Physiological characteristics, dry matter, and active component accumulation patterns of Changium smyrnioides in response to a light intensity gradient

The effect of seven factors, namely genotype, plant maturity, nitrogen fertilizer, phosphorus fertilizer, water stress, light intensity and temperature, on the hydrogen cyanide potential (HCNp) of forage sorghum was studied in three pot experiments. Fivefold differences occurred between genotypes in HCNp, with a breeder's line, X45106, selected for low HCNp having a maximum of 520 mg HCN kg-1 DM (dry matter) compared with 2300 and 2450 mg kg-1 DM for cvs Zulu and Silk respectively. In X45 106, HCNp (mg HCN kg-1 DM) declined curvilinearly with age d (days from sowing) (HCNp=8460- 320d+ 3.1d2) and linearly in Silk (HCNp = 9020 - 110d), but the decline in Zulu was not statistically significant. Nitrogen (equivalent to 200 kg ha-1 of N) increased HCN, (P< 0.001), but more so in full light (100 mg kg-1 compared with 1430 mg kg-1) than in 50% shade (190 mg kg-1 compared with 690 mg kg-1). In one experiment, acute water stress appeared to reduce HCNp, but this was confounded with the strong decline due to aging. In another study, acute water stress had no effect on HCNp. Neither the application of superphosphate nor change in light intensity, nor change in temperature had a direct significant effect on HCNp in these studies. Breeding and selection for low HCNp appears a promising approach to ensuring that sorghum plants will provide non-toxic forage from an early stage of growth.

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Growth of Amaranthus Hybridus (African Spinach) under diffferent Daylight Intensities in the Dry Season in Southern Nigeria

Experimental Agriculture ◽

10.1017/s0014479700016987 ◽

1987 ◽

Vol 23 (2) ◽

pp. 193-200 ◽

Cited By ~ 2

Author(s):

J. M. O. Eze

Keyword(s):

Light Intensity ◽

Biochemical Parameters ◽

Dry Matter ◽

Maximum Growth ◽

Area Ratio ◽

Dry Matter Accumulation ◽

Amaranthus Hybridus ◽

Maximum Accumulation ◽

Southern Nigeria ◽

Reduced Light

SummaryThe growth of Amaranthus hybridus under different daylight intensities was assessed in terms of physical, morphological and biochemical parameters. Maximum growth in many respects was achieved at about 70% of full daylight. However, full daylight favoured chlorophyll stability and maximum accumulation of total dry matter, carbohydrate, chlorophyll and ascorbic acid. The leaf area ratio increased uniformly with decrease in light intensity. Ageing was accelerated by full daylight. Reduced light intensity reduced dry matter accumulation in the roots more than in the stems or leaves.

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Phaeodactylum Trıcornutum Kültürlerinde Biyomas Tahmini

Turkish Journal of Agriculture - Food Science and Technology ◽

10.24925/turjaf.v5i2.182-184.1145 ◽

2017 ◽

Vol 5 (2) ◽

pp. 182

Author(s):

Burcu Ak ◽

Gökhan Tamer Kayaalp ◽

Oya Işık ◽

Melis Çelik Güney

Keyword(s):

Light Intensity ◽

Chlorophyll A ◽

Optical Density ◽

Phaeodactylum Tricornutum ◽

Dry Matter ◽

Nitrogen Deficiency ◽

Regression Equation ◽

Control Group ◽

Analysis Method ◽

The Mathematical Model

Phaeodactylum tricornutum is the microalgae that is known to produce lipid. In this study, it was aimed to estimate the microalgae Phaeodactylum tricornutum dry matter cultured in the conditions of nitrogen deficiency as a stress factor, in outdoor, in photo bioreactors, by using multiple regression analysis method. In this study, diatom Phaeodactylum tricornutum (Bohlin) was cultured medium of which N was reduced by 50% and with 20% inoculation ratio. The light intensity, temperature, optical density and chlorophyll a, were measured daily. The mathematical model was formed for control group and 50 % of the N applied to the group using optical density, temperature, light intensity, chlorophyll a and without chlorophyll a. The regression equation of control group was estimated. The R2 value of control group was found 95.1% and statistically significant. Then, the regression equation was estimated for control group without chlorophyll a. The R2 value of this equation was found 94.0% and statistically significant. And then, the regression equation was estimated in 50% nitrogen. The R2 value of control group was found 92.4% and statistically significant. Finally, the regression equation was estimated in 50% nitrogen deficiency without chlorophyll a. The R2 value of this equation was found 91.7% and statistically significant.

