Spectral Filters Influence Transpirational Water Loss in Chrysanthemum

Transpiration rates of chrysanthemum [Dendranthema ×grandiflorum (Ramat.) Kitamura] plants grown under spectral filters were evaluated as part of an investigation on using light quality to regulate plant growth. The 6% CuSO4·5H2O spectral filter reduced photosynthetic photon flux density in red (R) and far red (FR) wavelengths and increased the R: FR and blue (B): R ratios (B = 400 to 500 nm; R = 600 to 700 nm; FR = 700 to 800 nm) of transmitted light relative to the water (control) filter. After 28 days, cumulative water use of plants grown under CuSO4 filters was ≈37% less than that of control plants. Transpiration rates were similar among plants grown under CuSO4 and control filters when expressed as leaf area, a result suggesting that the reduced cumulative water loss was a result of smaller plant size. Plants grown under CuSO4 filters had slightly lower (10%) stomatal density than control plants. Light transmitted through CuSO4 filters did not alter the size of individual stomata; however, total number of stomata and total stomatal pore area per plant was ≈50% less in plants grown under CuSO4 filters than in those grown under control filters due to less leaf area. The results suggest that altering light quality may help reduce water use and fertilizer demands while controlling growth during greenhouse production.

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EFFECTS OF SPECTRAL FILTERS ON GROWTH OF ROSA × HYBRIDA AND EXACUM AFFINE.

HortScience ◽

10.21273/hortsci.25.8.849a ◽

1990 ◽

Vol 25 (8) ◽

pp. 849a-849

Author(s):

Margaret J McMahon ◽

John W. Kelly

Keyword(s):

Light Quality ◽

Red Light ◽

Photosynthetic Photon Flux Density ◽

Photon Flux ◽

Photon Flux Density ◽

Textile Dye ◽

Light Spectrum ◽

Spectral Filters ◽

Leaf Chlorophyll ◽

Exacum Affine

The growth of Rosa × hybrida and Exacum affine under different spectral filters was evaluated. Three filters that altered light quality were developed. One, a red textile dye, filtered out much of the blue/green portion of the light spectrum but did not change far-red to red (FR/R) light ratio. Another, a blue textile dye, raised FR/R by filtering out a portion of red light. The third, a salt (copper sulfate) lowered FR/R by filtering out a greater portion of far-red than red light. Two controls were used that did not alter light quality. The filters were installed in specally built growth chambers. Photosynthetic Photon Flux Density (PPFD) was adjusted to equal values in each chamber. Plants of both species were significantly shorter and had higher leaf chlorophyll, when grown under the low FR/R filter.

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Light Quality Affects Water Use of Sweet Basil by Changing Its Stomatal Development

Agronomy ◽

10.3390/agronomy11020303 ◽

2021 ◽

Vol 11 (2) ◽

pp. 303

Author(s):

Sungeun Lim ◽

Jongyun Kim

Keyword(s):

Stomatal Conductance ◽

Blue Light ◽

Water Use ◽

Growth Parameters ◽

Stomatal Density ◽

Photon Flux ◽

Photon Flux Density ◽

Stomatal Development ◽

Sweet Basil ◽

Stomatal Responses

Different light qualities affect plant growth and physiological responses, including stomatal openings. However, most researchers have focused on stomatal responses to red and blue light only, and the direct measurement of evapotranspiration has not been examined. Therefore, we quantified the evapotranspiration of sweet basil under various red (R), green (G), and blue (B) combinations using light-emitting diodes (LEDs) and investigated its stomatal responses. Seedlings were subjected to five different spectral treatments for two weeks at a photosynthetic photon flux density of 200 µmol m−2 s−1. The ratios of the RGB light intensities were as follows: R 100% (R100), R:G = 75:25 (R75G25), R:B = 75:25 (R75B25), R:G:B = 60:20:20 (R60G20B20), and R:G:B = 31:42:27 (R31G42B27). During the experiment, the evapotranspiration of the plants was measured using load cells. Although there were no significant differences in growth parameters among the treatments, the photosynthetic rate and stomatal conductance were higher in plants grown under blue LEDs (R75B25, R60G20B20, and R31G42B27) than in the R100 treatment. The amount of water used was different among the treatments (663.5, 726.5, 728.7, 778.0, and 782.1 mL for the R100, R75G25, R60G20B20, R75B25, and R31G42B27 treatments, respectively). The stomatal density was correlated with the blue light intensity (p = 0.0024) and with the combined intensity of green and blue light (p = 0.0029); therefore, green light was considered to promote the stomatal development of plants together with blue light. Overall, different light qualities affected the water use of plants by regulating stomatal conductance, including changes in stomatal density.

