Pigment Content Research Articles

Molecular, Metabolic, and Physiological Responses to Progressive Biotic Stress Caused by Cucumber Mosaic Virus and Turnip Mosaic Virus in Saffron

The economic value of the saffron stigma is primarily due to three crucial apocarotenoids: crocin, picrocrocin, and safranal, which contribute to its color, flavor, and aroma. These compounds make saffron highly valuable in various industries. Plant viruses like the cucumber mosaic virus (CMV) and turnip mosaic virus (TuMV) are significant threats to agricultural crops worldwide, causing economic losses. To elucidate the influence of viral stress on the quality of saffron, morphological, physiological, biochemical, and molecular indexes were assessed. Under the stress of both viruses, typical viral symptoms appeared. The lowest contents of leaf pigments, flowering performance, petal anthocyanin, greenness, and photosynthesis properties were observed in plants infected with CMV and TuMV. According to high-performance liquid chromatography (HPLC) analysis, CMV inoculation led to the highest reduction in crocin and safranal content, while inducing the highest increase in picrocrocin compared to the mock treatment. Gene expression analysis involved in the biosynthesis of crucial secondary metabolites showed a high correlation with the content of each metabolite. CMV inoculation resulted in the lowest expression of CsALDH31l and the highest expression of CsUGT709G1 compared with the mock treatment. Our findings demonstrate the association between virus stress and changes in the metabolism of the saffron medicinal plant.

Nano-Zinc Oxide Can Enhance the Tolerance of Apple Rootstock M9-T337 Seedlings to Saline Alkali Stress by Initiating a Variety of Physiological and Biochemical Pathways

Soil salinization severely restricts the growth and development of crops globally, especially in the northwest Loess Plateau, where apples constitute a pillar industry. Nanomaterials, leveraging their unique properties, can facilitate the transport of nutrients to crops, thereby enhancing plant growth and development under stress conditions. To investigate the effects of nano zinc oxide (ZnO NP) on the growth and physiological characteristics of apple self-rooted rootstock M9-T337 seedlings under saline alkali stress, one-year-old M9-T337 seedlings were used as experimental materials and ZnO NPs were used as donors for pot experiment. Six treatments were set up: CK (normal growth), SA (saline alkali stress,100 mmol/L NaCl + NaHCO3), T1 (saline alkali stress + 50 mg/L ZnO NPs), T2 (saline alkali stress + 100 mg/L ZnO NPs), T3 (saline alkali stress + 150 mg/L ZnO NPs) and T4 (saline alkali stress + 200 mg/L ZnO NPs). The results were found to show that saline alkali stress could significantly inhibit the growth and development of M9-T337 seedlings, reduce photosynthetic characteristics, and cause ion accumulation to trigger osmotic regulation system, endogenous hormone and antioxidant system imbalances. However, the biomass, plant height, stem diameter, total leaf area and leaf perimeter of M9-T337 seedlings were significantly increased after ZnO NP treatment. Specifically speaking, ZnO NPs can improve the photosynthetic capacity of M9-T337 by increasing the content of photosynthetic pigment, regulating photosynthetic intensity and chlorophyll fluorescence parameters. ZnO NPs can balance the osmotic adjustment system by increasing the contents of soluble protein (SP), soluble sugar (SS), proline (Pro) and starch, and can also enhance the activities of enzymatic (SOD, POD, and CAT) and non-enzymatic antioxidant enzymes (APX, AAO, GR, and MDHAR) to enhance the scavenging ability of reactive oxygen species (H2O2, O2•−), ultimately reducing oxidative damage; ZnO NPs promoted the growth of M9-T337 seedlings under saline alkali stress by synergistically responding to auxin (IAA), gibberellin (GA3), zeatin (ZT) and abscisic acid (ABA). Additionally, the Na+/K+ ratio was reduced by upregulating the expression of Na+ transporter genes (MdCAX5, MdCHX15, MdSOS1, and MdALT1) and downregulating the expression of K+ transporter genes (MdSKOR and MdNHX4). After comprehensive analysis of principal components and correlation, T3 (150 mg/L ZnO NPs) treatment possessed the best mitigation effect. In summary, 150 mg/L ZnO NPs(T3) can effectively maintain the hormone balance, osmotic balance and ion balance of plant cells by promoting the photosynthetic capacity of M9-T337 seedlings, and enhance the antioxidant defense mechanism, thereby improving the saline alkaline tolerance of M9-T337 seedlings.

