Plant Photosynthetic Pigments Research Articles

Silicon and Seaweed Extract Injection into Olive Tree (Olea europaea L.) Trunks Results in the Tree’s Drought Stress Resistance

ABSTRACT Trunk injection applies more nutrients in the correct volume and composition, delivering ideal results with fewer fertilizer treatments under drought-stress conditions. We used a completely randomized block design to examine the effects of trunk injection therapy on the development of drought stress tolerance in olive trees in arid climates. Treatments included seaweed extract (SWE), potassium amino acid chelate (PAC), calcium silicate (CS), and potassium silicate (PS) at five different concentrations: 0.25, 0.5, 1, 2, and 4% for each treatment. Each treatment consisted of four replications – four dry replications for each treatment and four irrigation controls – each receiving weekly irrigation. The findings showed that, in comparison to drought control, trunk injection of PAC at a concentration of 2% enhances the relative water content of leaf and proline and decreases electrolyte leakage (EL) and malondialdehyde (MDA) content. Chlorophyll a, carotenoids, and proline content are all significantly higher in the trunk after CS injection at a 4% concentration than in the control treatment. MDA and EL were also reduced. Injecting PS leads to an increase in proline and photosynthetic pigments. The SWE treatment improved the proline, relative leaf water content, and photosynthetic pigments. To sum up, trunk injection treatments under drought conditions improved plant photosynthetic pigments, increased proline content, prevented relative water content reduction, and prevented an increase in MDA and EL. In conclusion, among the several treatments, the use of 2% PS was the most effective at reducing the adverse effects of drought stress on olive plants.

Вплив кліматичних умов на вміст та співвідношення фотосинтетичних пігментів у рослин роду Carlina L.

Вплив кліматичних умов на вміст та співвідношення фотосинтетичних пігментів у рослин роду Carlina L.

Opportunistic pathogenicity observed for the endophytic fungus Diaporthe ueckerae on Gossypium hirsutum plants

AbstractCotton crops are routinely threatened by emerging fungal diseases. Fungal endophytes also can be considered latent phytopathogens. In this study we tested the hypothesis that an endophytic strain of Diaporthe, isolated from chlorotic leaves of cotton (Gossypium hirsutum), could trigger physiological effects of biotic stress in this oilseed plant. We also assessed the histopathological aspects of the mycelial interaction of the endophyte with the adaxial surface of G. hirsutum leaves. Thus, we studied the synthesis of photosynthetic pigments, pattern of gas exchange, and photochemistry of cotton plants subjected to inoculation with Diaporthe ueckerae via root and leaf at three different phenological stages (vegetative, reproductive, and maturation). Additionally, we histopathologically analyzed infected leaves using electron microscopy to study the process of leaf colonization by this endophytic fungus. We evidenced that D. ueckerae inoculation negatively affected the synthesis of photosynthetic pigments in plants at vegetative and reproductive stages. Moreover, inoculation also negatively affected the photosynthetic rate and carboxylation efficiency of these plants. We also found that the presence of the endophyte increased transpiration and decreased water use efficiency in the plants. Furthermore, foliar inoculation negatively affected stomatal conductance, whereas inoculation via leaf or root reduced the photochemical performance of cotton. We also observed that D. ueckerae colonizes the leaf tissues of G. hirsutum via glandular trichomes and forces penetration into the epidermis using appressoria, and the plant responds by closing the stomata. The observed physiological alterations are indicative of biotic stress, confirming the hypothesis that D. ueckerae may be an opportunistic phytopathogen for cotton plants.

Promising Eco-Friendly Nanoparticles for Managing Bottom Rot Disease in Lettuce (Lactuca sativa var. longifolia)

