽

Photochemical Efficiency ◽

Photosynthetic Apparatus ◽

Photosynthetic Active Radiation ◽

High Radiation ◽

Active Radiation ◽

Fluorescence Measurements ◽

Subsequent Decrease ◽

Modulated Fluorescence

ABSTRACT Analysis of transient and modulated fluorescence of chlorophyll a were made at one-hour intervals during an eight-hour period starting at 07:30h aiming to study mechanisms of photoprotection against high radiation and temperature in Gallesia integrifolia plants. Seeds were germinated inside plastic pots containing soil as substrate. At 120 days after emergence, chlorophyll fluorescence measurements were performed using Handy-PEA and FMS2 fluorometers. During the course of a day, an increase and a subsequent decrease in temperature and in photosynthetic active radiation were observed until 12:30h. Changes in transient kinetic curves of chlorophyll a fluorescence were identified. This resulted in changes in JIP test parameters. An increase during the period of high radiation and temperature may be stressed in relation to variables related to dissipation flux and appearance of positive -K and -L bands. Considering the modulated fluorescence, high values of non-photochemical quenching coefficients associated with lower values of effective photochemical efficiency of the photosystem II (FV'/ FM') and current photochemical efficiency of PSII (φPSII) could be observed during early morning. This was probably the result of an inhibition of the biochemical phase of photosynthesis. It can be concluded that Gallesia integrifolia decrease its photochemical activity with the increase in the photosynthetic active radiation, demonstrating a photoinhibitory effect under high irradiance conditions, but without irreversible damages to the photosynthetic apparatus.

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Chlorophyll a fluorescence as an indicator of water stress in Calophyllum brasiliense

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha48111757 ◽

2020 ◽

Vol 48 (1) ◽

pp. 210-220 ◽

Cited By ~ 2

Author(s):

Lucas C. REIS ◽

Silvana P.Q. SCALON ◽

Daiane DRESCH ◽

Andressa Caroline FORESTI ◽

Cleberton C. SANTOS ◽

...

Keyword(s):

Water Deficit ◽

Chlorophyll A ◽

Chlorophyll A Fluorescence ◽

Stress Condition ◽

Water Status ◽

Photosynthetic Apparatus ◽

Stress Indicator ◽

Fluorescence Measurements ◽

Calophyllum Brasiliense ◽

And Function

The objective of this study was to evaluate chlorophyll a fluorescence as a stress indicator in Calophyllum brasiliense Cambess seedlings grown with different concentrations of abscisic acid (ABA) under intermittent water deficit condition: daily irrigation without ABA (I); daily irrigation + 10 μM ABA (I 10); daily irrigation + 100 μM ABA (I 100); suspension of daily irrigation without ABA (SI); suspension of daily irrigation + 10 μM ABA (SI 10) and suspension of daily irrigation + 100 μM ABA (SI 100). The intermittent water deficit reduces water status and impairs the photochemical apparatus functioning and seedling quality. The fluorescence measurements helped identify the stress condition of water deficit in the cultivation of C. brasiliense and the beneficial effect of the application of 10 μM of ABA in minimizing stress and facilitating the recovery of seedlings after re-irrigation, while maintaining the integrity and function of the photosynthetic apparatus.

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Evaluation the vigour of urban green lawn grown under long-term shade conditions by the use of chlorophyll fluorescence technique

Annals of Warsaw University of Life Sciences – SGGW Land Reclamation ◽

10.1515/sggw-2015-0025 ◽

2015 ◽

Vol 47 (3) ◽

pp. 203-210

Author(s):

Piotr Dąbrowski ◽

Bogumiła Pawluśkiewicz ◽

Aneta H. Baczewska ◽

Izabela Łukasik ◽

Vasilij Goltsev ◽

...