Exploring and analyzing the causes of color in the earth

Color is an essential element of human visual perception, which exists in all aspects of our daily lives and plays a key role in scientific research and technological applications. Color is produced by various mechanisms, including absorption and reflection of chemical pigments, complex formation of transition metal ions, and micro- and nanostructural modulation of structural colors. This paper aims to comprehensively explore the scientific principles of color generation and its applications in different fields. The article first describes how transition metal ions exhibit colors by forming complexes and explains in detail the coordination process of copper ions in an aqueous solution and its resulting d-orbital splitting, which in turn absorbs light of specific wavelengths and exhibits complementary colors. Secondly, the article explores the mechanism of color expression of natural pigments in plants, significantly how pigment molecules containing conjugated double bonds, such as -carotene, can absorb specific wavelengths of light and exhibit vivid colors through electron delocalization and energy level jumps. Finally, the article illustrates the principles of structural color and its potential for industrial applications, including using micro- and nanostructures, such as photonic crystals, to modulate the scattering and absorption of light, thus enabling dynamic changes in color and environmental protection. The in-depth exploration of the mechanism of color generation enhances our understanding of the basic principles of color science. It provides theoretical support for technological innovation and practical applications in related fields.

Influence of Divalent and Trivalent Sources of Iron on Growth, Iron Uptake-Transport and Photosynthetic Pigments in Rice (Oryza sativa L.) Cultivars During the Vegetative Stage

ABSTRACT Rice (Oryza sativa L.) is the most significant staple food globally. It can cultivate in a wide range of environments. Iron (Fe) deficiency is an important abiotic stress in crop production. To deal with Fe deficiency, plants have evolved mechanisms for Fe uptake. The study aims to examine the abilities of the cultivars – Biga İncisi, Osmancık-97, Hamzadere, Ronaldo, and Edirne – to utilize both non-chelated (FeSO4·7 H2O) and chelated forms (Fe(II)-EDTA and Fe(III)-EDTA) of Fe, which exist in divalent and trivalent states, along with their physiological responses to these different forms of Fe. All cultivars were grown in a sand culture under Fe-deficient (Fe:0) and -sufficient conditions (45 µM Fe). Roots of all rice cultivars grown under Fe deficiency conditions exhibited both phytosiderophore (PS) release and ferric chelate reductase (FCR) activity. These results indicate that all cultivars can employ a Combined Strategy (Strategy I/II) mechanism for Fe uptake. Nevertheless, the efficiency of rice plants in utilizing Strategy I and Strategy II mechanisms for Fe uptake varied depending on the cultivars. Hamzadere exhibited higher PS production, whereas Ronaldo displayed higher FCR activity. The application of divalent and trivalent Fe sources significantly increased the dry weight of shoots, Fe uptake by shoots and roots, and the pigment content of leaves in the rice cultivars. For other cultivars except Hamzadere and Edirne, the utilization rate of Fe(II)-EDTA was higher than that of Fe(III)-EDTA and FeSO4.7 H2O. The cultivar Osmancık-97 had the highest utilization rate (21.30%) of Fe(II)-EDTA.

Photon budgets and the relative effects of CDOM and pigment absorptions on primary production along a coastal salinity gradient

The study highlights the critical role of CDOM in coastal light attenuation and its impact on primary production (PP). We investigated the spectral attenuation of light due to water, phytoplankton pigments, detritus and coloured dissolved organic matter (CDOM) along a salinity gradient in the outer Oslofjord, Norway. By examining the effects of these components across different seasons, we aimed to elucidate their relative contributions to light absorption and PP. The findings suggest that increased terrestrial CDOM inputs, driven by climate, changed atmospheric deposition and land-use changes, could significantly affect coastal ecosystems by altering light attenuation and consequently PP and potentially leading to other ecological pressures. CDOM consistently dominated light absorption across all stations and seasons, contributing 50%–80% of the total absorption of photosynthetically active radiation. The absorption by CDOM and detritus decreased with increasing salinity, while phytoplankton absorption followed a seasonal succession. PP estimates show high seasonal variability from maximums in June to minimums in November, mainly attributed to, changes in seasonal light availability and phytoplankton biomass, followed by light attenuation by CDOM and differences in quantum yields of photosystem II (PSII). Nutrient analysis showed a seasonal pattern, with the highest nitrogen concentrations in November and depletion during more productive seasons, as well as conservative mixing throughout the salinity gradient. CDOM absorption played substantial, albeit not leading, role in influencing PP estimates, derived from a bio-optical model. CDOM was the main determinant of light attenuation across most wavelegnths.

