Formation Of Photosynthetic Pigments Research Articles

CONTENT AND RATIO OF PHOTOSYNTHETIC PIGMENTS IN STIPULES OF WINTER PEA WITH USING DIFFERENT GROWING TECHNOLOGIES

The article describes the results of research on the content and ratio of photosynthetic pigments in the stipules of winter peas using different cultivation technologies. The objects of the study were winter pea plants (Pisum sativum L.) of variety NS Moroz, plant growth regulator (PGR) Endofit L1 RK, bacterial preparation Bioinoculant BTU-r, microfertilizers «LF-Bobovi» and Biobor 140. The purpose of our research was to study the formation of photosynthetic pigments of winter pea plants under the action of growth regulator Endophyte L1 RK, bacterial preparation Bioinoculant BTU-r, their complex applying and foliar treatment systems with microfertilizers «LF- Bobovi» and Biobor 140. Analysis of chlorophyll and carotenoid content in alcohol extract (96.0%) was performed using a spectrophotometer Ulab − 102UV (China) at different values of wavelength: λ = 441; λ = 649; λ = 665. The volume of the working solution was 25 ml. Calculations of these indexes were performed according to the formulas of H. K. Lichtenthaler. During the study period, the influence of plant growth regulator, bacterial preparation, and foliar fertilization on the content of chlorophyll a and b, their sum, and concentration of carotenoids in the stipules of winter pea plants were evaluated. The research results indicate the dependence of these indicators on the use of the growth regulator and the bacterial drug, as well as on foliar fertilization. It was found that the implementation of foliar treatment in the phase of 3-5 stipules and complex use (in phases 3-5 of stipules and buttons) phase with tank mixtures of micro fertilizers «LF- Bobovi» (1.5 l / ha and 2.5 l / ha) and Biobor 140 (1.0 l / ha) led to an increase of the content of chlorophyll a and b, their total amount and carotenoid content. The highest content of chlorophylls a and b, their sum, and carotenoids in the stipules of winter pea plants were in the variant with the combined use of pre-sowing seed treatment with growth regulator Endophyte L1 RK (0.01 l / t), bacterial preparation Bioinoculant BTU-r (2 l / t) and at foliar treatment with microfertilizers «LF- Bobovi» (1.5 l / ha and 2.5 l / ha) and Biobor 140 (1.0 l / ha).The search for ways and opportunities to increase the grain yield of winter pea varieties Moroz due to the introduction of new technological methods of its cultivation remains relevant. A possible solution to the problem of improving the productivity of winter peas is the use of different mechanisms of action of plant growth regulators, inoculation with symbiotic microorganisms, and foliar feeding with tank mixtures of chelated microfertilizers.

Impacts of zebra chip disease and irrigation on leaf physiological traits in potato

Zebra chip disease (ZC) is caused by the fastidious, phloem-limited, bacterial pathogen ‘Candidatus Liberibacter solanacearum (Lso), which is transmitted from plant to plant by the potato psyllid (Bactericera cockerelli (Sulc)). Understanding how ZC impacts potato (Solanum tuberosum L.) physiology, could help growers in making more informed crop management decisions. Measurements of instantaneous leaf physiological responses, such as photosynthetic CO2 uptake and transpiration on the leaf surface, can be used not only for fast screening of affected plants in the field but also for optimizing irrigation management. Over the 2019 and 2020 field seasons, we characterized time-course photosynthetic physiological responses of potato plants infested by potato psyllids (B. cockerelli (Sulc)) carrying the Lso haplotypes A+B. Potato plants were subjected to different variable-rate irrigation (VRI) treatments (100%, 80%, and 60% of field capacity of the soil) through a center-pivot sprinkler system to examine the impact of the disease on key physiological parameters of photosynthesis and transpiration. Leaf and air temperatures, and hyperspectral profiles of the canopy were also measured and compared. The measurements were made during midday weekly from 25 to 50 days after plant infestation (DAI) with bacteriliferous psyllids. The results showed that many of the measured variables, including stomatal conductance, photosynthesis rate, transpiration rate, quantum yields, and normalized difference in vegetation index started to decrease beginning approximately 28–35 DAI, gradually worsening until 50 DAI, in both 2019 and 2020, as the infection proceeded. The decreases in stomatal conductance in infected plants led to decreases in photosynthesis and transpiration. In turn, reduced transpiration resulted in increased leaf temperature due to decrease in evaporative cooling on the leaf surface. Higher leaf temperatures under hot and dry conditions with high light intensity during the daytime would further reduce photosynthetic light harvesting, which is supported by our data, indicating the damage to the photosynthetic pigment formation and machinery. These findings support the previous report that increased leaf temperature in infected plants may have been derived from the closure of stomata in hypersensitive reactions to infection. These stomatal responses were detected within 28 DAI, a week earlier than the differences in hyperspectral profiles observed 35 DAI, and could be implemented in early disease detection strategiesusing measurements of leaf temperature.