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Effects of Light Quality on the Chlorophyll Degradation Pathway in Rice Seedling Leaves

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha44210555 ◽

2016 ◽

Vol 44 (2) ◽

pp. 393-398

Author(s):

Chang-Chang CHEN ◽

Kuan-Hung LIN ◽

Meng-Yuan HUANG ◽

Wen-Dar HUANG ◽

Chi-Ming YANG

Keyword(s):

Light Quality ◽

Protoporphyrin Ix ◽

Degradation Pathway ◽

Photosynthetic Photon Flux Density ◽

Rice Seedling ◽

Photon Flux ◽

Photon Flux Density ◽

Rice Seedlings ◽

Rice Varieties ◽

Enriched Environments

The objective of this study was to investigate the dynamics of chlorophyll (Chl), biosynthetic intermediates (protoporphyrin IX, magnesium protoporphyrin IX, and protochlorophyllide), degradation intermediates [chlorophyllide (Chlide), pheophytin (Phe), and pheophorbide (Pho)], and carotenoids (Car) in leaves of rice seedlings. Two rice varieties, 'Taichung Shen 10' ('TCS10') and 'IR1552', were grown under different light quality conditions controlled by light emitting diodes (LED). Lighting treatments for rice seedlings were included by red (R), blue (B), green (G), and red + blue (RB), with fluorescent lighting (FL) as the control and photosynthetic photon flux density being set at 105 µmol m-2 s-1. The results show that lower levels of Chl and Car in leaves were detected under G lighting, and light quality did not mediate porphyrins in biosynthetic pathways. Rice seedling leaves took Chl→Phe→Pho and Chl→Chlide→Pho as the major and minor degradation routes, respectively. Furthermore, higher Phe/Chlide ratios were observed under G and FL lighting conditions, indicating that green-enriched environments can up-regulate the minor degradation route in leaves.

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Response of Sonia roses to continuous daytime CO2 supplementation under controlled environment conditions

Australian Journal of Agricultural Research ◽

10.1071/ar9880863 ◽

1988 ◽

Vol 39 (5) ◽

pp. 863 ◽

Cited By ~ 3

Author(s):

M Zeroni ◽

J Gale

Keyword(s):

Leaf Area ◽

Photosynthetic Photon Flux Density ◽

Photon Flux ◽

Photon Flux Density ◽

Controlled Environment ◽

Flower Bud ◽

Flower Yield ◽

Co2 Concentrations ◽

Water Vapour Diffusion ◽

Flower Quality

Rose plants (Rosa hybrida cv. Sonia, Syn. Sweet Promise) were placed in growth chambers under conditions resembling winter in a controlled environment greenhouse in the desert: mild temperatures, high incident photosynthetic photon flux density (PPFD), high air humidity and 10.5 h daylenght. Concentrations of CO2 in the air were maintained throughout the day at 320, 600 or 1200 8l l-1 with approximately 350 8l l-1 at night. Plant growth (length, fresh and gry weight), development (breaks, blindness), flower yield and flower quality (flower bud diameter, fresh weight and cane length) indices were monitored throughout three consecutive flowering cycles. CO2 supplementation caused an increase in leaf resistance to water vapour diffusion, accompanied by a reduction in the rate of transpiration per unit leaf area, Total leaf area increased at higher CO2 concentrations. Water use per plant did not change. Plant water potentials increased with rising CO2 concentrations. Growth, development, flower yield and flower quality were greatly enahnced in the CO2-enriched atmosphere. The response of growth and development to CO2 supplementation tended to decrease slightly with time when calculated per branch, but increased when calculated per plant. Flower yield and qualtiy did not change with time. The highest CO2 treatment resulted in a sustained, approximately 50% increase in yield, and doubling of the above quality indices throughout the three growth cycles.