Improving natural red pigment production by Streptomyces phaeolivaceus strain GH27 for functionalization of textiles with in silico ADME prediction

The red pigment was recovered from the S. phaeolivaceus GH27 isolate, which was molecularly identified using 16S rRNA gene sequencing and submitted to GenBank as OQ145635.1. The ideal growth conditions included 1% (w/v) starch, diammonium citrate, dibasic sodium phosphate, 5% (v/v) inoculum, pH 8, a rotation speed of 150 rpm, a temperature of 37 °C, and an incubation period of 9 days. Using ethanol as a solvent, the red pigment was effectively recovered. Data indicates that pigment content remained steady at 40 and 50 °C. Heating the pigment extract to 60, 70, 80, 90, and 100 °C for one hour results in pigment retention of 98%, 96.5%, 95.5%, 94.6%, and 92.6% of its pigment density, respectively. Studies indicate that the pigment extracts exhibited optimal stability at alkaline pH levels. The findings demonstrate that the red pigment extract has a peak absorbance range of 280–340 nm, with a λmax of 300 nm. GC/MS analysis revealed that the primary components of the pigment extract were linolenic acid methyl ester and oleic acid methyl ester, constituting 26.41% and 25.25%, respectively. Fabrics dyed with extracted red pigment exhibit excellent fastness when using the comprehensive green method. In comparison to conventional and nanotechnological attributes, printed samples exhibit significant color strength without environmental repercussions. The treatment of cotton, wool, and polyester samples suppressed pathogen growth to differing extents. Polyester had the most important inhibitory effects on Staphylococcus aureus (50.03%) and Bacillus cereus (39.49%). The ADME physicochemical properties of the predominant medication were assessed, together with its bioavailability. The radar plot demonstrated ideal parameters for size, polarity, lipophilicity, solubility, and saturation, excluding flexibility. It exhibited intermediate synthetic accessibility, exceptional permeability and absorption, elevated gastrointestinal absorption, and blood–brain barrier penetration; nonetheless, it did not adhere to the medicinal chemistry rule of three.Graphical

Effects of Enterobacter cloacae extract, selenium nanoparticles and methyl jasmonate on shoot liquid cultures of Sarcocornia fruticosa under salinity stress

BackgroundThe in vitro propagation of halophytes is innovative perspective for sustainable agriculture, conservation of natural plants and essential raw materials for industry due to increasing soil salinization and decreasing freshwater availability. Sarcocornia fruticosa, a halophytic plant, may hold promise for biosaline production systems and achieve bioactive products. Understanding the salt tolerance mechanisms of halophytes through elicitors can enhance the production of secondary metabolites, such as phenolics and flavonoids, under saline environment. This study aimed to evaluate the effects of NaCl salinity (700 mM and 1000 mM) on Sarcocornia fruticosa shoot cultures and assess the influence of different elicitors-Enterobacter cloacae extract (BE), selenium nanoparticles (SeNPs) and methyl jasmonate (MeJA) -on the plants growth, physiological and biochemical responses, and isorhamnetin production.MethodologyShoot cultures were grown under controlled conditions with two concentrations of NaCl, alone and in combination with BE (0.5%), SeNPs (100 ppm), or MeJA (50 µM). Growth parameters, photosynthetic pigments, ion accumulation, osmolyte content, oxidative stress marker, enzyme activity, phenolic compound levels, and isorhamnetin production were analyzed to determine the impact of salinity and elicitor treatments on S. fruticosa for 14 days.ResultsSarcorcocnia fruticosa exhibited better tolerance up to 700 mM than 1000 mM NaCl, as evidenced by higher dry weights, chlorophyll a/b ratios, and enhanced osmolyte and antioxidant contents. Elicitation both saline cultures with BE and SeNPs improved growth mostly by increasing biomass, pigment contents, K+/Na+ ratios, and reducing lipid peroxidation, however, MeJA reduced the biomass mainly by increasing MDA and Na+ ion accumulation. In contrast, application of all elicitors stimulated the production of phenolic compounds and isorhamnetin, as well as BE can contribute for increasing resistance of S. fruticosa to stressful conditions.ConclusionThis study demonstrated that PTC techniques and appropriate elicitors can optimize halophyte propagation and secondary metabolite production under saline conditions. The findings suggest that BE and SeNPs significantly enhanced the growth and biochemical resilience of S. fruticosa under salinity stress, with a notable increase in isorhamnetin production. MEJA.

