scholarly journals Contents of photosynthetic pigments and ratios of chlorophyll a/b and chlorophylls to carotenoids (a+b)/(x+c) in C4 plants as compared to C3 plants

2021 ◽  
Author(s):  
H.K. LICHTENTHALER ◽  
F. BABANI
2019 ◽  
Vol 52 (1) ◽  
pp. 74-78
Author(s):  
S. Buhăianu ◽  
Doina Carmen Jităreanu

Abstract Chlorophylls from plants are photosynthetic pigments. Their quantity offers valuable informations about photosynthetic activity, growing and developing of plants. Photosynthetic pigments decrease quantitatively during senescence process or in stress conditions. The present study has been realized in laboratory conditions with material harvested from spontaneous flora. The purpose of this research was the investigation of variations of chlorophyll content from samples of biological material collected from Nepeta pannonica L. and Abies alba Mill. plants, from Câmpulung Moldovenesc and Cacica areas, Suceava county, Romania. The targeted phenophases were growth and flowering. There were realized acetonic extracts from samples for spectrophotometric determinations. Obtained data were processed to estabilish chlorophyll a and b content. There were observed that at Abies alba species, from both locations, the chlorophyll a content grew during flowering phenophase, while the chlorophyll b content had little variations. At Nepeta pannonica species, the chlorophyll a and b content decreased visibly during the flowering, due to stress. Leaves of plants from this species presented a intense green color in the growing phenophase, while during flowering phenophase they had a purple or yellow coloration. Obtained results revealed a different dynamics of chlorophyll content at studied species.


2021 ◽  
Vol 4 (11(75)) ◽  
pp. 11-16
Author(s):  
А. Kurylenko ◽  
O. Kurylenko ◽  
О. Kuchmenko ◽  
V. Havii

Purpose. The aim of the study is to investigate the effect of pre-sowing treatment of winter rye seeds of Synthetic 38 and Zabava with compositions of metabolically active substances on the content of photosynthetic pigments in plant leaves at different phases of ontogenesis. Materials and methods. The research materials were winter rye varieties Synthetic 38 and Zabava, and combinations of metabolically active substances: vitamin E (10-8M), paraoxybenzoic acid (0,001%), methionine (0,001%), ubiquinone-10 (10-8M) and MgSO4 (0,001%). The research scheme provided 4 options: 1) control (untreated seeds); 2) seeds, treated with a composition of substances: vitamin E + paraoxybenzoic acid + methionine + MgSO4; 3) seeds treated with a composition of substances: vitamin E + paraoxybenzoic acid + methionine; 4) seeds, processing by composition of substances: vitamin E + ubiquinone-10. Studies were conducted in the following phases of rye development: tillering, tubing, earing, flowering. The content of pigments - chlorophyll a, b and the total content of chlorophyll in the leaves of rye plants was determined by spectrophotometric method. Results and conclusions. It was demonstrated for the first time that the use of compositions of metabolically active compounds for pre-sowing treatment of winter rye varieties Synthetic 38 and Zabava leads to an increase of main chlorophyll, chlorophyll a and b in plant leaves in the dynamics from tillering to flowering. The composition consisting of vitamin E, para-oxybenzoic acid, methionine and MgSO4 showed the greatest efficiency. The effectiveness of this composition may be due to the complex action of all metabolically active compounds that are part of it. The obtained results may indicate a potentially more efficient absorption and conversion of energy by plants and the positive effect of these compositions on the photosynthesis of winter rye plants. Substances that have shown their effectiveness can be used as components of stimulants.


Author(s):  
Mary Jane Perry

Phytoplankton plays a critical role in determining light fields of the world’s oceans, primarily through absorption of light by photosynthetic pigments (see Chapters 1 to 5). Consequently there has been considerable interest from optical researchers in determining phytoplankton absorption. Conversely, from the biological point of view, this absorption assumes paramount importance because it is the sole source of energy for photosynthesis and thus should be central to direct estimates of primary production. There are two logical parts in determining this effect of phytoplankton and in estimating primary production. One is the estimation of abundance, and the other is estimation of specific effect or specific production rate. The earliest estimates of phytoplankton abundance were based on cell counts. From the time of Francis A. Richards’ Ph.D. dissertation, however, measurement of chlorophyll a concentration per unit of water volume, because of its relative ease, has assumed a central role in abundance estimation. Physiological studies and technological advances in optical instrumentation over the last decade lead me to question whether the continued use of chlorophyll a concentration to estimate phytoplankton abundance was wise either from the viewpoint of narrowing confidence intervals on estimates of absorption and production or from the viewpoint of mechanistic understanding of the processes involved. The measurement of chlorophyll a has become such a routine tool of biological oceanography, however, that the reasons for my heresy require elaboration. Some of the reasons are not too subtle. Chlorophyll a exists with other photosynthetic pigments in organized arrays associated with photosynthetic membranes. The function of these arrays is to harvest photons and transfer their energy to the specialized reaction center complexes that mediate photochemistry (see Chapter 9). The size of the arrays or packages and the ratio of chlorophyll a molecules to other light-harvesting pigments within the packages vary with phytoplankton cell size, total irradiance and its spectral distribution, as well as with other environmental parameters. It is well known that dark-adapted (= light-limited) cells increase their complements of photopigments. This plasticity in pigment packaging is evidenced in the variability of chlorophyll a-specific absorption coefficients. Simple optical models based only on chlorophyll a concentrations cannot be accurate or precise unless the effects of pigment packaging are considered.


