scholarly journals Effect of Light Intensity on Efficiency of Carbon Dioxide and Nitrogen Reduction in Pisum sativum L.

1977 ◽  
Vol 60 (6) ◽  
pp. 868-871 ◽  
Author(s):  
Gabor J. Bethlenfalvay ◽  
Donald A. Phillips
Keyword(s):  
Carbon Dioxide ◽  
Light Intensity ◽  
Pisum Sativum ◽  
Nitrogen Reduction ◽  
Pisum Sativum L ◽  
Effect Of Light

scholarly journals On the effect of carbon dioxide on geotropic curvature of the roots of Pisum sativum L

1905 ◽  
Vol 76 (510) ◽  
pp. 351-358 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Pisum Sativum ◽  
Root Growth ◽  
Partial Pressure ◽  
Vicia Sativa ◽  
Main Root ◽  
Cent Carbon Dioxide ◽  
Aerial Parts ◽  
Pisum Sativum L ◽  
Partial Pressures

Many physiologists have shown that, in general, carbon dioxide exercises a narcotic or toxic influence on vegetable protoplasm, temporarily or permanently affecting its activity, according to the partial pressure under which the gas acts. De Saussure (1), as long ago as 1804, stated that, in an atmosphere containing 8 per cent. Carbon dioxide, the growth of peas was less than in air; Böhm (2), in 1873, found that roots of Phaseolus multiflorus , after 17 days’ exposure, exhibited successively less elongation in partial pressures of 2, 5, 10, and 14 per cent. Carbon dioxide respectively, the temperature ranging between 17° and 19° C.; in each percentage named the growth was progressively less than in normal air. Montemartini (3), in 1892, working with roots of Pisum , found 7 per cent. and upwards to depress growthactivity. Chapin (4), in 1902, found the growth of roots of Pisum sativum and Vicia sativa to be diminished by 5 per cent., and arrested by 25 to 30 per cent. and upwards. Growth of the stem in the same plants was diminished by 15 per cent., and completely inhibited by 22 to 25 per cent. Experiments conducted by one of us, in conjunction with Professor Farmer, have proved that seedling peas may be kept in an atmosphere containing 20 per cent. carbon dioxide for 14 days without losing the power of renewed growth when placed in air. It is interesting to note that, in many of these plants, the plumule was destroyed, although the main root continued to grow, growth being carried on by shoots arising in the axils of the cotyledons. Brown and Escombe (5) grew plants in increased partial pressures of carbon dioxide. The anatomy of these plants was investigated by Farmer and Chandler (6), who found the growth of the aërial parts to be diminished, while root-growth was apparently unaltered. Ewart (7) observed that carbon dioxide stops protoplasmic steaming, but he does not state the percentage employed in his experiments.

QUALITY, YIELD, AND SEED WEIGHT OF GREEN FIELD PEAS UNDER CONDITIONS OF APPLIED SHADE

1981 ◽  
Vol 61 (2) ◽  
pp. 213-217 ◽  
Author(s):  
G. H. GUBBELS
Keyword(s):  
Light Intensity ◽  
Pisum Sativum ◽  
Protein Content ◽  
Seed Weight ◽  
Field Studies ◽  
Field Pea ◽  
Green Color ◽  
Pisum Sativum L ◽  
Field Peas ◽  
Very High

Field studies were conducted in 1973 and 1974 to evaluate the effects of light intensity on the quality and yield of the green field pea (Pisum sativum L.) ’Triumph’. The treatments included a control with no shading (80 klx) and shading with one (31 klx) or two (9 klx) layers of screen material for a 3-wk period before maturity. Shading resulted in a significant decrease in seed weight and yield and a significant increase in protein content of the seed. The effect of shading on viscosity of the cooked samples was quadratic, implying that viscosity only decreased at very high levels of shading. Shading also tended to reduce loss of green color in the seed cotyledons.