A Comparative Study on Drought Stress Response In Vitro and In Vivo Propagated Fragaria vesca Plants

The evaluation of plant responses to water deficit in the substrate, particularly in the context of intensifying climate change, represents a critical factor for ensuring stable agricultural production, economic resilience, and food security. The primary objective of this study was to compare the physiological and biochemical responses to water deficit in conventional cultivation of Fragaria vesca plants propagated both in vitro and in vivo. The research encompassed measurements of gas exchange parameters, chlorophyll “a” fluorescence, photosynthetic pigment and proline content in leaves, leaf relative water content index, total fruit yield, single fruit weight, fresh and dry mass of the root system, as well as the concentrations of K, Ca, Mg, Na, Cu, Zn, Mn, and Mo. Additionally, the ratio of monovalent to divalent cations in leaves, roots, and crowns was analyzed. The results revealed significant differences between the experimental variants under optimal conditions and their respective responses to drought stress. Plants derived from in vitro cultures, despite exhibiting initially lower physiological trait values, demonstrated higher yield potential (no significant difference in the yield of fresh fruit mass compared to a 78% reduction). However, a long-term lack of water caused greater damage to their photosynthetic system—a reduction in physiological traits to 80% was observed, compared to a maximum decrease of 40% in plants derived from seedlings. The results highlight that environmental conditions and the acclimatization process of plants derived from in vitro cultures can significantly influence their adaptive potential and productivity.

Cellular and biochemical alterations induced by diesel oil in the brown algaSargassum cymosumvar.stenophyllumcultured in vitro.

The effect of the in vitro acute exposure to diesel oil (0.001%, 0.01%, 0.1%, and 1%, v/v) has been evaluated in the brown seaweed Sargassum cymosum var. stenoplhyllum by determining the contents of photosynthetic pigments, phenolic compounds, and morphological and cellular changes. In vitro cultures of S. cymosum were exposed to diesel oil for 30min, 1h, 12h, and 24h under laboratory-controlled conditions. Chlorophyll a and c contents increased after diesel oil exposure as the amounts of carotenoids did not show a clear trend along the experimental period. However, a reduction in the concentration of phenolic compounds was detected by chemical analysis, a finding further corroborated by electron microscopy and cytochemical analyzes. The thickness of the cell wall showed to be augmented and the accumulation of phenolic compounds therein was also detected after exposure to that petroleum derivative. Besides, morphological analysis through scanning electron microscopy revealed irregularities in the cell surface, as transmission electronic microscopy indicated an increased number of vacuoles in the cells. Based on these results, it could be concluded that the acute exposure to diesel oil brings about a stress effect in S. cymosum var. stenophyllum, promoting alterations in the seaweed secondary metabolism, stimulating protective mechanisms against oxidative stress, and changing cell's morphological and ultrastructural traits.

Distinctive features of the dynamics of photosynthetic pigment contents and the number of cultivated endophytic bacteria forms in Ribes nigrum L. leaves