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The Impact of Carbon Dioxide Concentrations and Low to Adequate Photosynthetic Photon Flux Density on Growth, Physiology and Nutrient Use Efficiency of Juvenile Cacao Genotypes

Agronomy ◽

10.3390/agronomy11020397 ◽

2021 ◽

Vol 11 (2) ◽

pp. 397 ◽

Cited By ~ 1

Author(s):

Virupax C. Baligar ◽

Marshall K. Elson ◽

Alex-Alan F. Almeida ◽

Quintino R. de Araujo ◽

Dario Ahnert ◽

...

Keyword(s):

Carbon Dioxide ◽

Leaf Area ◽

Nutrient Use Efficiency ◽

Photosynthetic Photon Flux Density ◽

Photon Flux ◽

Photon Flux Density ◽

Photosynthetic Photon Flux ◽

Growth Physiology ◽

Nutrient Use ◽

Use Efficiency

Cacao (Theobroma cacao L.) was grown as an understory tree in agroforestry systems where it received inadequate to adequate levels of photosynthetic photon flux density (PPFD). As atmospheric carbon dioxide steadily increased, it was unclear what impact this would have on cacao growth and development at low PPFD. This research evaluated the effects of ambient and elevated levels carbon dioxide under inadequate to adequate levels of PPFD on growth, physiological and nutrient use efficiency traits of seven genetically contrasting juvenile cacao genotypes. Growth parameters (total and root dry weight, root length, stem height, leaf area, relative growth rate and net assimilation rates increased, and specific leaf area decreased significantly in response to increasing carbon dioxide and PPFD. Increasing carbon dioxide and PPFD levels significantly increased net photosynthesis and water-use efficiency traits but significantly reduced stomatal conductance and transpiration. With few exceptions, increasing carbon dioxide and PPFD reduced macro–micro nutrient concentrations but increased uptake, influx, transport and nutrient use efficiency in all cacao genotypes. Irrespective of levels of carbon dioxide and PPFD, intraspecific differences were observed for growth, physiology and nutrient use efficiency of cacao genotypes.

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Regulation of Chrysanthemum Growth by Spectral Filters

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.117.3.481 ◽

1992 ◽

Vol 117 (3) ◽

pp. 481-485 ◽

Cited By ~ 33

Author(s):

Nihal C. Rajapakse ◽

John W. Kelly

Keyword(s):