Developing innovative, eco-friendly fungicide alternatives is crucial to mitigate the substantial threat fungal pathogens pose to crop yields. In this study, we assessed the in vitro effectiveness of SiO2, CuO, and γFe2O3 nanoparticles against Rhizoctonia solani. Furthermore, greenhouse experiments were conducted in artificially infested soil to evaluate the in vivo impact of nanoparticles under study. Two application methods were employed: soil drenching with 10 mL per pot at concentrations of 50, 100, and 200 mg L−1, and seedling dipping in nanoparticle suspensions at each concentration combined with soil drench. The combined treatment of 200 mg L−1 γFe2O3 or CuO nanoparticles showed the highest in vitro antifungal activity. Conversely, SiO2 nanoparticles demonstrated the lowest in vitro activity. Notably, the application of 200 mg/L SiO2 via the dipping and soil drenching methods decreased counts of silicate-solubilizing bacteria and Azospirillum spp. Whereas, application of 100 mg L−1 γFe2O3 nanoparticles via soil drenching increased soil bacterial counts, and CuO nanoparticles at 50 mg L−1 through dipping and soil drenching had the highest dehydrogenase value. γFe2O3 nanoparticles improved plant photosynthetic pigments, reduced malondialdehyde levels, and minimized membrane leakage in lettuce plants. A root anatomical study showed that 200 mg L−1 CuO nanoparticles induced toxicity, whereas 200 mg L−1 γFe2O3 or SiO2 nanoparticles positively affected root diameter, tissue structure, and various anatomical measurements in lettuce roots. γFe2O3 nanoparticles hold promise as a sustainable alternative for managing crop diseases.

Impact of anionic synthetic surfactants of lead ions and their combinations on the pigment profile of freshwater plant organisms Ceratophyllum demersum and Egeria densa

The development of human civilization inevitably leads to the development of production with increasing emissions of many chemicals into the environment. This is especially noticeable in relation to surface waters of fresh water bodies. A very alarming point is that the amount of toxic anthropogenic substances, including heavy metals, is growing every year and is increasingly disturbing the existing ecological balance. Plant organisms of water bodies are among the first to experience the effects of any anthropogenic pollutants and especially heavy metals and surfactants, the amount of which increases in the water of rivers and lakes. Very important in this is the complex of morpho-physiological adaptations associated with restructuring in the structure of chloroplasts. Changes in the content of photosynthetic pigments in plants of two species (Ceratophyllum demersum and Egeria densa) were assessed when they were exposed to very common technogenic substances (lead ions and a solution of anionic synthetic surfactants). In plants, there is a decrease in the activity of molecular transport, inhibition of H+-ATPase, leading to a decrease in the pH of the cytoplasm and activation of hydrolases, which enhance the breakdown of biopolymers. This leads to changes in the expression of individual genes and increased synthesis of a number of stress proteins. Under these conditions, the assembly of cytoskeletal elements is activated, the structures of membrane proteins and lipids change, the level of ATP decreases, free radical processes are activated and the intensity of photosynthesis is inhibited.

The influence of polyguanidin on the direction of biochemical processes in wheat (Triti- cum L.) plants.

Modern crop production requires a balance of high and sustainable productivity with maximum safety for the environment, consumers and agricultural workers. The well-known chemical compound polyguanidine, which was previously used as a disinfectant, surfactant and complexing agent, has recently become widely used as a plant growth and development stimulant. Despite the increasing use of polyguanidine preparations as a growth stimulant, there is no data in the literature on its mechanism of action on plants. There are many studies that try to determine whether the effect of biostimulants on plant productivity is a direct or indirect response, for example, through the soil or microbiome. In many cases, biostimulants are considered in terms of their effects on various plant regulatory and functional systems (signaling, metabolic, uptake and transport mechanisms, etc.). But, in general, these modes of action are very diverse and may include activation of nitrogen metabolism or release of phosphorus from soils, general stimulation of soil microbial activity, or stimulation of root growth and increased plant nutrition. The effect of polyguanidin on the physiological parameters of wheat plants was studied under vegetation and laboratory conditions. Seeds of winter wheat variety Bogdana were used for the study. For the determination of flavonoids, a spectrophotometric method based on the measurement of their absorption with aluminum chloride complex was used. It was proved that the treatment of wheat in the tillering and earing phases with polyguanidin had the greatest effect on the protein content in winter wheat grain, which ensured the formation of this indicator at the level of 11.0–13.4% compared to the control. The treatment of wheat seeds with a preparation based on polyguanidine increased the amount of chlorophyll a by almost two times, while the content of chlorophyll b and carotene increased somewhat less. Thus, the use of polyguanidine contributes to the efficient functioning of the photosynthetic apparatus of plants, which will increase their productivity. Since the energy basis of photosynthesis is the absorption of solar radiation by photosynthetic pigments, which are used to form organic matter, there is a direct link between chlorophyll content and plant productivity. Therefore, we decided to check the content of the main photosynthetic pigments in plants after treatment with polyguanidine. At the first stage of our research, plants at the early stages of ontogenesis were analyzed. Thus, we have shown that the treatment of wheat seeds with a polyguanidine-based preparation increases the amount of chlorophyll a almost twice. Evaluation of flavonoid content in wheat plants showed a decrease in their amount after treatment with polyguanidin. That is, after the treatment, the plants, on the contrary, reduced their adaptive potential, because at the biochemical stage it was believed that there were no unfavorable factors in the environment. The analysis of the free proline content showed an increase in its concentration after treatment with the test substance almost doubled both after the first and after the second treatment. Also, it should be noted that reducing the concentration of the drug to 0.15 liters per 200 liters of the working solution increases the level of proline after the first treatment. The increase in proline, in this case, can lead to an increase in stress resistance, which is provided by metabolic and physiological changes. Consequently, its accumulation and conversion into other amino acids due to changes in the activity of proline oxidase contributes to an increase in the protein content in the grain.