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EFFECT OF DIFFERENT SALINITY AND LIGHT INTENSITY ON THE GROWTH OF PORPHYRIDIUM CRUENTUM

Euroasia Journal of Mathematics, Engineering, Natural and Medical Sciences ◽

10.38065/euroasiaorg.760 ◽

2021 ◽

Vol 8 (18) ◽

pp. 71-77

Author(s):

Leyla USLU

Keyword(s):

Light Intensity ◽

Chlorophyll A ◽

Optical Density ◽

Dry Matter ◽

Porphyridium Cruentum ◽

Laboratory Conditions ◽

Light Intensities ◽

Density Values

In the study, Porphyridium cruentum was cultured under laboratory conditions at 20±2°C, 16:8 (light:dark) photoperiod and continuous aeration to different salinity (20‰, 30‰, 40‰) and two different light intensities (37 µmol m-2s-1 photon and 110 µmol m-2s-1 photon) and growth was determined. Dry matter, optical density and chlorophyll a parameter were used to determine growth. The best growth was determined in culture with a salinity of 30‰ at 110 µmol m-2s-1 photon light intensity. In this group, the optical density (OD) was 1.504±0.003 and the dry matter amount was 1.327gl-1. In the case of 37µmol µmol m-2s-1 photon light intensity, the optical density values were found to be similar in groups with 30‰ and 50‰ salinity and were found to be 1.234±0.004 and 1.215±0.002, respectively. The amounts of dry matter were also similar; 1.168gl-1 and 1.159gl-1, respectively. While the lowest growth was in the culture at 37 µmol m-2s-1 photon light intensity and 20‰ salinity. The optical density obtained on the last day of this group was 1.165±0.004 and the dry matter amount was determined as 0.986gl-1. The amount of chlorophyll a was determined in the cultured groups at the best 37 µmol m-2s-1 photon light intensity.

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Physiological Characteristics of Photosynthesis in Yellow-Green, Green and Dark-Green Chinese Kale (Brassica oleracea L. var. alboglabra Musil.) under Varying Light Intensities

Plants ◽

10.3390/plants9080960 ◽

2020 ◽

Vol 9 (8) ◽

pp. 960

Author(s):

Kuan-Hung Lin ◽

Feng-Chi Shih ◽

Meng-Yuan Huang ◽

Jen-Hsien Weng

Keyword(s):

Electron Transport ◽

Energy Dissipation ◽

Light Intensity ◽

Thermal Energy ◽

Electron Transport Rate ◽

Transport Rate ◽

Physiological Characteristics ◽

Chinese Kale ◽

Thermal Energy Dissipation ◽

Dark Green

The objective of this work was to study physiological characteristics and photosynthetic apparatus in differentially pigmented leaves of three Chinese kale cultivars. Chlorophyll (Chl) fluorescence and photochemical reflectance index (PRI) measurements in green, yellow-green, and dark-green cultivars in response to varying light intensities. As light intensity increased from 200 to 2000 photosynthetic photon flux density (PPFD), fraction of light absorbed in photosystem (PS) II and PRI values in all plants were strongly lowered, but fraction of light absorbed in PSII dissipated via thermal energy dissipation and non-photochemical quenching (NPQ) values in all plants wereremarkably elevated.When plants were exposed to 200 PPFD, the values of fraction of light absorbed in PSII, utilized in photosynthetic electron transport(p), andfraction of light absorbed excitation energy in PSII dissipated via thermal energy dissipation (D), remained stable regardless of the changes in levels of Chla + b. Under 800 and 1200 PPFD, the values of p and electron transport rate (ETR) decreased, but D and NPQ increased as Chla + bcontent decreased, suggesting that decrease inChla + bcontent led to lower PSII efficiency and it became necessary to increase dissipate excess energy. On the contrary, in 2000 PPFD, leaves with lower Chla + bcontent had relatively higher p and electron transport rate (ETR) values and lower D level, as well as tended to increase more in NPQ but decrease more in PRI values. The consistent relations between PRI and NPQ suggest that NPQ is mainly consisted ofthe xanthophyll cycle-dependentenergy quenching.Yellow-green cultivar showed lower Chla + bcontent but high carotenoids/Chla + b ratio and had high light protection ability under high PPFD. The precise management of photosynthetic parameters in response to light intensity can maximize the growth and development of Chinese kale plants.

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AN ANALYSIS OF DRY MATTER PRODUCTION OF DOUGLAS-FIR SEEDLINGS IN RELATION TO TEMPERATURE AND LIGHT INTENSITY

Canadian Journal of Botany ◽

10.1139/b67-223 ◽

1967 ◽

Vol 45 (11) ◽

pp. 2063-2072 ◽

Cited By ~ 30

Author(s):

Holger Brix

Keyword(s):

Light Intensity ◽

Leaf Area ◽

Dry Matter ◽

Douglas Fir ◽

Dry Matter Production ◽

Dry Matter Distribution ◽

Pronounced Increase ◽

Light Intensities ◽

Matter Production ◽

Net Assimilation

Seedlings of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) were grown in growth chambers under all combinations of three temperatures (13, 18, and 24 °C) and three light intensities (450, 1000, and 1800 ft-c). Dry matter production of leaves, stem, and roots was determined at 65 and 100 days after germination. The leaf area produced per unit of leaf dry weight and the dry matter distribution to the plant organs was measured. Net assimilation rates between the ages of 65 and 100 days were calculated. Rates of photosynthesis per unit of leaf were determined at different light intensities and temperatures, and rates of respiration of plant top and of roots were found for different temperatures.Increasing light intensity affected dry matter production in two opposing ways: (i) it increased the rate of photosynthesis per unit leaf area, and (ii) it decreased the leaf area added per unit of dry matter produced. A pronounced increase in growth with increase in temperature from 13 to 18 °C was a result of a temperature influence on production of leaf area rather than the effect of photosynthesis per unit of leaf. Net assimilation rates decreased with increase in temperature at all light intensities.

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