Light Quality ◽

Leaf Size ◽

Experimental Period ◽

Internode Length ◽

Photon Flux ◽

Average Height ◽

Dry Matter Accumulation ◽

Water Control ◽

Spectral Filters

The role of light quality and quantity in regulating growth of vegetative Dendranthema × grandiflorum (Ramat.) Kitamura was evaluated using CuSO4 solutions and water (control) as spectral filters. Copper sulfate filters increased the red (R): far-red (FR) and the blue (B): R ratios (R = 600 to 700 nm; FR = 700 to 800 nm; B = 400 to 500 urn) of transmitted light. Photosynthetic photon flux (PPF) under 4%, 8% and 16% CuSO4 filters was reduced 26%, 36%, and 47%, respectively, from natural irradiance in the greenhouse, which averaged ≈ 950 μmol·m-2·s-1. Control treatments were shaded with Saran plastic film to ensure equal PPF as the corresponding C uSO4 chamber. Average daily maxima and minima were 26 ± 3C and 16 ± 2C. At the end of the 4-week experimental period, average height and internode length of plants grown under CuSO4 filters were ≈ 40% and 34% shorter than those of plants grown under control filter. Reduction in plant height and internode length was apparent within 1 week after the beginning of treatment. Total leaf area (LA) was reduced by 32% and leaf size (LS) was reduced by 24% under CuSO4 filters. Specific leaf weight (SLW) was higher under CuSO4 filters than for the controls. Irradiance transmitted through CuSO4 filters reduced fresh and dry leaf weights by 30%. Fresh and dry stem weights of plants grown under CuSO4 filters were 60% lower than those of controls. Relative dry matter accumulation into leaves was increased in plants grown under CuSO4 filters while it was reduced in stems. A single application of GA3 before irradiation partially overcame the height reduction under CuSO4 filters, suggesting GA biosynthesis/action may be affected by light quality. Our results imply that alteration of light quality could be used to control chrysanthemum growth as an alternative method to conventional control by chemical growth regulators. Chemical names used: gibberellic acid (GA)

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Optimization of Photosynthetic Photon Flux Density and Light Quality for Increasing Radiation-Use Efficiency in Dwarf Tomato under LED Light at the Vegetative Growth Stage

Plants ◽

10.3390/plants11010121 ◽

2021 ◽

Vol 11 (1) ◽

pp. 121

Author(s):

Xinglin Ke ◽

Hideo Yoshida ◽

Shoko Hikosaka ◽

Eiji Goto

Keyword(s):

Vegetative Growth ◽

Growth Stage ◽

Light Quality ◽

Dry Mass ◽

Photosynthetic Photon Flux Density ◽

Photon Flux ◽

Photon Flux Density ◽

Photosynthetic Photon Flux ◽

Use Efficiency ◽

Radiation Use

Dwarf tomatoes are advantageous when cultivated in a plant factory with artificial light because they can grow well in a small volume. However, few studies have been reported on cultivation in a controlled environment for improving productivity. We performed two experiments to investigate the effects of photosynthetic photon flux density (PPFD; 300, 500, and 700 μmol m−2 s−1) with white light and light quality (white, R3B1 (red:blue = 3:1), and R9B1) with a PPFD of 300 μmol m−2 s−1 on plant growth and radiation-use efficiency (RUE) of a dwarf tomato cultivar (‘Micro-Tom’) at the vegetative growth stage. The results clearly demonstrated that higher PPFD leads to higher dry mass and lower specific leaf area, but it does not affect the stem length. Furthermore, high PPFD increased the photosynthetic rate (Pn) of individual leaves but decreased RUE. A higher blue light proportion inhibited dry mass production with the same intercepted light because the leaves under high blue light proportion had low Pn and photosynthetic light-use efficiency. In conclusion, 300 μmol m−2 s−1 PPFD and R9B1 are the recommended proper PPFD and light quality, respectively, for ‘Micro-Tom’ cultivation at the vegetative growth stage to increase the RUE.

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Influence of gibberellin A3 and ancymidol on sunflower leaf anatomy

Canadian Journal of Botany ◽

10.1139/b90-021 ◽

1990 ◽

Vol 68 (1) ◽

pp. 159-162 ◽

Cited By ~ 2

Author(s):

T. W. Starman ◽

J. W. Kelly ◽

H. B. Pemberton

Keyword(s):

Leaf Anatomy ◽

Leaf Surface ◽

Stomatal Density ◽

Unit Length ◽

Photosynthetic Photon Flux Density ◽

Photon Flux ◽

Photon Flux Density ◽

Photosynthetic Photon Flux ◽

Palisade Cell ◽

Leaf Surface Area

The plant growth retardant ancymidol (α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol), when sprayed at 132 mg/L of active ingredient, increased leaf thickness, palisade cell length, and number of cells per unit length, and decreased intercellular space percentage in developing Helianthus annuus L. (sunflower) cv. Mammoth Russian leaves when plants were grown under 400 or 1500 μmol∙s−1∙m−2 photosynthetic photon flux density. Foliar sprays of gibberellic acid at 10–40 mg/L reversed the effects of ancymidol on leaf anatomy. Stomatal density and total stomata per adaxial leaf surface area were increased by ancymidol sprays.