Far-Red Light Mediated Carbohydrate Concentration Changes in Leaves of Sweet Basil, a Stachyose Translocating Plant.

Photosynthetic active radiation (PAR) refers to photons between 400 and 700 nm. These photons drive photosynthesis, providing carbohydrates for plant metabolism and development. Far-red radiation (FR, 701-750 nm) is excluded in this definition because no FR is absorbed by the plant photosynthetic pigments. However, including FR in the light spectrum provides substantial benefits for biomass production and resource-use efficiency. We investigated the effects of continuous FR addition and end-of-day additional FR to a broad white light spectrum (BW) on carbohydrate concentrations in the top and bottom leaves of sweet basil (Ocimum basilicum L.), a species that produces the raffinose family oligosaccharides raffinose and stachyose and preferentially uses the latter as transport sugar. Glucose, fructose, sucrose, raffinose, and starch concentrations increased significantly in top and bottom leaves with the addition of FR light. The increased carbohydrate pools under FR light treatments are associated with more efficient stachyose production and potentially improved phloem loading through increased sucrose homeostasis in intermediary cells. The combination of a high biomass yield, increased resource-use efficiency, and increased carbohydrate concentration in leaves in response to the addition of FR light offers opportunities for commercial plant production in controlled growth environments.

Purpureocillium lilacinum for plant growth promotion and biocontrol against root-knot nematodes infecting eggplant.

Purpureocillium lilacinum is a biocontrol Ascomycota fungus against various plant pathogens. In the present study, the efficacy of P. lilacinum was evaluated against a root-knot nematode, Meloidogyne incognita that infects eggplants. We performed an in vitro experiment in which the direct effects of P. lilacinum on the second-stage juvenile survival and egg hatching of M. incognita were tested at different exposure times. The results showed that P. lilacinum significantly reduced the rates of egg hatching and juvenile survival in a dose-dependent manner. Microscopic observation demonstrated that P. lilacinum directly penetrated the eggs and contacted the juveniles, indicating how P. lilacinum parasitizes M. incognita. We also performed a pot assay in which soil-grown eggplants were treated with P. lilacinum followed by inoculation with M. incognita. The results indicated that P. lilacinum effectively reduced the nematode population and the number of galls in plant roots. Interestingly, application of P. lilacinum resulted in significant enhancements in plant growth and biomass, even under nematode infection, while it improved plant photosynthetic pigments, i.e., chlorophyll and carotenoids. Taken together, our study suggested that P. lilacinum can be used as a plant growth-promoting fungus and a biological nematicide for disease management of root-knot nematodes in eggplants.

Ecological health risk assessment of microplastics and heavy metals in sediments, water, hydrophytes (Alternanthera philoxeroides, Typha latifolia, and Ipomoea carnea), and fish (Labeo rohita) in Marala wetlands in Sialkot, Pakistan.

