Ratio Of Chlorophyll Research Articles

Influence of various organomineral biological preparations on the productivity and composition of the chlorophyll complex of spring wheat

Abstract In a field experiment, the influence of various organomineral biological products on the yield and composition of the chlorophyll complex of spring wheat was studied. As a result of research, it was found that organomineral complexes have a positive effect on increasing productivity. Special implementation options using OMC+Zn and OMC+Si. In addition, organomineral biological products have a significant impact on the composition and structure of the chlorophyll complex. To analyze the chlorophyll complex, two indicators were studied: the total content of chlorophylls a and b, and the ratio of chlorophylls a and b. The most optimal and effective in these two indicators was the option using OMC+Zn.

Закономерности содержания пигментов в листьях морозоустойчивых технических сортов винограда в зависимости от сортовых особенностей и фаз вегетации

Abstract. The study of the pigment complex of the main and lateral leaves of three dark-berry frost-resistant grape varieties of domestic breeding Vecherniy, Dmitriy and Kurchanskiy was carried out., The content of chlorophylls (a, b) and carotenoids in the phases of berry growth and ripening was determined using the spectrometric method. Based on the obtained data, the sum of chlorophylls, as well as the ratio of chlorophyll a to chlorophyll b and the sum of chlorophylls to carotenoids were calculated. It was revealed that the pigment content in the leaves depended on varietal characteristics, vegetation phase and leaf type (main, lateral leaves). A general trend towards a decrease in chlorophyll a was observed in the ripening phase of grapes, the control variety Dmitriy had an increase in chlorophyll b, the sum of chlorophylls and a decrease in carotenoids, while the varieties Vecherniy and Kurchanskiy had a decrease in chlorophyll b, the sum of chlorophylls and an increase in carotenoids. During the berry growth phase, the most optimal ratio of chlorophyll a to chlorophyll b was observed in the leaves of the control variety Dmitriy, and during the berry ripening phase – in the leaves of the varieties Vecherniy and Kurchanskiy, which indicates that the plants of these varieties were in a normal physiological state during these periods. In the Vecherniy and Kurchanskiy varieties during the berry growth phase and in the Dmitry variety during the ripening phase, the ratio between the pigment content significantly decreased, which is a sign of a stressful state of the plants. During the berry growth phase, the chlorophylls of the leaves of the control variety Dmitriy were better protected from photooxidation than those of the other two varieties, since the ratio of the sum of chlorophylls to carotenoids was 2.05-3.22 times less than that of the Vecherniy and Kurchanskiy varieties. During the berry ripening phase, for the same reason, the chlorophylls of the Vecherniy and Kurchanskiy varieties were better protected from destruction. The obtained data confirm the fact established by other researchers that the pigment complex of leaves can serve as an indicator of the degree of resistance of the grape plant to stress factors during the growing season. Keywords: grapes, variety, vegetation phases, leaf chlorophylls, leaf carotenoids, stress resistance

Construction of Freezing Injury Grade Index for Nanfeng Tangerine Plants Based on Physiological and Biochemical Parameters.

Low-temperature freezing stress constitutes the most significant meteorological disaster during the overwintering period in the Nanfeng Tangerine (NT) production area, severely impacting the normal growth and development of the plants. Currently, the accuracy of meteorological disaster warnings and forecasts for NT orchards remains suboptimal, primarily due to the absence of quantitative meteorological indicators for low-temperature freezing stress. Therefore, this study employed NT plants as experimental subjects and conducted controlled treatment experiments under varying intensities of low-temperature freezing stress (0 °C, -2 °C, -5 °C, -7 °C, and -9 °C) and durations (1 h, 4 h, and 7 h). Subsequently, physiological and biochemical parameters were measured, including photosynthetic parameters, chlorophyll fluorescence parameters, reactive oxygen species, osmoregulatory substances, and antioxidant enzyme activities in NT plants. The results demonstrated that low-temperature freezing stress adversely affected the photosynthetic system of NT plants, disrupted the dynamic equilibrium of the antioxidant system, and compromised cellular stability. The severity of freezing damage increased with decreasing temperature and prolonged exposure. Chlorophyll (a/b) ratio (Chl (a/b)), maximum quantum yield of photosystem II (Fv/Fm), soluble sugar, and malondialdehyde (MDA) were identified as key indicators for assessing physiological and biochemical changes in NT plants. Utilizing these four parameters, a comprehensive score (CS) model of freezing damage was developed to quantitatively evaluate the growth status of NT plants across varying low-temperature freezing damage gradients and durations. Subsequently, the freezing damage grade index for NT plants during the overwintering period was established. Specifically, Level 1 for CS ≤ -0.50, Level 2 for -0.5 < CS ≤ 0, Level 3 for 0 < CS ≤ 0.5, and Level 4 for 0.5 < CS. The research results provide valuable data for agricultural meteorological departments to carry out disaster monitoring, early warning, and prevention and control.