Impact of metal-oxide nanoparticles on growth, physiology and yield of tomato (Solanum lycopersicum L.) modulated by Azotobacter salinestris strain ASM.

The current study for the first time demonstrates the interference of a free-living, N2-fixing, and nanoparticle (NP) tolerant Azotobacter salinestris strain ASM recovered from metal-polluted soil with tomato plant-metal oxide NPs (ZnO, CuO, Al2O3, and TiO2) interactions in a sandy clay loam soil system with bulk materials as control. Tomato plants were grown till full maturity in soils amended with 20-2000mgkg-1 of each metal-oxide NP with and without seed biopriming and root-inoculation of A.salinestris. A.salinestris was found metabolically active, producing considerably high amounts of bioactive indole-3-acetic-acid, morphologically unaffected, and with low alteration of cell membrane permeability under 125-1500 μgml-1 of NPs. However, ZnO-NPs slightly alter bacterial membrane permeability. Besides, A.salinestris secreted significantly higher amounts of extracellular polymeric substance (EPS) even under NP exposure, which could entrap the NPs and form metal-EPS complex as revealed and quantified by SEM-EDX. NPs were also found adsorbed on bacterial biomass. EPS stabilized the NPs and provided negative zeta potential to NPs. Following soil application, A.salinestris improved the plant performance and augmented the yield of tomato fruits and lycopene content even in NPs stressed soils. Interestingly, A.salinestris inoculation enhanced photosynthetic pigment formation, flower attributes, plant and fruit biomass, and reduced proline level. Bacterial inoculation also reduced the NP's uptake and accumulation significantly in vegetative organs and fruits. The organ wise order of NP's internalization was roots>shoots>fruits. Conclusively, A.salinestris inoculation could be an alternative to increase the production of tomato in metal-oxide NPs contaminated soils.

Physiological disruption, structural deformation and low grain yield induced by neonicotinoid insecticides in chickpea: A long term phytotoxicity investigation

Arbitrary use of insecticides in agricultural practices cause severe environmental hazard that adversely affects the growth and productivity of edible crops. Considering theses, the aim of the present study was to evaluate the toxicological potential of two neonicotinoid insecticides, imidacloprid (IMID) and thiamethoxam (THIA) using chickpea as a test crop. Application of insecticides at three varying doses revealed a gradual decrease in biological performance of chickpea plants which however, varied noticeably among insecticides and their doses. Significant (P ≤ 0.05) decline in germination efficiency, length of plant organs under in vitro condition was observed in a dose related manner. Among insecticides, 300 μgIMIDkg−1 (3X dose) maximally and significantly (P ≤ 0.05) inhibited germination efficiency, vigor index, length, dry matter accumulation, photosynthetic pigment formation, nodule volume and mass, nutrient uptake, grain yield and protein over untreated control. In contrast, 75 μgTHIAkg−1 (3X dose) considerably declined the leghaemoglobin content, shoot phosphorus and root nitrogen. Enhanced expression of stress biomarkers including proline, malondialdehyde (MDA), and antioxidant defence enzymes was noticed in the presence of insecticides. For instance, at 3X IMID, shoot proline, MDA, ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and peroxidase (POD) were increased significantly (P ≤ 0.05) by 66%, 81%, 36% and 35%, respectively. Additionally, electrolyte leakage was maximally (77%) increased at 3X dose of IMID, whereas, H2O2 in foliage was maximally accumulated (0.0156 μ moles min−1 g−1 fw) at 3X dose of THIA which was 58% greater than untreated foliage. A clear distortion/damage in tip and surface of roots and ultrastructural deformation in xylem and phloem of plant tissues as indication of insecticidal phytotoxicity was observed under scanning electron microscope (SEM). For oxidative stress and cytotoxicity assessment, root tips were stained with a combination of acridine orange and propidium iodide, and Evan blue dyes and examined. Confocal laser scanning microscopic (CLSM) images of roots revealed a 10-fold and 13.5-fold increase in red and blue fluorescence when 3X IMID treated roots were assessed quantitatively. Conclusively, the present investigation recommends that a careful and protected approach should be adopted before the application of insecticides in agricultural ecosystems.