1979 ◽  
Vol 34 (7-8) ◽  
pp. 582-587
Author(s):  
Framçoise Techy ◽  
Monique Dinant ◽  
Jacques Aghion

Abstract The spectroscopic (visible) properties of pigment-bearing lipid and protein particles extract­ ed from milk show that: 1) chlorophylls a and b bound to separate particles can form aggregates provided their relative concentration is high enough. Neither pheophytin a nor β-carotene, in the same conditions, form observable aggregates. 2) Chlorophylls a and b can co-aggregate when they are bound to the same particles. Pheophytin a as well as β-carotene seem to prevent the aggregation of chlorophyll a. β-carotene has no effect on the aggregation of chlorophyll b.


2016 ◽  
Vol 67 (12) ◽  
pp. 1991 ◽  
Author(s):  
Miguel C. Leal ◽  
Igor C. S. Cruz ◽  
Carlos R. Mendes ◽  
Ricardo Calado ◽  
Ruy K. P. Kikuchi ◽  
...  

Intertidal environments are boundaries between marine and terrestrial ecosystems that are subject to rapid fluctuations across tidal cycles. This study investigates, for the first time, the photobiology of symbiotic zoanthids inhabiting different tidal environments: subtidal, intertidal pools and intertidal areas exposed to air during low tide. More specifically, we assessed the photochemical efficiency, Symbiodinium density and photosynthetic pigments profile of Zoanthus sociatus during low tide. Photochemical efficiency was lower and cell density higher in air exposed zoanthids. The profile of photosynthetic pigments also varied significantly among tidal habitats, particularly photoprotective pigments such as dinoxanthin and diadinoxanthin. Differences were also observed for the pigment content per cell, but the proportion of particular pigments (peridinin/chlorophyll-a and diatoxanthin+diadinoxanthin/chlorophyll-a) remained stable. Results suggest that aerial exposure conditions induce reversible downregulation of photochemical processes but no photophysiological impairment or bleaching. These findings provide a baseline for future studies addressing the prevalence of these overlooked cnidarians in environmentally dynamic reef flats.


2017 ◽  
Vol 16 (2) ◽  
pp. 76-85 ◽  
Author(s):  
Agáta Fargašová

Abstract In this study, the phytotoxicity of disinfectants prepared on the base of sodium hypochlorite was determined. For our tests two commercial products, Savo and Dom Amor, as well as 10% NaClO solution were used. While Savo contained only NaClO, Dom Amor contained NaClO and earthworm enzymes. Products on the base of NaClO are used in households for cleaning and disinfection of floors, furniture, sanitary and kitchen equipment. Savo may be used for the disinfection of drinking waters as well. Products with NaClO are also used for bacteria, algae and pathogens reduction in irrigation waters. As a subject, young seedlings of mustard Sinapis alba L. were used for the study of chronic toxicity. The observed parameters of the inhibition of roots and shoots growth, dry (DM) and fresh (FM) mass as well as photosynthetic pigments production (chlorophyll a, b, carotenoids) and water content in the plants were determined. The results point out that Dom Amor was the most toxic for S. alba seedlings growth and the rank order of the FAC contents for both plant parts was arranged as: Dom Amor > Savo > NaClO. All disinfectants reduced the DM and FM of roots; however, they stimulated biomass production in the shoots. On the basis of the obtained results it could be concluded, that disinfectants stimulated photosynthetic pigments production and reduced water content mainly in the roots. Dom Amor did not significantly reduced the water content in the shoots and for this parameter the following rank orders of inhibition for roots and shoots could be arranged as NaClO > Dom Amor > Savo and NaClO > Savo > Dom Amor, respectively. All commercial products increased chlorophyll a (Chla) and the carotenoids (Car) content in the shoots. As significant increase was confirmed first for Chla whose content in the presence of NaClO at concentration 24 mL/L overextended that in the control by 3.5 times. The rank orders of stimulation for Chla and Car were NaClO > Savo > Dom Amor and Dom Amor > NaClO > Savo, respectively.


