Accumulation Of Photosynthetic Pigments Research Articles

Exogenous Melatonin Reinforces Photosynthesis, Antioxidant Defense and Gene Expression to Ameliorate Na2CO3 Stress in Maize.

Salt stress can seriously affect the growth and development of maize (Zea mays L.), resulting in a great yield loss. Melatonin (MT), an indole hormone, is a potential enhancer of plant tolerance against salt stress. However, the complex mechanisms of MT application in enhancing maize salt tolerance are still unclear. Herein, three-leaf seedlings of salt-susceptible P138 and its salt-resistant ethyl methane sulfonate (EMS)-104 mutant were cultured with or without 150 μM MT application under 0 and 100 mM Na2CO3 treatments for seven days, to systematically explore the response mechanisms of exogenous MT in improving the salt tolerance of maize. The results showed that salt stress triggered an escalation in reactive oxygen species production, enhanced multiple antioxidant enzymes' activities, impaired cellular membrane permeability, inhibited photosynthetic pigment accumulation, and ultimately undermined the vigor and photosynthetic prowess of the seedlings. While suitable MT application counteracted the detrimental impacts of Na2CO3 on seedlings' growth and photosynthetic capacity, the seedling length and net photosynthetic rate of P138 and EMS-104 were increased by 5.5% and 18.7%, and 12.7% and 54.5%, respectively. Quantitative real-time PCR (qRT-PCR) analysis further showed that MT application activated the expression levels of antioxidant enzyme-related genes (Zm00001d025106, Zm00001d031908, Zm00001d027511, and Zm00001d040364) and pigment biosynthesis-related genes (Zm00001d011819 and Zm00001d017766) in both maize seedlings under Na2CO3 stress; they then formed a complex interaction network of gene expression, multiple physiological metabolisms, and phenotype changes to influence the salt tolerance of maize seedlings under MT or Na2CO3 stress. To sum up, these observations underscore that 150 μM MT can alleviate salt injury of maize seedlings, which may provide new insights for further investigating MT regulation mechanisms to enhance maize seedlings' salt resistance.

Accumulation of plastid pigments in the leaves Triticum avestium L. under influence of composite recultivant Trevitan®

Aim. To investigate the efficiency of using composite recultivants TREVITAN® (RCT) according to the parameters of accumulation of the photosynthetic pigments in the leaves Triticum aestivum L. of the varieties Quintus and Licamero. Methods. The experiments were carried out on the plots of the agro-biolaboratory of Ternopil Volodymyr Hnatyuk National Pedagogical University in 4 variants (Control, TREVITAN® adjuvant, recultivants TREVITAN®, TREVITAN® adjuvant + recultivants TREVITAN®) and 3 repetitions. The content of chlorophylls a, b and carotenoids in flag leaves was defined by Welburn spectrometric method. Results. The highest content of chlorophylls was found in the leaves of both varieties of wheat in the phases of flowering and milk ripeness during autumn tillage, seeds before sowing and plants in the earing phase with recultivants TREVITAN®. Joint use of TREVITAN® adjuvant + recultivants TREVITAN® also significantly increased the content of chlorophyll in wheat leaves. Increase of carotenoids in the leaves of plants of all experimental variants on 4.2–14.6 % (variety Quintus) and on 43.2–59.5 % (variety Licamero) was defined in the phase of milk ripeness. Conclusions. The use of RCT in the technology of growing soft wheat had a significant impact on the accumulation of photosynthetic pigments in leaves during the generative phases of development.