For the ecological risk assessment of heavy metals and microplastics in Marala wetlands in Sialkot, Pakistan, samples of sediments, water, aquatic plants (Alternanthera philoxeroides, Typha latifolia, and Ipomoea carnea), and fish (Labeo rohita) were studied from five different locations. Pb, Cd, and Cr concentrations were above permissible limits devised by WHO in sediments and water at most of sites. High concentrations of Cd were recorded in water samples compared to sediments with maximum values recorded at Site-2 (52.08 ± 9.55mgkg-1) and Site-5 (62.29 ± 10.12mgkg-1). The maximum concentrations of Cr (7.23 ± 0.40mgkg-1) and Pb (22.87 ± 0.83mgkg-1) were found at Site-4 in water samples. The maximum abundance of microplastics (3047 pieces kg-1 of sediments) was at Site-1 with filaments in the highest proportion among the other types. Zn, Ni, and Cu remained generally low in concentrations in both sediments and waters. Plants showed accumulation of heavy metals, notably the amount of Cd (33.36 ± 0.26 mgkg-1) and Ni (163.3 ± 1.30 mgkg-1) absorbed by T. latifolia and A. philoxeroides, respectively were high. Also, photosynthetic pigments in plants seemed to be affected. However, estimated daily intake (EDI) and provisional tolerable weekly intake (PTWI) calculations for the human population consuming fish from this wetland remained below the FAO/WHO limits. PCA analysis revealed the anthropogenic origin of metals that might be causing adverse effects on the biota which depend on this wetland for their food.

The influence of lead ions, cationic synthetic surfactants and their combinations on the pigment composition of tissues of plant organisms in water bodies Ceratophyllum demersum and Egeria densa

The mass of man-made chemical elements entering water bodies along with wastewater is gradually increasing, causing a lot of negative consequences. Plant organisms of water bodies are among the first to experience the effects of any anthropogenic pollutants and especially heavy metals and surfactants, the amount of which increases in the water of rivers and lakes. Changes in the ratio of the pool of green and yellow enzymes in aquatic plants are considered as a reliable diagnostic indicator of the development of disorders in plant cells due to technogenic influences. Changes in the content of photosynthetic pigments in plants of two species (Ceratophyllum demersum and Egeria densa) were monitored when they were exposed to very common technogenic substances (lead ions and a solution of cationic synthetic surfactants). The changes found in the quantitative content of photosynthetic pigments in aquatic plants are caused by the appearance and development of stress and some adaptation to it. Under these conditions, the structures of proteins and lipids of thylakoid membranes change, the level of ATP decreases, free radical processes are activated and the intensity of photosynthesis is inhibited. Thus, the action of lead ions, a solution of cationic synthetic surfactants, and especially their combination have a very negative effect on the tissues of Ceratophyllum demersum and Egeria densa, which is expressed in a change in the content of photosynthetic pigments and their ratio.

Role of foliar spray of plant growth regulators in improving photosynthetic pigments and metabolites in Plantago ovata (Psyllium) under salt stress–A field appraisal

Salinity is one of the major abiotic factors that limit the growth and productivity of plants. Foliar application of plant growth regulators (PGRs) may help plants ameliorate the negative impacts of salinity. Thus, a field experiment was conducted at the Botanical Garden University of Balochistan, Quetta, to explore the potential role of PGRs, i.e., moringa leaf extract (MLE; 10%), proline (PRO; 1 µM), salicylic acid (SA; 250 µM), and thiourea (TU; 10 mM) in ameliorating the impacts of salinity (120 mM) on Plantago ovata, an important medicinal plant. Salinity hampered plant photosynthetic pigments and metabolites but elevated oxidative parameters. However, foliar application of PGRs enhanced photosynthetic pigments, including Chl b (21.11%), carotenoids (57.87%) except Chl a, activated the defense mechanisms by restoring and enhancing the metabolites, i.e., soluble sugars (49.68%), soluble phenolics (33.34%), and proline (31.47%), significantly under salinity stress. Furthermore, foliar supplementation of PGRs under salt stress led to a decrease of about 43.02% and 43.27% in hydrogen peroxide and malondialdehyde content, respectively. Thus, PGRs can be recommended for improved photosynthetic efficiency and metabolite content that can help to get better yield under salt stress, with the best and most effective treatments being those of PRO and MLE to predominately ameliorate the harsh impacts of salinity.