Content of chloroplasts in the leaves of plants spring durum wheat in depending of mineral nutrition

Shown results of the three-years study (2012-2014 gg.). For determination dynamics of formation pigments of photosynthesis in spring durum wheat plants with actions of different fertilizing options. Was established a significant impact of studied technology elements on chlorophyll content in the leaves of plants. It is established that using of foliar feeding on background of main fertilizer has a positive impact on productivity and quality of the studied varieties. Was find out the role of plant nutrition system that enables to control formation of photosynthetic pigments in leaves of spring durum wheat plants. Was established, that optimization of fertilizing mode provides a complete disclosure of resource potential of plants thereby increasing yield.

Abscisic Acid-Induced Starch Accumulation in Bioenergy Crop Duckweed Spirodela polyrrhiza

Spirodela polyrrhiza, a fast-growing duckweed with high starch and low lignin content, shows promise as a feedstock for bioenergy. Abscisic acid (ABA) is a biological hormone that controls plant growth and stress response. The effects of different ABA concentrations (0, 1.0 × 10−5, 1.0 × 10−4, 1.0 × 10−3, 1.0 × 10−2, and 1.0 × 10−1 mg/L) on duckweed biomass growth, carbon dioxide fixation, formation of photosynthetic pigments (Chlorophyll a (Chla), Chlorophyll b (Chlb), and carotenoids), the activities of soluble starch synthase (SSS) and starch branching enzyme (SBE), and the starch content of biomass were investigated in this study. ABA at concentrations lower than 1.0 × 10−3 mg/L promoted carbon dioxide fixation, whereas it inhibited carbon dioxide fixation at concentrations over 1.0 × 10−3 mg/L. ABA enhanced SSS and SBE activities at concentrations lower than 1.0 × 10−2 mg/L. ABA treatment increased the content of Chla, Chlb, and carotenoids and resulted in the enhancement of starch content. Chla content gradually increased with the increasing concentration of ABA (1.0 × 10−5 to 1.0 × 10−2 mg/L). After culturing for 10 days, starch content in 1.0 × 10−2 mg/L ABA medium reached 35.3% of dry weight (DW), which was the highest level in this study. This suggests that there is a great potential to develop a technology to increase starch accumulation in duckweed which can be used as an alternative to corn, sugarcane, or other food crops as a starch source.

Peculiarities of the effect of octyl- and nonylphenols on the growth and development of microalgae

The influence of hormonelike xenobiotics (HLXs), i.e., octyland nonylphenols, on microalgae has been investigated. Studies have shown that the effect of HLXs on the life and activity of the hydrobionts under consideration depends on their chemical structure, concentration, and algae taxonomic group. Nonylphenols (NPs) have shown greater toxicity than that of octylphenols (OPs) for all algae studied: the concentrations of NPs (EC50) that induce 50% inhibition of the growth of microalgae are 1.5–3.3 times lower than EC50 for OP (depending on the culture). It has been established that blue-green algae are more sensitive to alkylphenols, while green algae are less sensitive to them. The 20–30% stimulation of the growth of cyanobacteria of genus Microcystis was revealed in the presence of low NP and OP concentrations. Under stress conditions induced by alkylphenols, changes in the formation of photosynthetic pigments are observed and the stimulation of the synthesis of algotoxins and odorants (geosmin and 2-methylisoborneol) is possible.

Light–dark duration alternation effects on Rhodobacter sphaeroides growth, membrane properties and bio-hydrogen production in batch culture

The effects of light–dark duration alternation on bacterial growth and hydrogen (H2) production performance of Rhodobacter sphaeroides MDC 6522 from Armenian mineral springs were firstly investigated in batch culture. Five types of light–dark duration were applied: 1st culture was illuminated continuously (control); 2nd and 3rd cultures were illuminated after inoculation during 24–48 h, then dark conditions were applied; 4th and 5th cultures were illuminated after 24–48 h dark period. R. sphaeroides did not grow well in the dark conditions, but growth and H2 production were restored upon illumination. When culture was illuminated after 24 h dark period, H2 yield was maintained at a constant high level during 96–144 h, and duration of photo-fermentation was delayed up to 144 h, compared to the control. When culture was illuminated till H2 production started (48 h), and then dark conditions were applied, H2 production ability of R. sphaeroides persisted during the growth up to 120 h, whereas in the control cells H2 production was not observed. Moreover, the results indicated that light–dark alternation affected the formation of photosynthetic pigments and membrane H+ conductance. This study is of significant for understanding of bacterial metabolism regulation mechanisms and for application of purple bacteria in H2 production biotechnology.