Functional variations in efficiency of PSII during leaf ontogeny in the tropical plant Saraca asoca

Leaf ontogeny of tropical evergreen tree species lasts several months with changes in size, shape, colouration and internal tissue distribution of leaves. Leaf initiation in Saraca asoca generally occurs once in a year during February–April, followed by very limited leafing thereafter. We measured the rate of photosynthesis, chlorophyll a fluorescence, energy quenching and PSII functions during the leaf ontogeny process. Observations were taken up to 35 days after opening of lamina (DAOL). Significant increase in the synthesis and accumulation of photosynthetic pigments but negative net photosynthesis was noticed during initial days of the ontogeny. The leaf moved from heterotrophy to autotrophy with gradual improvement of PSII functions. The ratio of intercellular CO2 (Ci) and ambient CO2 (Ca) showed significant change at ≥11 DAOL. Increase in the age of the leaf (between 5 and 28 DAOL) caused decrease in O-J rise and corresponding increase in J-I and I-P rise as well as of fluorescence maximum (FM) of the OJIP curve. The improvement of the electron transport components of the donor side of PSII was seen with increase in the functional oxygen evolving complex. The functional improvements of the donor and acceptor side of PSII during leaf ontogeny are discussed.

In vitro physiological and biochemical response of Stevia rebaudiana exposure to carbon nanotubes: Hormetic and photomixotrophic effect

Multi-walled carbon nanotubes (MWCNTs) are cylindrical rolled sheets with different applications in plant biotechnology due to their physicochemical characteristics. This study aimed to evaluate the in vitro physiological and biochemical responses of stevia (Stevia rebaudiana Bertoni) exposure to different concentrations of MWCNTs during multiplication phase in liquid medium using temporary immersion bioreactors. The MWCNTs were characterized regarding their properties by transmission electron microscope. Different treatments (0, 25, 50 and 100 mg/L) of MWCNTs were added to Murashige and Skoog semisolid culture medium at the proliferation phase. At 30 d of in vitro multiplication, the number of shoots, shoot length, number of leaves, dry matter, and antioxidant capacity were evaluated, as well as total chlorophyll, carotenoid, macro and micronutrient, phenolic, Phosphoenolpyruvate (PEP) and Rubisco contents. The results showed that adding MWCNTs at low doses (25 and 50 mg/L MWCNT) led to an increase in the in vitro multiplication rate and a higher number of leaves, while, at the highest dose (100 mg/L MWCNT), there was an inhibition of these variables. MWCNT treatments had an effect on Mg, Fe and C elements. The accumulation of photosynthetic pigments was associated with a higher PEP content in MWCNT treatments. Phenolic content increased at a concentration of 100 mg/L MWCNT, while antioxidant capacity increased at a concentration of 50 mg/L MWCNT. In conclusion, the usage of low MWCNT doses could be used to induce a hormetic response and to promote photosynthesis during in vitro propagation of stevia.

Variation in the Photosynthetic Leaf Pigments of Different Basil (Ocimum spp.) Genotypes under Varying Conditions at the Flowering Stage

Basil is a culinary herb in high demand all year round, either fresh, dried, or frozen. Field basil crops are commercially predominant, while greenhouse crops can cover the demand for fresh basil during the off-season. The leaf aspect of basil has great importance for the food industry, and a great diversity of genotypes has been created. The aim of this research was to conduct a comparative characterization of 12 basil genotypes (green and purple leaf) that present interest for breeding programs from a national germplasm collection. The study examines the accumulation of photosynthetic pigments in basil cultivated in field versus greenhouse conditions as indicators of plant performance and herb quality from the perspective of ensuring fresh plant material all year round. The experimental median indicated that photosynthetic leaf pigments accumulated in higher concentrations in the field relative to the greenhouse conditions, in descending order: β-carotene, lutein, chlorophyll a, and chlorophyll b. The trend was not as consistent for chlorophyll b, since four out of twelve genotypes presented higher levels in the greenhouse than in the field, while the overall values were not much lower in the greenhouse than the field (16.82%). All genotypes accumulated much higher carotenoid contents in field conditions relative to greenhouse conditions (>200%) and could also provide better nutritional advantages given their demonstrated health benefits. The differences in photosynthetic leaf pigments have both nutritional (the carotenoids), shelf-life, and processing relevance (chlorophylls) and serve as quality markers.