The article presents the results of studying the dynamics of photosynthetic pigment contents and the number of cultivated endophytic bacteria (EB) forms in leaves of cultivars of different genetic origin bred by FSBSO ARHCBAN. The research was conducted in 2021-2024 on the blackcurrant (Ribes nigrum L.) collection plantings of the Kokinsky experimental station (Bryansk Oblast) and the research department of the gene pool and bioresources (Stupinsky District, Moscow Oblast) of the FSBSO ARHCBAN. The cultivars included Barmaley, Bryansky Agat, Gamayun, Debryansk, Mif. Weather conditions during the growing season were found to have a signifi cant effect on the content of cultivated EB forms in leaves. On average, over the four-year research period, Bryansky Agat was determined to have the largest number of EB, i. e., up to 107,823 CFU/g. The cultivar was characterized by the most stable abundance indicators of cultivated EB forms in leaves. The blackcurrant cultivars Barmaley and Bryansky Agat were the most responsive to this indicator. The number of cultivated EB forms in their leaves predictably positively correlated with the number of sunny days, as well as with average values of daytime and nighttime temperatures in spring and fall. Except for Mif, all cultivars responded negatively or weakly to the amount of precipitation and daily mean temperature. The Debryansk cultivar was found to be the most unresponsive to weather factors, which may be associated with the lowest annual average number of cultivated EB forms in its leaves (70,713 CFU/g). The high content of cultivated EB forms and chlorophyll a in Bryansky Agat leaves may indicate a possible role of endophytic bacteria in stimulating the synthesis of photosynthetic pigments in blackcurrant leaves.

Zinc oxide nanoparticles foliar use and arbuscular mycorrhiza inoculation retrieved salinity tolerance in Dracocephalum moldavica L. by modulating growth responses and essential oil constituents

The production of medicinal plants under stressful environments offers an alternative to meet the requirements of sustainable agriculture. The action of mycorrhizal fungus; Funneliformis mosseae and zinc in stimulating growth and stress tolerance in medicinal plants is an intriguing area of research. The current study evaluated the combined use of nano-zinc and mycorrhizal fungus on the physiochemical responses of Dracocephalum moldavica under salinity stress. The study employed a factorial based on a completely randomized design with three replications. The treatments were different levels of salinity (0, 50, and 100 mM NaCl), two levels of mycorrhiza application (0 and 5 g kg− 1 of soil), and two levels of foliar spraying of nano zinc oxide (0 and 1000 ppm). Salinity decreased the photosynthetic pigments content, SPAD value, and chlorophyll fluorescence data (Fm, Fv, Fv/Fm). Plant dry weight, Na+ content, and essential oil content were significantly higher at 50 mM salinity + co-application of mycorrhiza and nano zinc oxide. Electrolyte leakage increased under salt stress, while mycorrhizal inoculation compensated for the trait. The main essential oil constituents were geranyl acetate, nerol, geranial, geraniol, viridiflorol, hexadecane, humulene, and germacrene D. Energy metabolism demonstrates the effectiveness of treatment combinations in promoting the biosynthesis and accumulation of essential oil components. The overall results with more comprehensive field-based studies would be advisable for the extension section to utilize marginal salty lands for the reliable production of a valuable medicinal plant.

Quantitative trait loci mapping and genomic selection for leaf-related traits in a ‘Luli’ × ‘Red No. 1’ apple hybrid population

Apple (Malus spp.) is a widely cultivated economic crop. Leaf-related traits, such as leaf size, pigment content, and photosynthetic rate, serve as important indicators of light use efficiency and are associated with apple fruit quality and potential yields. Identifying quantitative trait loci (QTLs) and genes related to these traits is essential for plant breeding. Genomic selection (GS) presents a promising approach, particularly for improving leaf-related traits in apples. This study focused on identifying QTLs and associated genes, and evaluating the use of GS for leaf-related traits in apples. By genotyping an F1 population (‘Luli’ × ‘Red No. 1’) and constructing a high-density linkage map with 3,759 bin markers, 69 QTLs related to leaf traits were identified, explaining 10.4∼17.8% of the phenotypic variance. Forty-six candidate genes were predicted from these QTLs, resulting in 14, 14, 13, and 5 genes for leaf size, pigment content, photosynthetic rate, and fast chlorophyll fluorescence parameters, respectively. The study also assessed the accuracy of GS prediction for leaf traits using genome-wide markers and QTL interval markers through a 10-fold cross-validation. Results indicated that ridge regression BLUP (RR-BLUP) and gradient boosting decision tree (GBDT) methods using QTL interval SNP markers demonstrated higher prediction accuracies compared to whole genome markers for most traits, suggesting the feasibility of employing QTL interval markers for GS prediction. Notably, all models provided valuable genome prediction results with 4K markers or when the training population represented 80% of the total population. These findings significantly contribute to gene discovery and genetic improvement efforts related to leaf traits while highlighting the potential utility of GS in accelerating apple breeding programs.

