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

1988 ◽  
Vol 39 (5) ◽  
pp. 863 ◽  
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.

scholarly journals 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 ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 397 ◽  
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.

scholarly journals Pre-Harvest UV-B Radiation and Photosynthetic Photon Flux Density Interactively Affect Plant Photosynthesis, Growth, and Secondary Metabolites Accumulation in Basil (Ocimum Basilicum) Plants

Agronomy ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 434 ◽  
Author(s):  
Haijie Dou ◽  
Genhua Niu ◽  
Mengmeng Gu
Keyword(s):  
Phenolic Compounds ◽  
Flux Density ◽  
Photosynthetic Photon Flux Density ◽  
Ocimum Basilicum ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Yield Reduction ◽  
Controlled Environment ◽  
Photosynthetic Photon Flux ◽  
Plant Yield

Phenolic compounds in basil (Ocimum basilicum) plants grown under a controlled environment are reduced due to the absence of ultraviolet (UV) radiation and low photosynthetic photon flux density (PPFD). To characterize the optimal UV-B radiation dose and PPFD for enhancing the synthesis of phenolic compounds in basil plants without yield reduction, green and purple basil plants grown at two PPFDs, 160 and 224 μmol·m−2·s−1, were treated with five UV-B radiation doses including control, 1 h·d−1 for 2 days, 2 h·d−1 for 2 days, 1 h·d−1 for 5 days, and 2 h·d−1 for 5 days. Supplemental UV-B radiation suppressed plant growth and resulted in reduced plant yield, while high PPFD increased plant yield. Shoot fresh weight in green and purple basil plants was 12%–51% and 6%–44% lower, respectively, after UV-B treatments compared to control. Concentrations of anthocyanin, phenolics, and flavonoids in green basil leaves increased under all UV-B treatments by 9%–18%, 28%–126%, and 80%–169%, respectively, and the increase was greater under low PPFD compared to high PPFD. In purple basil plants, concentrations of phenolics and flavonoids increased after 2 h·d−1 UV-B treatments. Among all treatments, 1 h·d−1 for 2 days UV-B radiation under PPFD of 224 μmol·m−2·s−1 was the optimal condition for green basil production under a controlled environment.

scholarly journals Cannabis lighting: Decreasing blue photon fraction increases yield but efficacy is more important for cost effective production of cannabinoids

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248988
Author(s):  
F. Mitchell Westmoreland ◽  
Paul Kusuma ◽  
Bruce Bugbee
Keyword(s):  
Cost Effective ◽  
Photosynthetic Photon Flux Density ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Spectral Quality ◽  
Yield And Quality ◽  
Flower Yield ◽  
Red Led ◽  
Photon Conversion ◽  
Potential Interactions

LED technology facilitates a range of spectral quality, which can be used to optimize photosynthesis, plant shape and secondary metabolism. We conducted three studies to investigate the effect of blue photon fraction on yield and quality of medical hemp. Conditions were varied among studies to evaluate potential interactions with environment, but all environmental conditions other than the blue photon fraction were maintained constant among the five-chambers in each study. The photosynthetic photon flux density (PPFD, 400 to 700 nm) was rigorously maintained at the set point among treatments in each study by raising the fixtures. The lowest fraction of blue photons was 4% from HPS, and increased to 9.8, 10.4, 16, and 20% from LEDs. There was a consistent, linear, 12% decrease in yield in each study as the fraction of blue photons increased from 4 to 20%. Dry flower yield ranged from 500 to 750 g m-2. This resulted in a photon conversion efficacy of 0.22 to 0.36 grams dry flower mass yield per mole of photons. Yield was higher at a PPFD of 900 than at 750 μmol m-2 s-1. There was no effect of spectral quality on CBD or THC concentration. CBD and THC were 8% and 0.3% at harvest in trials one and two, and 12% and 0.5% in trial three. The CBD/THC ratio was about 25 to 1 in all treatments and studies. The efficacy of the fixtures ranged from 1.7 (HPS) to 2.5 μmol per joule (white+red LED). Yield under the white+red LED fixture (10.4% blue) was 4.6% lower than the HPS on a per unit area basis, but was 27% higher on a per dollar of electricity basis. These findings suggest that fixture efficacy and initial cost of the fixture are more important for return on investment than spectral distribution at high photon flux.