Enhancing french basil growth through synergistic Foliar treatment with copper nanoparticles and Spirulina sp.

BackgroundThis study investigates a novel idea about the foliar application of nanoparticles as nanofertilizer combined with a natural stimulant, blue-green algae Spirulina platensis L. extract, as a bio-fertilizer to achieve safety from using nanoparticles for enhancement of the growth and production of the plant. Thus, this experiment aimed to chemically synthesize copper nanoparticles via copper sulfate in addition to evaluate the impact of CuNPs at 500, 1000, and 1500 mg/L and the combination of CuNPs with or without microalgae extract at 0.5, 1, and 1.5 g/L on the morphological parameters, photosynthetic pigments accumulation, essential oil production, and antioxidant activity of French basil.ResultsThe results revealed that foliar application of CuNPs and its interaction with spirulina extract significantly increased growth and yield compared with control, the treatments of 1000 and 1500 mg/L had less impact than 500 mg/L CuNPs. Plants treated with 500 mg/L CuNPs and 1.5 g/L spirulina extract showed the best growth and oil production, as well as the highest accumulation of chlorophylls and carotenoids. The application of CuNPs nanofertilizer caused a significant increase in the antioxidant activity of the French basil plant, but the combination of CuNPs with spirulina extract caused a decrease in antioxidant activity.ConculosionTherefore, foliar application of natural bio-fertilizer with CuNPsis necessary for obtaining the best growth and highest oil production from the French basil plant with the least damage to the plant and the environment.

Growth, Physiological, and Biochemical Responses of a Medicinal Plant Launaea sarmentosa to Salinity

Launaea sarmentosa is a valuable medicinal plant with adaptability in saline areas, but it is still unclear how it responds to salinity. For the first time, the present study examined the plant’s changes under different soil salinities generated by 50, 100, 200, and 400 mM NaCl in order to elucidate its responses in terms of growth, photosynthesis, water uptake, osmotic adjustment, ion homeostasis, and oxidative stress defense to salinity. The results showed that the plant’s growth was enhanced by 50 mM NaCl with an 18.07% increase in dry biomass compared to the control, whereas higher salinity levels reduced its growth with a 6.39–54.85% decrease in dry biomass. The plant’s growth response indicates that it had tolerance to salinity levels up to 400 mM NaCl. The accumulation of photosynthetic pigments, including chlorophylls (a + b) and carotenoids, was enhanced under salinity, except for a reduced accumulation under 400 mM NaCl. Relative water content decreased while proline content increased in the salt-stressed plants. Moreover, the salt-stressed plants reduced their K+ and NO3− content along with increases in Na+ and Cl− content. The high salt stress level also caused oxidative stress in the plants, which was revealed through the accumulation of malondialdehyde and hydrogen peroxide content. In addition, the salt-stressed plants had increased total phenolic content and the activities of antioxidant enzymes such as catalase, peroxidase, and superoxide dismutase. These physiological and biochemical changes suggest that L. sarmentosa evolved adaptive mechanisms in photosynthesis, osmotic adjustment, ion homeostasis, and antioxidant defense for growing under salt stress.

Seasonal dynamics of photosynthetic pigments (chlorophylls a, b and carotenoids) in woody plants of the Altai Botanical Garden