Effect of Bio and Nitrogen Fertilizers on Growth Aspect and Leaf Content of Mineral and Pigment of Washington Navel Orange Trees

Effect of Bio and Nitrogen Fertilizers on Growth Aspect and Leaf Content of Mineral and Pigment of Washington Navel Orange Trees

Role of polyethylene glycol to alleviate lead stress in Raphanus sativus.

The continuous contamination of heavy metals (HMs) in our ecosystem due to industrialization, urbanization and other anthropogenic activities has become a serious environmental constraint to successful crop production. Lead (Pb) toxicity causes ionic, oxidative and osmotic injuries which induce various morphological, physiological, metabolic and molecular abnormalities in plants. Polyethylene glycol (PEG) is widely used to elucidate drought stress induction and alleviation mechanisms in treated plants. Some recent studies have unveiled the potential of PEG in regulating plant growth and developmental procedures including seed germination, root and shoot growth and alleviating the detrimental impacts of abiotic stresses in plants. Therefore, the current study aimed to assess the effects of seed priming with various concentrations (10%, 20%, 30% and 40%) of PEG on the growth and development of radish plants growing under Pb stress (75 mg/kg soil). Lead toxicity reduced root growth (32.89%), shoot growth (32.81%), total chlorophyll (56.25%) and protein content (58.66%) in treated plants. Similarly, plants showed reduced biomass production of root (35.48%) and shoot (31.25%) under Pb stress, while 30% PEG seed priming enhanced biomass production of root (28.57%) and shoot (35.29%) under Pb contaminated regimes. On the other hand, seedlings obtained from 30% PEG priming demonstrated a notable augmentation in the concentrations of photosynthetic pigments, antioxidative activity and biomass accumulation of the plants. PEG-treated plants showed modulations in the enzymatic activities of peroxidase (PO), catalase (CAT) and superoxide dismutase (SOD). These changes collectively played a role in mitigating the adverse effects of Pb on plant physiology. Our data revealed that PEG interceded stress extenuation encompasses numerous regulatory mechanisms including scavenging of ROS through antioxidant and non-antioxidants, improved photosynthetic activity and appropriate nutrition. Hence, it becomes necessary to elucidate the beneficial role of PEG in developing approaches for improving plant growth and stress tolerance.

Harnessing Nature's Palette: Exploring Photosynthetic Pigments for Sustainable Biotechnology.

Photosynthetic microorganisms such as cyanobacteria, microalgae, and anoxygenic phototrophic bacteria (APB) have emerged as sustainable and economic biotechnology platforms due to their ability to transform energy from light into chemicals through photosynthesis. The light is absorbed by photosynthetic pigment-protein antenna complexes which are composed of pigments such as bacteriochlorophylls (BChl) and carotenoids in APB, and chlorophylls (Chl), phycobiliproteins (PBP), and carotenoids in cyanobacteria and microalgae. These photosynthetic pigments are essential in the physiology of photosynthetic microorganisms and offer significant health benefits due to their potent antioxidant activity, with properties that include anticancer, antiaging, antiproliferative, anti-inflammatory, and neuroprotective effects. This review first provides an overview of current advances in photosynthetic pigment synthesis and the latest strategies to increase pigment content in cyanobacteria, microalgae, and APB. It then delves into the pigment production process, covering biosynthetic pathways, critical environmental parameters, and extraction methods. Finally, the potential marketability of photosynthetic pigments together with current limitations are discussed.

Preliminary Study on the Potential of Red Fruit Pigment (Pandanus conoideus) from West Papua as Dye-Sensitized Solar Cell (DSSC)