Composition of pigment complex in leaves of soybean plants, inoculated by Bradyrhizobium japonicum, subject to metal nanocarboxylates and various-levels of water supply

A distinctive feature of legumes is the ability to combine two most important processes: photosynthesis and nitrogen fixation. However, the course of those processes, and therefore seed potential of those crops depend on a number of biotic and abiotic factors, the commonest being drought. Therefore, interest in physical-biochemical resistance of the plant organism to abiotic stress factors is increasing, as well as search for optimum ways to increase its adaptability. Success of adaptation of a plant’s organism to unfavourable environmental factors is known to largely depend on optimal functioning of assimilative apparatus. Some indicators of the condition of the apparatus are the content and ratio of photosynthesis pigments. Therefore, we aimed at determining the reaction of the pigment complex of Glycine max (L.) Merr. plants, grown against the background of optimal and insufficient watering, to inoculation of seeds with rhizobia bacteria Bradyrhizobium japonicum, cultivated using nanocarboxylates of chromium, cobalt, iron, copper and germanium. Research has shown that utilization of germanium nanocarboxylate as a component of inoculative suspension led to the highest content of chlorophylls in leaves of soybean of the studied variants in the blossoming phase during optimal watering, as well as significant increase in the content of carotenoids compared with the control plants regardless of the level of watering. At the same time, this element caused no significant effect on the chlorophyll content in plants grown in drought. It was confirmed that among soybean plants that were in stress conditions (blossoming phase) for two weeks, the highest content of chlorophylls was in leaves of plants grown from seeds inoculated with rhizobial suspension with addition of chromium and copper nanocarboxylates, which caused 25.3% and 22.8% increase in chlorophyll а, 29.4% and 32.3% in chlorophyll b and 26.4%% and 23.8% in them respectively, compared with the control. Furthermore, chromium and copper nanocarboxylates stimulated the content of carotenoids in the same plants, though it was less expressed than after adding germanium nanocarboxylate. The highest content of photosynthetic pigments in plants after the watering was resumed (phase of bean formation) was in cases of applying chromium and germanium nanocarboxylates. It was confirmed that the most efficient way to protect the pigment complex of soybean plants during drought was using chromium and germanium nanocarboxylates as components of inoculation suspension. The results we obtained indicate the possibility of applying chromium nanocarboxylate in the technology of cultivating soybean in the conditions of water deficiency as an effective way to improve biosynthesis of chlorophylls, as well as using germanium nanocarboxyllate as a component that provides a high level of activity of protective mechanisms of the pigment system of soybean, associated with resisting stress caused by water deficiency.

The impact of Salt Stress on The Growth and Photosynthetic Pigments of Vicia faba (L).

Water used for crop irrigation is often of insufficient quality in the Mediterranean region, where sea water invades the porous karst matrix and salinizes Sources of soil and water. Measuring the productivity of horticultural crops under saline conditions helps decide if and when crops should be irrigated if water is saline, thus balancing crop water and salt stress. To examine the effects of saline irrigation water on (Vicia faba L.) biomass and yield parameters, a greenhouse pot experiment was set up.NaCl salinity was applied as follows: After 15 days from irrigation, plants were subjected to graded levels of salinity: 0, 50, 100, 200 and 300 mM NaCl, applied in stepwise daily increments to avoid induction of salt shock to the seedlings. Height of Plant (cm), The number of lateral branches , number of( leaves, pods, seeds) per plant, shoot weight (g), is correlated with an increase in stressed plant photosynthetic pigments. five weeks after salinity therapy, the weight of the pod (g) and the weight of the seed (g) were determined. Increased irrigation water salinity statistically significantly decreased the calculated parameters (P<0.05) relative to regulation , except for the number of branches and pods. Salinity is associated with an increase in photosynthetic pigments in stressed plants. The productivity of Vicia faba has decreased in proportion to the degree of salinity of irrigation water.

Non-destructive Photosynthetic Pigments Prediction using Multispectral Imagery and 2D-CNN

Rapid assessment of plant photosynthetic pigments content is an essential issue in precise management farming. Such an assessment can represent the status of plants in their stages of growth. We have developed a new 2 Dimensional-Convolutional Neural Network (2D-CNN) architecture, the P3MNet. This architecture simultaneously predicts the content of 3 main photosynthetic pigments of a plant leaf in a non-destructive and real-time manner using multispectral images. Those pigments are chlorophyll, carotenoid, and anthocyanin. By illuminating with visible light, the reflectance of individual plant leaf at 10 different wavelengths – 350, 400, 450, 500, 550, 600, 650, 700, 750, and 800 nm – was captured in a form of 10 digital images. It was then used as the 2D-CNN input. Here, our result suggested that P3MNet outperformed AlexNet and VGG-9. After undergoing a training process using Adadelta optimization method for 1000 epochs, P3MNet has achieved superior MAE (Mean Absolute Error) in the average of 0.000778 ± 0.0001 for training and 0.000817 ± 0.0007 for validation (data range 0-1).