This article reflects the results of studies of photosynthetic pigments (chlorophylls a, b and carotenoids) in 14 species of deciduous plants (trees and shrubs) and one coniferous Juniperus sabina L. in the Altai Botanical Garden during two growing seasons. The following species have a high accumulation of pigments: Acer tataricum L., Juglans cinerea L., Tilia cordata L., Corylus avellana L., Cotoneaster lucidus Schlecht., Lonicera tatarica L. For the coniferous species Juniperus sabina L. low levels of chlorophylls a, b and carotenoids are characteristic. Berberis thunbergii DC is also distinguished by a low accumulation of photosynthetic pigments. Minor differences between the species were noted in the content of carotenoids, twelve species were included in the group with low and medium content of this pigment. There is no definite pattern in the accumulation of carotenoids, and the data on the types and number of yellow pigments do not differ significantly. As a result of the conducted studies, a correlation was revealed between the content of carotenoids and the content of chlorophyll a in most species. The data obtained indicate the presence of species specificity in the content of chlorophylls a, b and carotenoids. Also, the photosynthetic apparatus of woody plants is sensitive to light and water conditions

Peculiarities of biochemical and mineral composition of lettuce <i>Lactuca sativa</i> L. grown from seeds after long-term storage in the International Space Station

Seed storage of agricultural crops in the conditions of International Space Station (ISS) is an effective method of quick plant breeding aimed to enhance the adaptability, and improve the biologically active compound accumulation and crop yield. Biochemical and mineral composition (ICP-MS) of lettuce grown in greenhouse from seeds stored for one year at the ISS was assessed. High varietal differences in lettuce tolerance to the effect of micro-gravity and radiation were evaluated using the values of yield, biometrical parameters, antioxidant status and plant mineral composition. Among the cultivars studied, i.e. Petrovich, Synthesis, Moskovsky parnikovy, Picnic, Cavalier and Bouquet, only the cvs. Retrovich, Synthesis, Moskovsky parnikovy and Picnik retained seed viability. Significant yield increase was recorded for the cv. Moskovsky parnikovy, while the cvs. Petrovich, Synthesis and Picnic demonstrated a tendency to the yield decrease. Improvement of photosynthetic pigment accumulation due to seed space storage was recorded for the cv. Moskovsky parnikovy and, particularly, the latter cultivar differed from the other cvs. due to the significantly higher proline level and lower MDA levels in leaves. Though space stress did not cause any significant decrease in antioxidant accumulation of plants, the latter demonstrated valuable changes in mineral composition. Among the 23 elements tested, V, Se. Fe and Cr showed higher concentrations compared to those in the control plants. Positive correlations between Ca, Sr, Cd, Cp, Mg, Mo and Pb were recorded (r > 0.9; p < 0.001).

Seasonal dynamics of photosynthetic pigments (chlorophylls a, b and carotenoids) in woody plants of the Altai Botanical Garden

This article reflects the results of studies of photosynthetic pigments (chlorophylls a, b and carotenoids) in 14 species of deciduous plants (trees and shrubs) and one coniferous Juniperus sabina L. in the Altai Botanical Garden during two growing seasons. The following species have a high accumulation of pigments: Acer ta-taricum L., Juglans cinerea L., Tilia cordata L., Corylus avellana L., Cotoneaster lucidus Schlecht., Lonicera tatarica L. For the coniferous species Juniperus sabina L. low levels of chlorophylls a, b and carotenoids are characteristic. Berberis thunbergii DC is also distinguished by a low accumulation of photosynthetic pigments. Minor differences between the species were noted in the content of carotenoids, twelve species were included in the group with low and medium content of this pigment. There is no definite pattern in the accumulation of carotenoids, and the data on the types and number of yellow pigments do not differ significantly. As a result of the conducted studies, a correlation was revealed between the content of carotenoids and the content of chlorophyll a in most species. The data obtained indicate the presence of species specificity in the content of chlorophylls a, b and carotenoids. Also, the photosynthetic apparatus of woody plants is sensitive to light and water conditions.