The red fruit (Pandanus conoideus) is an endemic plant from Papua, known for its distinctive color and shape. This fruit is recognized for its bioactive properties, such as antioxidant, anti-inflammatory, and antihyperglycemic effects. Its high pigment content is believed to have potential as a sensitizer in DSSC applications. However, research on this topic remains underexplored. Therefore, the aim of this preliminary study is to investigate the potential of red fruit pigments for DSSC. The characterization of red fruit pigments was conducted through phytochemical screening, FTIR and UV-Vis spectral analysis, as well as literature reviews. Pigment extraction was carried out using maceration without involving drying or grinding processes. Phytochemical screening results revealed that the macerate contains flavonoids, alkaloids, phenolics and terpenoids, compounds commonly used as natural pigments in DSSCs. FTIR analysis showed the presence of functional groups such as carboxyl (-COOH), carbonyl (C=O), and hydroxyl (-OH), which can act as effective anchoring groups when interacting with nanosemiconductor surfaces. Meanwhile, UV-Vis analysis showed absorption peaks in the UV region (wavelength 204–399 nm) and the visible region (wavelength 400–550 nm). Based on literature studies and research findings, it can be concluded that the pigments in red fruit have potential applications as DSSC sensitizers.

Effects of triiodobenzoic acid on growth, yield and photosynthetic pigmentcontent of chickpea (cicer arietinum l.)

An experiment was conducted to evaluate the effect of seed soaking treatment of TIBA (10, 15, 20, 25, 30 and 35 ppm) on growth, yield and photosynthetic pigment content of chickpea var. BARI Chhola-6. Results revealed that TIBA had mostly retarding effects on plant height of BARI Chhola-6 with both significant and non-significant variations. The Number of branches and leaves per plant was positively influenced following all concentrations of TIBA where, seed treated with 35 ppm TIBA produced the highest values. Results revealed that TIBA treatments had inducing effects on flower initiation and completion. Application of TIBA induced the yield and yield attributes of BARI Chhola-6 where, 30 ppm TIBA produced the highest number of pods (72.25), maximum number of seeds per plant (112.13), 100-seed weight (23.84g) and yield per plant (15.92g). TIBA had pronounced effects on the photosynthetic pigment content of BARI Chhola-6 although 35 ppm TIBA resulted maximum values but not significantly different from 30 ppm and some other treatments. Of seven treatmnts, 30 ppm TIBA produced better stimulations. Bangladesh J. Bot. 53(4): 949-955, 2024 (December)

Transcriptome sequencing and anthocyanin metabolite analysis involved in leaf red color formation of Cinnamomum camphora

Cinnamomum camphora, a key multifunctional tree species, primarily serves in landscaping. Leaf color is crucial for its ornamental appeal, undergoing a transformation to red that enhances the ornamental value of C. camphora. However, the molecular mechanisms underlying this transformation remain largely unexplored. In this study, green leaf (GL), color turning red leaf (RL) and whole red leaf (WRL) were obtained to measure pigment contents, while GL and RL were analyzed for transcriptomic alterations. A decline in chlorophyll content and a rise in anthocyanins were observed during the transition from green to red leaves. Using LC MS/MS, 11 types of anthocyanins showed significant accumulative differences, with cyanidin-3,5-O-diglucoside exhibiting the greatest disparity. Comparative RNA-seq identified 22,948 genes against reference genes, revealing 544 novel genes. Of these, 3,222 genes were up-regulated and 7,391 genes were down-regulated when the FPKM mean value > 1 in at least one group. The ribosome was identified as the most abundant KEGG term, with a substantial number of down-regulated differentially expressed genes (DEGs). The results indicated a downward trend in protein content, with GL exhibiting the highest protein concentration. 22, 4, and 29 DEGs were associated with chlorophyll biosynthesis, chlorophyll degradation, and anthocyanin biosynthesis, respectively. Most DEGs related to chlorophyll biosynthesis were down-regulated. SGR and SGRL, which are associated with chlorophyll degradation, exhibited opposite differential expression, resulting in a significant decrease in chlorophyll content in RL. The significantly up-regulated genes ANS and UFGT are advantageous for anthocyanin biosynthesis, contributing to the red coloration observed. Additionally, differential expression was noted in 40 R2R3-MYBs. Two MYB90 (Ccam01G003512 and Ccam01G003515) homologs of AtMYB113 were also identified showed high levels of up-regulation in RL. These findings suggest a strong correlation between pigment metabolism and transcriptome data, elucidating the mechanism that leads to the red coloration of leaves in C. camphora.