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THE EFFECT OF PHOTOSYNTHETIC PHOTON FLUX DENSITY ON CUCUMBER AND TOMATO TRANSPLANTS ASSIMILATIVE INDICES

Proceedings of the 7th International Scientific Conference Rural Development 2015 ◽

10.15544/rd.2015.030 ◽

2015 ◽

Author(s):

Aistė Bagdonavičienė ◽

Aušra Brazaitytė ◽

Julė Jankauskienė ◽

Pavelas Duchovskis

Keyword(s):

Solid State ◽

Leaf Area ◽

Weight Ratio ◽

Photosynthetic Photon Flux Density ◽

Photon Flux ◽

Photon Flux Density ◽

Photosynthetic Photon Flux ◽

Light Emitting ◽

Net Assimilation ◽

Positive Effect

The objective of our studies was to evaluate the assimilative indices of cucumber (‘Pasalimo F1’) and tomato (‘Marissa F1’) transplants, cultivated under various photosynthetic photon flux densities (PPFD) were provided by light-emitting diodes (LEDs). Experiment was performed in phytotron complex of Institute of Horticulture, LRCAF. A system of high-power, solid-state lighting modules with 92 % 638 nm (red) + 665 nm (red) + 731 nm (far red) and 8 % 447 nm (blue) was used in the experiments. The generated PPFD of each type of five solid-state modules was ~200 and ~400 μmol m-2 s-1. Our experiment revealed that increased net assimilation rate (NAR) depended on increased PPFD of cucumber and tomato hybrid. 400 μmol m-2 s-1 LED illumination had positive effect on relative growth rate (RGR). Cucumbers which were grown under 200 μmol m-2 s-1 had bigger leaf area ratio (LAR) and specific leaf area (SLA), their development has been bigger as compared to higher 400 μmol m-2 s-1 PPFD. High PPFD LED illumination had positive effect on leaf weight ratio (LWR), shoot root ratio (SRR) and tomato transplants development. These studies with various photosynthetic photon flux densities (PPFD) and LEDs light should be continued throughout plant vegetation.

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Gas Exchange Properties of Jointed Goatgrass (Aegilops cylindrica)

Weed Science ◽

10.1017/s0043174500060422 ◽

1987 ◽

Vol 35 (4) ◽

pp. 482-489 ◽

Cited By ~ 7

Author(s):

David R. Gealy

Keyword(s):

Dark Respiration ◽

Stomatal Density ◽

Photosynthetic Photon Flux Density ◽

Compensation Point ◽

Photon Flux ◽

Photon Flux Density ◽

Aegilops Cylindrica ◽

Jointed Goatgrass ◽

Diffusive Resistance ◽

Leaf Surfaces

Net (apparent) photosynthesis rate (Pn) of jointed goatgrass (Aegilops cylindricaHost # AEGCY) leaves in the greenhouse became light saturated at a photosynthetic photon flux density (PPFD) of about 1000 μE·m–1-2·s–1with a maximum Pn of 27 mg CO2·dm–2·h–1. Diffusive resistance to water vapor (rl) of adaxial leaf surfaces was 43% that of abaxial surfaces, in part, because stomatal density was 50% greater on adaxial leaf surfaces than on abaxial surfaces. Dark respiration rate (Rd) was 1.6 mg CO2·dm−2·h−1. Light compensation point (CPl) was 21 μE·m−2·s−1and CO2compensation point (CPc) was 32 ppmv. In the field, where light intensity and temperature were greater than in the greenhouse, leaves became light saturated for Pn at a higher intensity, and Rd and CPl were three times greater than in the greenhouse. Pn and Rd of spikes at anthesis were at least 30% less and 200% greater, respectively, than the values for leaves.

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