Effects of chemical oxygen demand and chloramphenicol on attached microalgae growth: Physicochemical properties and microscopic mass transfer in biofilm

During the wastewater treatment and resource recovery process by attached microalgae, the chemical oxygen demand (COD) can cause biotic contamination in algal culture systems, which can be mitigated by adding an appropriate dosage of antibiotics. The transport of COD and additive antibiotic (chloramphenicol, CAP) in algal biofilms and their influence on algal physiology were studied. The results showed that COD (60 mg/L) affected key metabolic pathways, such as photosystem II and oxidative phosphorylation, improved biofilm autotrophic and heterotrophic metabolic intensities, increased nutrient demand, and promoted biomass accumulation by 55.9 %, which was the most suitable COD concentration for attached microalgae. CAP (5–10 mg/L) effectively stimulated photosynthetic pigment accumulation and nutrient utilization in pelagic microalgal cells. In conclusion, controlling the COD concentration (approximately 60 mg/L) in the medium and adding the appropriate CAP concentration (5–10 mg/L) are conducive to improving attached microalgal biomass production and resource recovery potential from wastewater.

Alleviation of cotton growth suppression caused by salinity through biochar is strongly linked to the microbial metabolic potential in saline-alkali soil

Biochar is a typical soil organic amendment; however, there is limited understanding of its impact on the metabolic characteristics of microorganisms in saline-alkaline soil microenvironment, as well as the advantages and disadvantages of plant-microorganism interactions. To elucidate the mechanisms underlying the impact of saline-alkali stress on cotton, a 6-month pot experiment was conducted, involving the sowing of cotton seedlings in saline-alkali soil. Three different biochar application levels were established: 0 % (C0), 1 % (C1), and 2 % (C2). Results indicated that biochar addition improved the biomass of cotton plants, especially under C2 treatment; the dry weight of cotton bolls were 8.15 times that of C0. Biochar application led to a rise in the accumulation of photosynthetic pigments by 8.30–51.89 % and carbohydrates by 7.4–10.7 times, respectively. Moreover, peroxidase (POD) activity, the content of glutathione (GSH), and ascorbic acid (ASA) were elevated by 23.97 %, 118.39 %, and 48.30 % under C2 treatment, respectively. Biochar caused a reduction in Na+ uptake by 8.21–39.47 %, relative electrical conductivity (REC) of plants, and improved K+/Na+ and Ca2+/Na+ ratio indicating that biochar alleviated salinity-caused growth reduction. Additionally, the application of biochar enhanced the absorption intensity of polysaccharide fingerprints in cotton leaves and roots. Two-factor co-occurrence analysis indicated that the key differential metabolites connected to several metabolic pathways were L-phenylalanine, piperidine, L-tryptophan, and allysine. Interestingly, biochar altered the metabolic characteristics of saline-alkali soil, especially related to the biosynthesis and metabolism of amino acids and purine metabolism. In conclusion, this study demonstrates that biochar may be advantageous in saline soil microenvironment; it has a favorable impact on how plants and soil microbial metabolism interact.

Integrated field application of T. viride, botanicals, and fungicides for managing early blight (Alternaria solani) and enhancement of plant growth, tuber nutritional quality, and potato yield