Unlocking the potential plant growth‐promoting properties of chickpea (Cicer arietinum L.) seed endophytes bio‐inoculants for improving soil health and crop production

AbstractSustainable agronomic practices are tried all over the world to promote safe and eco‐friendly crop production. Therefore, in the present study, the effect of seed endophytic bacteria and its consortium on soil biochemical property and yield of chickpea (Cicer arietinum L.) under field and pot conditions are investigated. Both the experimental results proved a significant increase in total soil organic carbon (OC), electric conductivity (EC), organic matter (OM), and soil nutrients like available N, P, and K content and important soil enzymes like dehydrogenase (DHA), beta glucosidase, alkaline phosphate, urease, and microbial population in soil was observed under the Enterobacter hormaechei BHUJPCS‐15 (T1), Enterobacter cloacae BHUJPCS‐21 (T2), and combined T3 (consortium of T1 and T2) treatments. Similarly, a significant increase in the grain yield (27–45% and 57–73%) in microbial treatment was found in pot and field experiments, respectively, than in control. In addition, whereas the higher plant biomass (14–38% and 42–78%) was recorded in treated plant over the control plant. Similarly, the plant photosynthetic pigments (Chl a, b, total Chl) were increased in microbial treated plant than the control untreated chickpea plant. Consortium of endophytes were recorded effective result for enhancing plant growth attributes, productivity, and soil health. The consortium can be further used as biofertilizers for sustainable chickpea production. Our present study highlights the significance of sustainable agronomic practices for improving the soil quality and agricultural yield while reducing adverse impacts of chemicals by the use of seed endophytic microbes and its consortium.

Effect of sewage sludge application on growth and photosynthetic pigments in vetiver grass (<em>Vetiveria zizanioides</em> L. Nash)

The study was conducted to evaluate the effect of sewage sludge application on growth and photosynthetic pigments in vetiver grass. Vetiver plants were grown in poly-ethylene U-V stabilized grow bags (24 X 24 X 40) for a period of three months (90 days), where the soil treated with different sewage sludge concentrations (0, 25, 50 and 75%). Physico-chemical characterization of sewage sludge showed that it was slightly acidic with significant concentrations of heavy metals (Cd, Cr, Cu, Pb and Zn), nutrients and mineral ions. Results showed that there were no apparent symptoms of toxicity on the morphology (leaf color, plant height and number of leaves) of the sludge amended vetiver plants. It has been observed that 25% sludge concentration has a favorable effect on the growth and photosynthetic pigments of plants. But at 50 and 75% sludge concentration, photosynthetic pigments such as chlorophylls and Pheophytin content showed a gradual decline with increase in sludge concentration while the carotenoid content was increased gradually. Even though compared to control plants sludge amendment increased the total wet biomass production in all the experimental plants with a gradual increase with increase in sludge concentration. This study proves that use of sewage sludge as an amendment will improve the growth and biomass production in vetiver plants up to 25% of the total soil. But even at this concentration carotenoid content was high and it may be due to defense mechanisms induced in response to heavy metal stress. The study, therefore, suggests that even though the sewage sludge is highly enriched with various nutrients, considering the heavy metal content, the fertilizer application of sewage sludge is dangerous, because the risk of environmental contamination is very high. The study pointed out that the vetiver plants growing in sludge amended area have potentially developed the defense strategy to combat against heavy metal toxicity. Therefore, the highly tolerant vetiver plants (Vetiveria zizanioides, L. Nash) may be used for phytoremediation purposes.

Priming with salicylic acid, β-carotene and tryptophan modulates growth, phenolics and essential oil components of Ocimum basilicum L. grown under salinity