Keyword(s):

Light Intensity ◽

Chlorophyll A ◽

Chlorophyll A Fluorescence ◽

Urban Areas ◽

Plant Stress ◽

Photosynthetic Apparatus ◽

Light Conditions ◽

Fluorescence Measurements ◽

Significant Difference ◽

Lower Light

Abstract Unfavorable light conditions in urban areas are one of the most important cause of inappropriate grass communities condition. The possibility to detect the plant stress caused by shade is an important element in shaping the environment. The answer to following questions: what is the ability to detect the stress caused by shade in chosen lawn varieties of Perennial ryegrass by using the chlorophyll a fluorescence (O-J-I-P test) and which of tested varieties has the best properties to create grasslands in reduced light conditions is the aim of this work. Two-factor experimental micro-plot was conducted with three varieties and three different shadowing variants. Chlorophyll a fluorescence measurements were provided and were compared to leaf density. Our results explored significant difference between selected varieties in the terms of their photosynthetic apparatus adaption to light conditions. During May, all tested varieties were characterized by the rise of all fluorescence curve points under lower light intensity. The largest changes under shade conditions were noticed for the variety ‘Taya’. During next months a declining trend of photosynthetic efficiency for this variety was observed. On the basis of our results, we assume that each variety has unique threshold and needs of light intensity.

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Tomatoes Grown with Light-emitting Diodes or High-pressure Sodium Supplemental Lights have Similar Fruit-quality Attributes

HortScience ◽

10.21273/hortsci.50.10.1498 ◽

2015 ◽

Vol 50 (10) ◽

pp. 1498-1502 ◽

Cited By ~ 10

Author(s):

Michael P. Dzakovich ◽

Celina Gómez ◽

Cary A. Mitchell

Keyword(s):

High Pressure ◽

Fruit Quality ◽

Light Emitting Diodes ◽

Tomato Fruit ◽

Titratable Acidity ◽

Attractive Alternative ◽

Light Emitting ◽

Sensory Data ◽

Lighting Energy ◽

Supplemental Lighting

Light-emitting diodes (LEDs) are an attractive alternative to high-pressure sodium (HPS) lamps for plant growth because of their energy-saving potential. However, the effects of supplementing broad-waveband solar light with narrow-waveband LED light on the sensory attributes of greenhouse-grown tomatoes (Solanum lycopersicum) are largely unknown. Three separate studies investigating the effect of supplemental light quantity and quality on physicochemical and organoleptic properties of greenhouse-grown tomato fruit were conducted over 4- or 5-month intervals during 2012 and 2013. Tomato cultivars Success, Komeett, and Rebelski were grown hydroponically within a high-wire trellising system in a glass-glazed greenhouse. Chromacity, Brix, titratable acidity, electrical conductivity (EC), and pH measurements of fruit extracts indicated plant response differences between lighting treatments. In sensory panels, tasters ranked tomatoes for color, acidity, and sweetness using an objective scale, whereas color, aroma, texture, sweetness, acidity, aftertaste, and overall approval were ranked using hedonic scales. By collecting both physicochemical as well as sensory data, this study was able to determine whether statistically significant physicochemical parameters of tomato fruit also reflected consumer perception of fruit quality. Sensory panels indicated that statistically significant physicochemical differences were not noticeable to tasters and that tasters engaged in blind testing could not discern between tomatoes from different supplemental lighting treatments or unsupplemented controls. Growers interested in reducing supplemental lighting energy consumption by using intracanopy LED (IC-LED) supplemental lighting need not be concerned that the quality of their tomato fruits will be negatively affected by narrow-band supplemental radiation at the intensities and wavelengths used in this study.

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Comparison of Supplemental Lighting from High-pressure Sodium Lamps and Light-emitting Diodes during Bedding Plant Seedling Production

HortScience ◽

10.21273/hortsci.49.5.589 ◽

2014 ◽

Vol 49 (5) ◽

pp. 589-595 ◽

Cited By ~ 30

Author(s):

Wesley C. Randall ◽

Roberto G. Lopez

Keyword(s):