Early blight disease, incited by Alternaria solani, is the most deleterious foliar disease of potato and other solanaceous crops. Herein, to counter the early blight disease, T. viride (Tv), botanicals [neem (N) and garlic (G)], and fungicides [flusilazole (F) and kasugamycin (K)] in different combinations applied through tuber treatment (ST) and foliar spray (FS) were evaluated for disease suppression, germination percent, plant growth promotion, photosynthetic pigments, and yield components as well as the nutritional quality of tubers under field conditions during the 2018–2019 and 2019–2020 seasons. The results of two-year field experiments revealed that the combination of Tv+ F+ N (ST) + G+K (FS) efficiently suppressed the development of the early blight disease symptoms and recorded 21.63 and 18.37% disease severity (DS) as compared to untreated control, respectively at 30 days post-treatment (dpt). During the 2018–2019 seasons, potato tubers treated with Tv +F significantly increased tuber germination (97.78%), while Tv+ F+ N treated potato tubers exhibited 98.89% tuber germination during the 2019–2020 season. Additionally, the potato plants treated with the combination of Tv+ F+ N (ST) + G+K (FS) and challenge inoculated with A. solani positively increased plant growth promotion activities like shoot and root length, fresh and dry weight of shoot and root, number of branches/plant, and induced accumulation of photosynthetic pigments like chlorophyll-a, b, and total carotenoids content during both seasons. Furthermore, under A. solani inoculated conditions, treatment with Tv+ F+ N (ST) + G+K (FS) significantly increased all yield attributing traits and other parameters associated with tuber nutritional quality such as starch (1.79-and 1.68-fold, respectively), vitamin-C (1.51-and 1.58-fold, respectively), total nitrogen (1.31-and 1.33-fold, respectively), total phosphorus (1.53-and 1.60-fold, respectively), and total potassium content (1.42-and 1.45-fold, respectively) as compared to untreated control in both seasons. So, it can be concluded that among all the treatments, integrated treatment comprising of tuber treatment with T. viride, flusilazole, and neem extract + one foliar spray of garlic extract and kasugamycin was found very effective in reducing early blight disease, promoting the plant’s growth, and increasing the yield as well as nutritional quality of tubers in the field conditions. The inclusive results indicated that integrated application might be a sustainable and eco-friendly control strategy for potato growers to manage potato early blight and achieve higher yields and nutritional tubers.

Condicionamento de sementes com qualidade de luz e extrato de Cyperus rotundus L. modula a germinação e o crescimento inicial de plântulas de Moringa oleifera

Improving plant germination is essential to guarantee better quality seedlings. Thus, this research aimed to evaluate whether the seed priming with light quality (LIQ) and the aqueous extract of Cyperus rotundus (AEC) tuber could modulate the germination and initial growth of Moringa oleifera L. seedlings. The experimental design was a completely randomized in the 4x4 factorial scheme, composed of four LIQ conditions (white, blue, red, and distant red light) and four AEC concentrations (0, 25, 50 and 100%). Seed priming with red light reduced the average emergence time, while blue, red, and extreme red lights associated with 50% of aqueous extract of C. rotundus increased shoot initial length and photosynthetic pigment accumulation. Seed priming with blue light resulted in seedlings with a shorter final shoot length. However, application of 100% of aqueous extract of C. rotundus reversed this. The white light in combination with concentrations of 50 and 100% of AEC promoted a higher relative shoot growth rate of seedlings. The research revealed that seed priming with light quality and aqueous extracts of C. rotundus tubers modulates the germination and initial growth of M. oleifera seedlings. More work needs to be done to determine the responsible compounds in AEC that is responsible for priming growth as phytohormones.

Impact of Colored Shade Nets on Biomass Production, Essential Oil Composition and Orientin and Isoorientin Content in Lippia gracilis Schauer.

The objective of this study was to evaluate the effect of ChromatiNet on vegetative growth, total antioxidant capacity, phenolic and essential oils (EOs) composition of Lippia gracilis. The plants were cultivated under full sunlight, black, blue and red ChromatiNet. The flavonoid content and antioxidant capacity were quantified spectrophotometrically. The C-glycosylflavone isomers (orientin and isoorientin) were isolated and identified by conventional spectroscopic techniques and measured using high-performance liquid chromatography-diode array detection. The EO was analysed by gas chromatography and gas chromatography-mass spectrometry. Environment influenced growth, total antioxidant capacity and phytochemical levels. Shoot dry weight, thymol, carvacrol and (E)-caryophyllene were favoured under red and black ChromatiNet. Root growth, EOs, caryophyllene oxide, p-cymene, flavonoids, orientin and isoorientin were favoured in sunlight. Growth and accumulation of EOs, flavonoids and photosynthetic pigments increased under blue ChromatiNet. Therefore, Lippia gracilis plants have plasticity related to the spectral quality of light and it cultivate depends of the phytochemicals of interest.