Динаміка формування піґментних речовин у листках рослин пшениці твердої ярої за дії різних варіантів ценотичної напруги між рослинами в посівах

Представлені результати трирічних досліджень(2008–2010 рр.) щодо визначення динаміки форму-вання піґментів фотосинтезу в рослинах пшеницітвердої ярої сорту Харківська 41 за дії різних ва-ріантів способу сівби та норм висіву насіння.Встановлено значний вплив досліджуваних елементівтехнології на вміст хлорофілів і каротиноїдів улистках рослин. Більших змін вміст пігментів фо-тосинтезу зазнавав за дії фактора норми висіву.Загальною закономірністю було зменшення вмістухлорофілів і каротиноїдів у листках рослин за умо-ви зменшення норми висіву та оптимізації розпо-ділу рослин за площею живлення. Виявлено, щопроведення сівби смуговим способом дає змогупроводити її в більш широкому діапазоні норм ви-сіву без істотного зменшення вмісту піґментівфотосинтезу в листовій масі рослин. У ході дослі-джень визначено пряму кореляційну залежністьміж вмістом піґментів і зерновою продуктивніс-тю колоса головного пагона рослин.
 The results of the three-year study (2008–2010) to determine the dynamics of the formation of photosynthetic pigments in plants of durum spring wheat varieties Kharkiv 41, depending on the different ways of planting and seeding rate are given in the article. A significant effect of the studied elements of the technology on the content of chlorophyll and carotenoids in the leaves of plants was found. The content of photosynthetic pigments was changed to a large extent at the impact factor of the seeding rate. The general regularity was to reduce the content of chlorophyll and carotenoids in the leaves of plants at effective seeding rate and optimization of the distribution of plants over the area of ​​nutrition. The studies identified a direct correlation between the content of pigments and grain productivity of the ear of the main shoot of the plant.

Cultivation of Aquincola tertiaricarbonis L108 on the fuel oxygenate intermediate tert-butyl alcohol induces aerobic anoxygenic photosynthesis at extremely low feeding rates

Aerobic anoxygenic photosynthesis (AAP) is found in an increasing number of proteobacterial strains thriving in ecosystems ranging from extremely oligotrophic to eutrophic. Here, we have investigated whether the fuel oxygenate-degrading betaproteobacterium Aquincola tertiaricarbonis L108 can use AAP to compensate kinetic limitations at low heterotrophic substrate fluxes. In a fermenter experiment with complete biomass retention and also during chemostat cultivation, strain L108 was challenged with extremely low substrate feeding rates of tert-butyl alcohol (TBA), an intermediate of methyl tert-butyl ether (MTBE). Interestingly, formation of photosynthetic pigments, identified as bacteriochlorophyll a and spirilloxanthin, was only induced in growing cells at TBA feeding rates less than or equal to maintenance requirements observed under energy excess conditions. Growth continued at rates between 0.001 and 0.002 h(-1) even when the TBA feed was decreased to values close to 30 % of this maintenance rate. Partial sequencing of genomic DNA of strain L108 revealed a bacteriochlorophyll synthesis gene cluster (bchFNBHL) and photosynthesis regulator genes (ppsR and ppaA) typically found in AAP and other photosynthetic proteobacteria. The usage of light as auxiliary energy source enabling evolution of efficient degradation pathways for kinetically limited heterotrophic substrates and for lowering the threshold substrate concentration Smin at which growth becomes zero is discussed.

Spectral conversion of light for enhanced microalgae growth rates and photosynthetic pigment production

The effect of light conditions on the growth of green algae Chlorella vulgaris and cyanobacteria Gloeothece membranacea was investigated by filtering different wavelengths of visible light and comparing against a model daylight source as a control. Luminescent acrylic sheets containing violet, green, orange or red dyes illuminated by a solar simulator produced the desired wavelengths of light for this study. From the experimental results the highest specific growth rate for C. vulgaris was achieved using the orange range whereas violet light promoted the growth of G. membranacea. Red light exhibited the least efficiency in conversion of light energy into biomass in both strains of microalgae. Photosynthetic pigment formation was examined and maximum chlorophyll-a production in C. vulgaris was obtained by red light illumination. Green light yielded the best chlorophyll-a production in G. membranacea. The proposed illumination strategy offers improved microalgae growth without resorting to artificial light sources, reducing energy use and costs of cultivation.