High Pressure ◽

Light Emitting Diodes ◽

Dry Mass ◽

Operating Life ◽

High Quality ◽

Light Emitting ◽

Northern Latitudes ◽

Bedding Plant ◽

Supplemental Lighting ◽

Plant Seedlings

Annual bedding plant seedlings or plugs are considered high quality when they are compact, fully rooted transplants with a large stem caliper and high root dry mass. Greenhouses in northern latitudes rely on supplemental lighting (SL) from high-pressure sodium lamps (HPS) during winter months to achieve high-quality, finished plugs. Light-emitting diodes (LEDs) offer higher energy efficiencies, a long operating life, and precise waveband specificity that can eliminate wavebands not considered useful. Seedlings of Antirrhinum, Catharanthus, Celosia, Impatiens, Pelargonium, Petunia, Tagetes, Salvia, and Viola were grown at 21 °C under a 16-hour photoperiod of ambient solar light and SL of 100 μmol·m−2·s–1 from either HPS lamps or LED arrays with varying proportions (%) of red:blue light (100:0, 85:15, or 70:30). Height of Catharanthus, Celosia, Impatiens, Petunia, Tagetes, Salvia, and Viola was 31%, 29%, 31%, 55%, 20%, 9%, and 35% shorter, respectively, for seedlings grown under the 85:15 red:blue LEDs compared with those grown under HPS lamps. Additionally, stem caliper of Antirrhinum, Pelargonium, and Tagetes was 16%, 8%, and 13% larger, respectively, for seedlings grown under the 85:15 red:blue LEDs compared with seedlings grown under HPS lamps. The quality index (QI), a quantitative measurement of quality, was similar for Antirrhinum, Catharanthus, Impatiens, Pelargonium, and Tagetes grown under LEDs and HPS lamps. However, it was significantly higher for Petunia, Salvia, and Viola under 85:15, 70:30, and 100:0 red:blue LEDs than under HPS lamps, respectively. These results indicate that seedling quality for the majority of the species tested under SL from LEDs providing both red and blue light was similar or higher than those grown under HPS lamps.

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Multiple effects of chromate on the photosynthetic apparatus of Spirodela polyrhiza as probed by OJIP chlorophyll a fluorescence measurements

Environmental Pollution ◽

10.1016/s0269-7491(01)00091-4 ◽

2001 ◽

Vol 115 (1) ◽

pp. 49-64 ◽

Cited By ~ 222

Author(s):

K.-J Appenroth ◽

J Stöckel ◽

A Srivastava ◽

R.J Strasser

Keyword(s):

Chlorophyll A ◽

Chlorophyll A Fluorescence ◽

Photosynthetic Apparatus ◽

Spirodela Polyrhiza ◽

Fluorescence Measurements

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Cuttings of Impatiens, Pelargonium, and Petunia Propagated under Light-emitting Diodes and High-pressure Sodium Lamps Have Comparable Growth, Morphology, Gas Exchange, and Post-transplant Performance

HortScience ◽

10.21273/hortsci.48.4.428 ◽

2013 ◽

Vol 48 (4) ◽

pp. 428-434 ◽

Cited By ~ 26

Author(s):

Christopher J. Currey ◽

Roberto G. Lopez

Keyword(s):

High Pressure ◽

Gas Exchange ◽

Light Emitting Diodes ◽

Dry Mass ◽

Stem Length ◽

Light Sources ◽

Growth Morphology ◽

Light Emitting ◽

Supplemental Lighting ◽

The Impact

Increasing photosynthetic daily light integral (DLI) by supplementing with high-pressure sodium (HPS) lamps during propagation has been shown to enhance photosynthesis and biomass accumulation of cuttings. The development of high-intensity light-emitting diodes (LEDs) is a promising technology with potential as a greenhouse supplemental lighting source. Our objective was to quantify the impact of narrow spectra supplemental lighting from LEDs on growth, morphology, and gas exchange of cuttings compared with traditional HPS supplemental lighting. Cuttings of Impatiens hawkeri W. Bull ‘Celebrette Frost’, Pelargonium ×hortorum L.H. Bailey ‘Designer Bright Red’, and Petunia ×hybrida Vilm. ‘Suncatcher Midnight Blue’ were received from a commercial propagator and propagated in a glass-glazed greenhouse at 23 °C air and substrate temperature set points. After callusing (≈5 mol·m−2·d−1 for 7 days), cuttings were placed under 70 μmol·m−2·s−1 delivered from HPS lamps or LED arrays with varying proportions (%) of red:blue light (100:0, 85:15, or 70:30). After 14 days under supplemental lighting treatments, growth, morphology, and gas exchange of rooted cuttings were measured. There were no significant differences among Impatiens and Pelargonium cuttings grown under different supplemental light sources. However, compared with cuttings propagated under HPS lamps, stem length of Petunia cuttings grown under 100:0 red:blue LEDs was 11% shorter, whereas leaf dry mass, root dry mass, root mass ratios, and root:shoot ratio of cuttings grown under 70:30 red:blue LEDs were 15%, 36%, 17%, and 24% higher, respectively. Supplemental light source had minimal impact on plants after transplant. Our data suggest that LEDs are suitable replacements for HPS lamps as supplemental light sources during cutting propagation.

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