Изменчивость биохимических признаков Pinus sylvestris (Pinaceae) при адаптации форм в условиях избыточного увлажнения

Conifers are characterized by a certain degree of individual variability in the content of stress metabolites, which can be caused by genotypic variations or divergence in the growth conditions of individual trees. The purpose of the study is to evaluate the variation of biochemical traits of Scots pine, which are different in the color of male strobilus, during adaptation to the conditions of constant excessive moisture in the soil of the northern taiga. The dynamics of metabolic parameters of Pinus sylvestris L. were investigated in shrubsphagnum pine stands on marshy upland soils at the mouth of the Northern Dvina River (northern taiga subzone). From July to November 2018, needle samples from shoots were collected from 10 pine trees of each of the male strobilus types, differentiated by color. The contents of photosynthetic pigments, anthocyanins, ascorbic acid, proline, water-soluble proteins, and pH were measured under laboratory conditions. The synthesis of chlorophyll in the needles in the current year of formation decreased in trees of both forms during the dry summer period. A favorable temperature in the autumn period could promote an extension of photosynthetic pigment accumulation, which might negatively affect tree preparation for overwintering. There were no significant differences between f. erythranthera Sanio and f. sulfuranthera Kozubow in the needle content of chlorophyll and carotenoids, anthocyanins, ascorbic acid, free proline, water-soluble proteins, or pH. The similarities in the adaptation of the trees to the constant excessive soil moisture in northern taiga conditions were revealed. The seasonal factor had a considerable impact on the dynamics of biochemical parameters. Ascorbic acid, proline, and anthocyanin were more actively accumulated in the needles throughout the summer due to the high air temperature, resulting in an increase in antioxidant activity and the development of protective mechanisms aimed at reducing oxidative stress. The increase in water-soluble protein content in needles from October to November is one of the cryoprotective mechanisms of the trees for the winter period. Individual differences in ascorbic acid and proline contents in yellow microspore-bearing pine needles at the establishment of minus temperatures in November were considerably higher than in red microspore-bearing pine needles. This is regarded as the norm of the reaction for different types of trees to the influence of negative temperatures. For citation: Tarkhanov S.N., Pinaevskaya E.A., Aganina Y.E., Pakhov A.S. Variability of Biochemical Properties During Adaptation of Pinus sylvestris (Pinaceae) Forms to Excessive Moisture Conditions. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 58–75. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-58-75

Zinc oxide nano-flowers improve the growth and propagation of mulberry cuttings grown under different irrigation regimes by mitigating drought-related complications and enhancing zinc uptake

Silkworm larvae mainly consume mulberry leaves; therefore, mulberry cultivation is important for the production of raw silk. Drought stress and micronutrient deficiency (Zn) are known to affect the propagation of mulberry cuttings. In this purview, the current investigation attempted to inspect the efficacy of different concentrations of zinc oxide nano-flower (ZnNFs) applied through both soil admixture and foliar spray on the propagation of mulberry cuttings grown under deficit irrigation regimes. The overall results demonstrated that the ZnNF-treated plant cuttings were well-adapted to drought stress and performed better in comparison to the control set. Out of the tested concentrations – ZnNF-10 (applied as 10 mg/kg soil and 10 ppm as foliar spray thrice) was found to be optimum, showing relatively better initial root establishment, the emergence of leaves, and survival and sprouting percentage. Further studies also confirmed an improvement in the accumulation of photosynthetic pigments, carbohydrates, and protein content even under extreme drought conditions. Most importantly, the ZnNF-10 treatment contributed to ROS detoxification and cell membrane protection by enhancing the pool of antioxidant enzymes. The study further demonstrated that ZnNF-10 application enhanced zinc content by 147.50%, 179.49%, and 171.99% in root, shoot, and leaves of the treated cuttings; thereby, improving the bioaccumulation factor of the plant parts. All of these interactive phenomena led to an increment in shoot height, biomass, leaf area, and leaf number of cuttings. These findings, therefore, indicated that ZnNFs can be developed as a promising nano-fertilizer for mulberry growth facilitating Zn uptake and mitigation of drought-induced complications.