Formation of photosynthetic pigments and quinones and development of photosynthetic activity in barley etioplasts during greening in intermittent and continuous white light

The appearance and development of photosynthetic activity, and the accumulation of chlorophylls, carotenoids and quinones, was investigated in etiolated barley shoots (Hordeum vulgare L. cv. Villa) during greening in flash light, periodic light‐dark cycles, and continuous white light. Greening and the development of photosynthetic activity was delayed in flash and periodic light compared to continuous white light. Photosystem II activity occurred after 6 light‐dark cycles and increased continuously during greening. After 3 h greening in continuous white light, photosystem II activity appeared with a very high rate and decreased to that of a green leaf after 50 h greening. Parallel to the development of photosynthetic activity, light stimulated the biosynthesis of prenyllipids. Moreover, chlorophylls and those carotenoids and quinones that are contained in etioplasts in relatively small amounts, were particularly enhanced in their biosynthesis. Chlorophyll a was synthesized without a lag phase during greening in flash light, whereas a 2 h lag phase occurred in continuous white light. In all three modes of illumination the formation of chlorophyll a exceeded that of chlorophyll b. After 4 flashes and 2 light‐dark cycles, chlorophyll b could be detected with a very high initial a/b ratio. Higher chlorophyll a/b ratios were reached after 200 flashes (a/b=10.9) and 50 light‐dark cycles (a/b=6.6) than after 50 h continuous white light (a/b=3.3). The formation of carotenes, lutein, violaxanthin and neoxanthin was also enhanced by light. This was also confirmed for plast‐ouinone‐9. ş‐tocopherol,α‐tocoquinone and phylloquinone. A comparison of the carotenoid and quinone composition of the differentiating thylakoid membrane before and after onset of photosynthesis, reveals that the photosynthetic membrane is already equipped with photosynthetic pigments and quinones before the appearance of photosystem II activity. It is concluded that during development of the photo‐synthetic apparatus the thylakoid membrane with its structural and functional constituents is formed first. In a second and slower process the water splitting enzyme system and enzymes of the Calvin cycle are activated.

Orientation of oxygen in oxyhaemoproteins and its implications for haem catabolism

Haem is degraded to bile pigments in the catabolism of haemoproteins in mammals and in the formation of photosynthetic pigments in algae. The first stage of this reaction involves oxygen attack at one of the four methene-bridge carbon atoms, which is ultimately eliminated as CO(ref. 1). The four bridges are not sterically equivalent (Fig. 1) and the bilirubin in mammalian bile and algal bile pigments consists almost exclusively of the alpha-isomers. Little is known about the structures of the ring-cleaving enzymes responsible, although microsomal haem oxygenase, which catalyses the breakdown of haem to biliverdin in mammals, has very similar spectroscopic properties to myoglobin. The degradation process has been simulated in vitro by a 'coupled oxidation' method in which the proportions of the four possible isomeric products depend on the nature of the globin moiety to which the haem is bound. We report here the use of an interactive computer display system to explore the relative accessibilities of the four methene bridges to a haem-bound oxygen molecule in myoglobin and in the alpha and beta chains of haemoglobin. Our calculated interaction energies agree well with the proportions of the four isomers that are observed experimentally.

Inhibition by adenine compounds of the induced formation of photosynthetic pigments in <italic>Rhodopseudomonas spheroides</italic> cells under dark-semiaerobic conditions

Inhibition by adenine compounds of the induced formation of photosynthetic pigments in <italic>Rhodopseudomonas spheroides</italic> cells under dark-semiaerobic conditions

PHOSPHOLIPID SYNTHESIS BY RHODOPSEUDOMONAS SPHEROIDES IN RELATION TO THE FORMATION OF PHOTOSYNTHETIC PIGMENTS.

The concentration of phospholipids in pigmented Rhodopseudomonas spheroides was higher than that in organisms lacking the photosynthetic pigments; the amounts of lipid phosphorus/mg. protein were, respectively, 157 and 90 mμmoles. Phosphatidylethanolamine comprised about 40% of the phospholipids, the remainder consisting of phosphatidic acid, phosphatidylglycerol and phosphatidylcholine. The phospholipids were confined to the membrane fraction of the organisms. As organisms adapted from the non-pigmented to the pigmented state the amount of lipid phosphorus/mg. protein increased. Experiments with radioactive phosphate showed phosphatidyl glycerol to incorporate label more rapidly than the other phospholipids. It is suggested that the formation of the photosynthetic pigments may be accompanied by modifications to the membrane structure so that it can accommodate more phospholipids.