RELATIONSHIPS BETWEEN CARBON DIOXIDE EXCHANGE RATE, PHOTOSYNTHETIC AREA AND BIOMASS IN PEA

1986 ◽  
Vol 66 (3) ◽  
pp. 465-472 ◽  
Author(s):  
S. L. A. HOBBS
Keyword(s):  
Carbon Dioxide ◽  
Exchange Rate ◽  
Pisum Sativum ◽  
Chlorophyll Content ◽  
Substantial Reduction ◽  
Dry Weight ◽  
Stomatal Resistance ◽  
Carbon Dioxide Exchange ◽  
Shoot Dry Weight ◽  
Pisum Sativum L

Compensation between carbon dioxide exchange rate per unit photosynthetic area (CER) and total photosynthetic area (TPA) of a plant was examined in field-grown pea (Pisum sativum L.). Eight near-isogenic lines of cv. Alaska, representing all possible phenotypes of the genes af (leaflets transformed to tendrils), st (reduced stipule area) and tl (tendrils transformed to leaflets), were examined. The CER was measured on the leaflets (AfAf), tendrils (afafTlTl) or minute leaflets (afaftltl). The TPA was significantly reduced by the st gene in AfAf types (normal leaflets) with an apparently associated increase in CER. The st gene also significantly reduced the TPA in afaf types but there was no associated increase in CER. Tendrils had a lower CER than normal leaflets and comprised 22% of the TPA of the semi-leafless (afafStStTlTl) type. Crosses were made between a semi-leafless pea and four normal-leafed types previously selected for high or low CER. The CER means (normal leaflets) of the F1 progeny showed variability which was related to parental values. This was also true for the CER means (tendrils) of the populations of semi-leafless F2 segregants showing that genetic variability for CER can exist in tendrils. In the F2, tendril CER was correlated negatively to stomatal resistance and positively to chlorophyll content and final shoot dry weight (biomass). Genetic improvement in CER may be important when a plant ideotype requires substantial reduction in TPA.Key words: Photosynthesis, pea, chlorophyll content, stomatal resistance, Pisum sativum

Assessing the effect of light intensity and light wavelength spectra on the photoreduction of formic acid using a graphene oxide material

2020 ◽  
Vol 18 (8) ◽  
Author(s):  
Luis A. Ramos-Huerta ◽  
Lotte Laureys ◽  
Alexis G. Llanos ◽  
Patricio J. Valadés ◽  
Richard S. Ruiz ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Graphene Oxide ◽  
Light Intensity ◽  
Formic Acid ◽  
Reaction Rates ◽  
Operating Conditions ◽  
Initial Reaction ◽  
Oxide Material ◽  
Methanol Production ◽  
Effect Of Light

AbstractPhotocatalysis has been a topic of interest in recent years for both, oxidation and reduction reactions, and although there is a broad variety of research regarding photocatalytic materials and the reaction itself, studies on reactor design and related phenomena, radiation transfer and its direct impact on reaction extent specifically, are usually neglected. From this end, the present work focuses on the elucidation of the effect of light intensity and wavelength spectra in the visible light region during the photoreduction reaction of formic acid using graphene oxide as a promising catalyst. By using formic acid, one of the main intermediaries in the photoreduction of carbon dioxide, the possibility of methanol production is evaluated without the thermodynamic constraints presented by carbon dioxide. A graphene oxide material, synthetized through a modified Hummer’s method, is assessed for the reduction of formic acid evaluating four different light sources (red, green, blue and white). An analysis of energy balances in the reaction set-up allows the determination of both the energy absorbed by the GO photocatalyst and isoactinity conditions at studied radiative operating conditions. At an isoactinity environment, the adsorption rate of formic acid and production rate of methanol are then evaluated, relating them to the absorbed energy achieved at the wavelength spectra and light intensities evaluated; IR spectroscopy is utilized to follow formic acid concentration as well as methanol production. The largest initial reaction rate (ca. 57%) relates to the use of the red wavelength at its largest intensity. Reaction rates at larger times start to be apparent being affected by adsorption, reaction and radiation conditions. The maximum conversion, 14%, is attained by using the white wavelength spectra at its lowest intensity. Thus, higher intensities will not necessarily yield higher conversions, nor the highest reaction rates. This, in turn, poses the necessity of quick, reliable assessments for whichever catalyst used in this type of reactions that leads to the correct election of operating conditions that maximize the product yield. Independent evaluation for every wavelength within the visible spectra and assessing carbon dioxide photoreduction are future steps into the elucidation of solar fuel production feasibility.

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