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

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.

scholarly journals How Supplementary or Night-Interrupting Low-Intensity Blue Light Affects the Flower Induction in Chrysanthemum, A Qualitative Short-Day Plant

Plants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1694
Author(s):  
Yoo Gyeong Park ◽  
Byoung Ryong Jeong
Keyword(s):  
Blue Light ◽  
Photosynthetic Photon Flux Density ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Control Group ◽  
Flower Bud ◽  
Low Intensity ◽  
Short Day ◽  
Flower Bud Formation ◽  
Cryptochrome 1

This research examined the effects of the supplementary or night-interrupting (NI) blue (B) light supplied at a low intensity on the flowering, gene expression, and morphogenesis of chrysanthemum, a qualitative short-day plant. White (W) light-emitting diodes (LEDs) were used to provide light with a photosynthetic photon flux density (PPFD) of 180 μmol·m−2·s−1 during the photoperiod to grow the plants in a plant factory. The control group was constructed with plants that were exposed to a 10-h short day (SD10) treatment without any blue light. The B light in this research was used for 4 h to either (1) extend the photoperiod for plants at the end of a 9-h short day (SD) treatment as the sole light source (SD9 + 4B), (2) provide night interruption (NI) to plants in the 13-h long-day (LD) treatment (LD13 + NI − 4B), (3) provide NI to plants in the 10-h SD treatment (SD10 + NI − 4B), or (4) supplement the W LEDs at the end of a 13-h LD treatment (LD13 + 4B). Blue LEDs were used to provide the supplementary/NI light at 10 μmol·m−2·s−1 PPFD. The LD13 + NI − 4B treatment resulted in the greatest plant height, followed by LD13 + 4B. Plants in all treatments flowered. It is noteworthy that despite the fact that chrysanthemum is a qualitative SD plant, chrysanthemum plants flowered when grown in the LD13 + 4B and LD13 + NI − 4B treatments. Plants grown in the LD13 + 4B had the greatest number of flowers. Plants grown in the LD13 + 4B treatment had the highest expression levels of the cryptochrome 1, phytochrome A, and phytochrome B genes. The results of this study indicate that a 4-h supplementation of B light during the photoperiod increases flower bud formation and promotes flowering, and presents a possibility as an alternative method to using blackout curtains in LD seasons to practically induce flowering. The B light application methods to induce flowering in SD plants requires further research.

Effect of Light, Watering Frequency, and Chlorsulfuron on Canada Thistle (Cirsium arvense)

Weed Science ◽  
1991 ◽  
Vol 39 (4) ◽  
pp. 590-594 ◽  
Author(s):  
Robert L. Zimdahl ◽  
Jingzhu Lin ◽  
Armando A. Dall'Armellina
Keyword(s):  
Leaf Area ◽  
Field Experiments ◽  
Dry Weight ◽  
Photosynthetic Photon Flux Density ◽  
Water Levels ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Canada Thistle ◽  
Root Dry Weight ◽  
Effect Of Light

Greenhouse and field experiments were conducted to determine effects of light, water, and chlorsulfuron on growth of Canada thistle. In the greenhouse, shoot and root dry weight, leaf area, and number of inflorescences decreased as light and water levels decreased. In the field, shoot and root dry weight, leaf area, and number of Canada thistle inflorescences were positively correlated with light intensity from 1832 to 30 μmol m−2s−1photosynthetic photon flux density (PPFD). The greatest effect of light was on inflorescence production which was eliminated at 30 μmol m−2s−1(PPFD). The combined effect of water stress and chlorsulfuron decreased root and shoot growth but did not eliminate it.

Effects of Density and Species Proportion on Competition between Spurred Anoda (Anoda cristata) and Velvetleaf (Abutilon theophrasti)

Weed Science ◽  
1990 ◽  
Vol 38 (4-5) ◽  
pp. 351-357 ◽  
Author(s):  
David T. Patterson
Keyword(s):  
Leaf Area ◽  
Mixed Culture ◽  
Photosynthetic Photon Flux Density ◽  
Photon Flux ◽  
Shoot Biomass ◽  
Photon Flux Density ◽  
Regression Equations ◽  
Shoot Weight ◽  
Biomass Plant ◽  
The Impact

Spurred anoda and velvetleaf were grown for 40 days in controlled-environment chambers in monocultures at densities of 2, 4, 8, and 12 plants per 20-cm-diam pot and in mixed culture with all combinations of 2, 4, 8, and 12 plants of each species per pot. The day/night temperature was 29/23 C, and the photosynthetic photon flux density (PPFD) was 1000 μE m–2s–1. Shoot dry weights and leaf areas of the two species were similar when they were grown in monoculture. However, in mixed culture spurred anoda exceeded velvetleaf in leaf area/plant and shoot weight/plant in 15 out of 16 treatments. Multiple linear regression equations relating shoot biomass/plant to the density of both species in mixed culture were calculated. Comparison of competition coefficients from these equations indicated that the competitive impact of a single spurred anoda plant was equivalent to the impact of 2.5 velvetleaf plants. In mixed culture, spurred anoda always contributed a greater proportion of the total shoot weight and total leaf area per pot than would be predicted from its proportion of the total plant population. These results indicate spurred anoda is competitively superior to velvetleaf.

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