Stress tolerance of the plant can be enhanced with the used of compounds that exhibit remarkable abilities to improve the growth without any side effects on plants and its environment. Many physiological and molecular activities in plants are controlled with those compounds. Of the medicinal and aromatic plants, sweet basil (Ocimum basilicum) possesses economic value due to their secondary metabolites such as essential oil and phenolic compounds. Along with the study, it was aimed to decrease the adverse impacts of the salinity stress from NaCl can be alleviated using priming with compounds. Herewith the study, salicylic acid, tryptophan and β-carotene were used for seed priming. Briefly, seeds of basil were soaked into 0.025 and 0.05 mM salicylic acid, 0.25 and 1 mM tryptophan and 0.1 and 0.2 mM β-carotene for 24 h. Following seed priming, when plants reached 5–6 leaf stage, the plants were exposed to salt stress (100 mM NaCl). In this context, plant growth parameters, photosynthetic pigments, essential oil components, total phenolic contents with their major fractions and DPPH activities of the plant leaves were screened. Results indicated that salinity decreased shoot and root length, root and leaf weight, leaf number, plant weight, and photosynthetic pigments of the plants. However, priming treatments partially alleviated the adverse effects of salinity on shoot and root length, root, leaf and plant weight, but had no significant effects on photosynthetic pigments in plants grown under saline conditions. Of the essential oil components, salinity reduced the percentage of linalool and eugenol but increased methyl eugenol percentage in non-primed plants. However, priming increased percentage of linalool and eugenol but decreased methyl eugenol percentage in plants grown under saline conditions. Regarding phenolics and individual fractions, salinity caused significant reductions in total phenolic, flavonoid contents, caffeic acid, chicoric acid, and rosmarinic acid content. Furthermore, DPPH activities of the extracts were also negatively affected by salinity. In addition, gas exchange parameters such as assimilation rate and stomatal conductance were affected negatively by salinity. Though, priming had a positive contribution to the gas exchange parameters under saline and non-saline conditions. As a result, it was observed that basil seedlings were negatively affected in terms of yield in 100 mM salt application, but especially 1 mM tryptophan priming could protect plants from the toxic effect of salt and increase the amount of individual phenolics under stress.

Dependence of the content of photosynthetic pigments in plants of certain species of the genus Carlina L. from in vitro lighting conditions

Dependence of the content of photosynthetic pigments in plants of certain species of the genus Carlina L. from in vitro lighting conditions

Real-time assessment of plant photosynthetic pigment contents with an artificial intelligence approach in a mobile application

The assessment of the photosynthetic pigment contents in plants is a common procedure in agricultural studies and can describe plant conditions, such as their nutritional status, response to environmental changes, senescence, disease status and so forth. In this report, we show how the photosynthetic pigment contents in plant leaves can be predicted non-destructively and in real-time with an artificial intelligence approach. Using a convolutional neural network (CNN) model that was embedded in an Androidbased mobile application, a digital image of a leaf was processed to predict the three main photosynthetic pigment contents: chlorophyll, carotenoid and anthocyanin. The data representation, low sample size handling and developmental strategies of the best CNN model are discussed in this report. Our CNN model, photosynthetic pigment prediction network (P3Net), could accurately predict the chlorophyll, carotenoid and anthocyanin contents simultaneously. The prediction error for anthocyanin was ±2.93 mg/g (in the range of 0-345.45 mg/g), that for carotenoid was ±2.14 mg/g (in the range of 0-211.30 mg/g) and that for chlorophyll was ±5.75 mg/g (in the range of 0-892.25 mg/g). This is a promising result as a baseline for the future development of IoT smart devices in precision agriculture.

Nondestructive analysis of photosynthetic pigments in forage radish and vetch

Chlorophylls and carotenoids are the main photosynthetic pigments in plants, and photosynthetic potential can be used to determine the nitrogen fixation or cycling capacity of cover crops. Therefore, this study quantified and compared the content of photosynthetic pigments in Raphanus sativus and Vicia sativa by using two different methods, namely the extraction method and measurements with a portable chlorophyll meter, and determined whether the results of these two methods showed a significant correlation. Photosynthetic pigments were measured, using both methods, in a greenhouse and laboratory, at four developmental stages: the vegetative stages I (30 days after sowing [DAS]), II (60DAS), and III (90DAS), and the reproductive stage (150DAS). The determination of the photosynthetic pigment content in R. sativus and V. sativa, obtained from the extraction method and chlorophyll index, revealed significant differences depending on the developmental stage in both species. Furthermore, the contents of chlorophyll a, chlorophyll b, and carotenoids determined using the extraction method showed high coefficients of correlation with the total chlorophyll index determined using the portable chlorophyll meter. Therefore, the portable chlorophyll meter can be used for the accurate evaluation of the photosynthetic potential of Raphanus sativus and Vicia sativa, which also saves time and reagents.