Forests ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1686
Author(s):  
Haoyun Wang ◽  
Feng Wu ◽  
Min Li ◽  
Daqu Liang ◽  
Guijie Ding

Pines have heteroblastic foliage (primary and secondary needles) during seedling stage, but how heteroblastic foliage affects carbon storage and biomass accumulation, contributing to seedling quality, is unclear. We investigated the influences of heteroblastic foliage on photosynthetic physiological characteristics, non-structural carbohydrate (NSC) and biomass accumulation in current-year seedlings; the key factors determining biomass accumulation were mainly determined by principal component screening, Spearman correlation, and path analysis. The results indicated that (1) primary needles have high photosynthetic pigments (chlorophyll a and total chlorophyll), net photosynthetic rates (Pn), the potential maximum photochemical efficiency (Fv/Fm), and leaf instantaneous water use efficiency (WUEi), whereas higher non-photochemical quenching (NPQ) suggested that sudden light increases induce the initiation of quenching mechanism in primary needles; additionally, secondary needles had a lower transpiration rate (Tr), limiting stomata (Ls), and light saturation point. (2) Secondary needles promoted soluble sugar (fructose and glucose) increases in leaves compared to that of primary needles and increased the leaf biomass accumulation (from 47.06% to 54.30%), enhancing the overall ability of photosynthetic organs; additionally, secondary needles can enhance the proportion of starch storage in the roots, and NSC accumulation was significantly increasing in the seedling leaves and roots. (3) Photosynthetic pigments (carotenoids, chlorophyll a, and total chlorophyll) had direct positive effects on primary needle seedling (PNS) biomass and promoted biomass by indirectly increasing soluble sugar synthesis in the stems. The Pn was the main physiological factor determining PNS biomass accumulation. In addition, the WUEi, Ls, and NPQ had direct negative effects on PNS biomass accumulation, inhibiting photosynthesis to limit seedling growth. Considering the functional traits in heteroblastic foliage is necessary when assessing different leaf types of Pinus massoniana (Lamb.) seedlings, in particular those threats implicated in light, water, and temperature relations. Our results can be beneficial to guide the establishment of seedling management and afforestation measures.


2020 ◽  
Vol 5 (2) ◽  
pp. 8-13
Author(s):  
Aleksei Bakunov ◽  
Aleksei Milekhin ◽  
Sergei Rubtsov ◽  
Sergei Shevchenko

The aim of the research is increasing potato yield in dry conditions of the Middle Volga region. The research was carried out on the experimental field of the Samara Scientific Research Institute of Agriculture – branch of the Sa-mara Research Center of the Russian Academy of Sciences. The variety testing plant nursery included 28 varieties of potatoes of domestic selection. Udacha, Zhigulevsky, Arosa and Gala breeds were the standard varieties. The plant material was planted out in two replications with 25 plants in each. To determine the content of photosynthetic pigments, extracts were prepared from ten potato leaves of each breed in 100% acetone. Measurements were per-formed by spectrophotometry. To measure the amount of chlorophyll a, the wavelength of 665 nm, chlorophyll b – 649 nm, and carotenoids – 440 nm were used. The concentration of pigments was determined by using Wettstein formulas. When harvesting, the potato yield was taken into account. The average concentration of chlorophyll a in the studied breeds was 0.92 mg/g, the average concentration of chlorophyll b was 0.62 mg/g, and one of carote-noids was 0.27 mg/g. Potato breeds with high concentration of photosynthetic pigments were identified. A reliable average dependence of the yield of potato breeds on the concentration of chlorophyll b in plants was revealed. The correlation coefficient was 0.42. There is no reliable dependence tested of yield on the concentration of chlorophyll a and carotenoids. Potato productivity is associated with a significant negative relationship with the ratio of both a and b chlorophyll concentrations. The most highly productive varieties were characterized by a high content of two varieties of chlorophyll. A high concentration of chlorophyll b or a minimum ratio of chlorophyll a and b concentra-tions can be tentatively recommended as a consequential sign for identifying potato breeds that are highly adapted to high air temperature and insufficient moisture.


2021 ◽  
Vol 25 (9) ◽  
pp. 1575-1580
Author(s):  
S. Abdulsalam ◽  
M.K. Yahaya ◽  
L.O. Habib ◽  
N.O. Ugbenyo

The effects of Na2EDTA and HNO3 on Ni2+ uptake by Spinacia oleracea seedlings replanted inhydroponic culture in a greenhouse was investigated. Eight week old seedlings, were exposed to various doses of Ni2+ (0, 1000, 2000, and 4000 mg/L) as NiSO4, at (0, 500 and 3000 mg/L) Na2EDTA and ( 0, 500 and 3000 mg /L) HNO3 in different combinations. There was a substantial increase in nickel uptake in chelated treatments (p < 0.05) compared to unchelated treatments of same concentrations of Ni2+. So, chelation enhanced Ni2+ uptake in S. oleracea. During the exposure, antioxidant defense system helped the plant to protect itself from the damage. Due to increasing nickel  uptake by the plant, the photosynthetic pigments (i.e chlorophyll a, chlorophyll b and Caretenoids) gradually declined. In this study, Spinacia oleracea Seedlings and contents of the photosynthetic pigments (chlorophyll a, chlorophyll b and Caretenoids) of both chelated and unchelated hydroponic treatments were investigated. Changes in photosynthetic pigments was significant (p < 0.05) with respect to addition of EDTA and HNO3 at different concentration to different concentrations of Ni2+ compared to unchelated treatments of same concentrations of Ni2+. The Ni2+ induced translocation factor was also determined which increased significantly (P < 0.05) with increasing Ni2+ concentrations.


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