Extraction and comparative study of seasonal antioxidant activity using Nostoc species isolated from Gali Ali Bag, Erbil.

Seasonal variation of water, antioxidant activities as algal pigments, total antioxidant activities, DPPH, total phenolic compound using three solvents, methanol, acetone, and diethyl ether, of two algal species, N. commune and N. muscarum, were assessed. They also determined the physio-chemical and bacteriological water characteristics at the Gali Ali Bag. A significant variation were observed with an obvious correlation in water quality parameters in different seasons, generally raised in summer and reduced in winter. The two algal species show a higher accumulation of photosynthetic and accessory pigments in spring and summer and a significant decrease in winter. Antioxidant capacity in both algal species was analyzed by a three-way ANOVA and Kruskal-Wallis test. However, the contents were significant for all solvents. Moreover, N. muscarum shows the highest capacity in winter and reduced in summer for DPPH; however, the opposite pattern shows by N. commune. Although the total phenolic content of N. commune recorded a significant relation, N. muscarum was non-significant. The Cyanophyta algae show prominent growth responses and antioxidant activities and are better adapted to changing climatic conditions. Due to their prompt responses, even to minor changes in the aquatic environment, they can be used as ecological indicators in freshwater ecosystems.

The Yield and Quality Formation of Wheat Induced by Exogenous Strigolactones in Drought Condition

Drought is one of the major disasters affecting wheat. The change of wheat yield and quality directly affects the global population diet health. In this study, Strigolactones (SL) were sprayed on the leaf surface to study the relationship between wheat photosynthesis, nitrogen transport and yield and quality formation, further clarifying the influence of Sl on the synergic formation of yield and quality. The results showed that Sl could promote the accumulation of photosynthetic pigments in leaves, reduce nitrogen content in aging leaves and improve nitrogen transport level, then promote the improvement of grain yield and quality, so as to provide a reference for the application of Sl in wheat stress-resistant cultivation.

Salinity-induced modulation of growth and accumulation of phytochemicals composition in in vitro root cultures of Azadirachta indica

Salinity is a destructive abiotic factor that negatively impacts the growth and development of stress-intolerant plants. Although the effect of salinity on the growth of Azadirachta indica (neem) under in vitro conditions has been widely studied, little is known about the biochemical properties of in vitro root cultures exposed to salinity stress. Therefore, this study aimed to investigate the effects of varying concentrations of salinity on the biochemical properties of A. indica root cultures, specifically on total pigment and phenolic contents, antioxidant activities, and the presence of phytochemicals and azadirachtin compound, at different incubation periods. The results demonstrated that the root cultures coped with increasing NaCl concentrations by altering their phenotype. The highest antioxidant potential was observed in root cultures grown on MSN media (Murashige and Skoog media containing 3 mg L−1 NAA) supplemented with 0.5% w/v NaCl for 4 weeks. Additionally, this media composition and incubation period also resulted in the highest total phenolic and anthocyanin contents. The accumulation of photosynthetic pigments significantly decreased when exposed to NaCl treatments after 4 and 8 weeks. Interestingly, short-term exposure to NaCl had a positive impact on the azadirachtin (AZA) content, while longer treatment duration significantly decreased it. The highest amount of AZA was quantified from root cultures elicited with 1.5% w/v NaCl for 4 weeks. These findings contribute to a better understanding of the effects of salinity stress on the biochemical properties of in vitro root cultures of A. indica. The findings can aid in the development of strategies to enhance the production of bioactive compounds with potential applications in the food and pharmaceutical industries. Additionally, the study provides insights into the physiological mechanisms and manipulation of secondary metabolite production associated with salt tolerance in A. indica and other related species.