Photosynthetic response of Solidago gigantea Aition and Calamagrostis epigejos L. (Roth) to complex environmental stress on heavy metal contaminated sites

Studies of in situ plant response and adaptation to complex environmental stresses, are crucial for understanding the mechanisms of formation and functioning of ecosystems of anthropogenically transformed habitats. We study short- and long-term responses of photosynthetic apparatus (PSA) and anti-oxidant capacity to complex abiotic stresses of common plants Calamagrostis epigejos and Solidago gigantea in semi-natural (C) and heavy metal contaminated habitats (LZ). We found significant differences in leaf pigment content between both plant species growing on LZ plots and their respective C populations. The average values of leaf chlorophyll indexes were 27% lower in the LZ populations of both species and significantly lower in Sg plants in comparison to Ce ones. The average values of the anthocyanin index in CeLZ and SgLZ populations were significantly higher (by 18%) than in their respective controls. In both Ce and Sg plants occurring on LZ plots, the average leaf flavonol indexes were higher than on their controls by 31% and 15% and this index was significantly higher in SgLZ population than CeLZ and CeC plants (by 34% and 54%, respectively). Both Ce and Sg populations growing on LZ plots showed significantly lower photosynthetic rate (A), transpiration rate (E) and stomatal conductance (gs) in comparison to controls. On the other hand, a significantly higher photosynthetic rate was detected in SgLZ than in CeLZ populations. The catalase activities were significantly higher than recorded in Sg than in Ce tissues, irrespective of the plot type. They were also higher in LZ populations than those in controls for both species. Moreover, the H2O2 content in Sg tissues was significantly higher than those in Ce. Hydrogen peroxide content in CeLZ and SgLZ were respectively 39% (non-significant) and 57% higher, compared to their controls. The reverse pattern was found in the case of MDA, whose concentration was significantly higher in the leaves of Ce population compared to the control population. The average MDA concentration in CeLZ populations was 17% higher than in the CeC. In the case of Sg no significant differences were found. Mechanisms of plant species adaptation to industrial areas are crucial for species selection and planning effective reclamation of them. The analysis of chlorophyll fluorescence induction curves as well as well as the results of JIP test revealed the decreased of Fj value despite positive ΔK–band in SgLZ and CeLZ plants suggesting the increased rate of electron transfer from QA to QB at the acceptor side of PSII, thus a high quantity of P680+ and/or effective quenching by exogenous molecules. The increase in the I–P part of the induction curve typically attributed to the reduction of electron transporters (ferredoxin, intermediary acceptors, and NADP) of the PSI acceptor side was observed in both SgC and SgLZ but not in CeLZ populations. These changes demonstrate species-specific effects on electron transport during the light phase of photosynthesis under complex environmental stress. Our results show that Sg and Ce individuals developed a range of structural and functional adaptations to protect PSA against complex environmental stresses (possible combination of heavy metals, water deficiency, temperature, nutrient deficiency and salinity). Both species from LZ plots could tolerate high levels of Cd, Zn and Pb in leaf tissues. Therefore they can be potential candidates for use in phytoremediation of HM contaminated areas. However, further long-term field and experimental research on plant traits response and adaptation to complex environmental stresses on industrial habitats are needed.

Cytological, Physiological, and Transcriptome Analysis of Leaf-Yellowing Mutant in Camellia chekiangoleosa.

Color variation in plant leaves has a significant impact on their photosynthesis and plant growth. Camellia chekiangoleosa yellow-leaf mutants are ideal materials for studying the mechanisms of pigment synthesis and photosynthesis, but their mechanism of leaf variation is not clear. We systematically elucidated the intrinsic causes of leaf yellowing in the new Camellia chekiangoleosa variety 'Diecui Liuji' in terms of changes in its cell structure, pigment content, and transcript levels. This study indicates that the incomplete structure of chloroplast-like vesicles, the decrease in blue-green chlorophyll a, and the increase in yellow-green chlorophyll b in yellowing leaves are the direct causes of yellowing-leaf formation. The high expression of genes that catalyze the degradation of chlorophyll a (PAO and RCCR) and its conversion to chlorophyll b (CAO) in yellowing leaves leads to a decrease in the chlorophyll a content, while the low expression of CLH genes is the main reason for the increase in the chlorophyll b content. We also found transcription factors such as ERF, E2F, WRKY, MYB, TPC, TGA, and NFYC may regulate their expression. RT-qPCR assays of 12 DEGs confirm the RNA-seq results. This study will provide a foundation for investigating the transcriptional and regulatory mechanisms of leaf color changes.