Constructing 3D SPAD distribution using hyperspectral LiDAR point cloud by PROSPECT model inversion

ABSTRACT Accurately estimating leaf chlorophyll concentrations in a three-dimensional (3D) manner is crucial for precisely monitoring crop growth and development. To reduce destructive detection and achieve real-time estimation, researchers often utilize crop leaves’ SPAD (Soil and Plant Analyzer Development) to represent relative chlorophyll content. However, SPAD measurement is time-consuming and laborious work. Many inversion methods have been proposed to estimate SPAD based on one-dimensional reflectance or two-dimensional spectral images, which rely on external light sources and also cannot obtain 3D distribution. Hyperspectral LiDAR (HSL), as an active remote sensing technology, can acquire target spatial and spectral data simultaneously, making 3D SPAD inversion and reconstruction possible. This research aims to invert SPAD values with HSL spectral information aided by the PROSPECT model and reconstruct 3D SPAD distribution with HSL spatial information. Firstly, we constructed new ratio chlorophyll indices (RCI) based on the multi-feature analysis method with the PROSPECT model and HSL spectral data. Next, we employed RCIs to modify the Look-Up Table (LUT) cost function (SPAD-LUT) of the PROSPECT model, which was validated with the ANGERS dataset. Then, we conducted SPAD inversion with HSL spectral information from vegetable crop samples and integrated the inverted SPAD values into their corresponding 3D coordinates, achieving 3D SPAD distribution reconstruction. The predicted values of the model inversion with the HSL dataset are consistent with the measured SPAD (R2 = 0.421, RMSE = 10.615). The results indicate that our method can invert sample SPAD values and reconstruct their distribution with HSL point cloud despite their complex spatial structure.

Combined applications and Multi-Faceted evaluations of humic acid, seaweed, and vermicompost with chemical and organo-mineral fertilizers on corn, part I: chlorophyll concentration

This study investigated the effects of various fertilizers on the leaf chlorophyll content of the Simpatico (FAO300) silage corn variety under field conditions. Different application combinations were tested, including treatments with and without foliar fertilizers. The foliar fertilizers used were seaweed (SW), humic acid (HA), and vermicompost (VC), combined with granular fertilizers DAP, UREA, OMB, and OMT. Granular fertilizers were applied to the soil, while foliar fertilizers were applied at four different stages: the 4-6 leaf period, 11-13 leaf period, 14-16 leaf period, and at corn tassel. Chlorophyll content in plant leaves was measured using a SPAD-502 device during these periods. The highest SPAD chlorophyll ratios were recorded with OMB-OMT (42.583) and DAP-OMT (42.150) treatments, which did not include foliar fertilizers. Conversely, the lowest SPAD chlorophyll ratio, 28.983, was observed in the DAP-UREA treatment. Treatments with foliar fertilizers resulted in an increase in SPAD chlorophyll by 11.3% to 15.7%, with the greatest improvements observed with vermicompost and humic acid, compared to treatments without foliar fertilizers. Additionally, analysis of periodic effects showed that the highest SPAD chlorophyll ratios were found during the third and second measurement periods, while the lowest ratios were observed in the first measurement period. The use of organo-mineral fertilizers and foliar applications of vermicompost and humic acid were found to enhance the leaf chlorophyll content of corn.

Фотосинтетическая активность подроста хвойных в связи с промышленными рубками

The functioning of coniferous undergrowth of preliminary and subsequent generations after industrial felling was considered in the middle taiga subzone of the Komi Republic. Using spectrophotometric and gasometric methods we analyzed the pigment activity, photosynthetic, and respiratory abilities of the assimilation apparatus of pine (Pinus sylvestris L.) and spruce (Picea obovata Ledeb.) undergrowth at the 3- and 10-year old clearings. The pigment apparatus functional rearrangement of the preliminary generation spruce undergrowth at clearings was found. Needles adapt to environmental conditions at the pigment system level by changing the content and ratio of chlorophylls and carotenoids. Changes in plastids in the spruce undergrowth at the 3-year clearings occurred due to a decrease in chlorophyll and carotenoid concentrations, and at the 10-year clearings due to activation of pigment synthesis which affects the carbon dioxide absorption in chloroplasts. The assimilation apparatus of spruce undergrowth at clearing absorbs CO2 by 1.4 and 1.8 time more actively than that under the forest canopy. The photosynthetic and respiratory abilities of spruce needles at clearings do not differ. This indicates a stable level of important vital processes for the studied undergrowth at clearings during ten years after felling. Pine and spruce undergrowth needles are able to absorb CO2 at a fairly high rate up to 5.73 and 2.7 μmol CO2/(m2 · s) respectively. This rate contributes to the accumulation of assimilates in pine needles and their use for growth which logically increases the productivity of undergrowth at clearings. In general, the functional organization of spruce and pine undergrowth assimilating organs ensures their growth and favors the successful restoration of conifers at clearings in the middle taiga subzone of the European North-East.

The regulation of photosynthesis and growth of rapeseed seedling by the interaction of red and yellow lights with blue light

The interactive regulation among different lights on plant life-activities has not yet been fully understood. In the study, we investigated the interaction of red light (R) and yellow light (Y) with blue light (B) on growth and photosynthesis of rapeseed seedlings. The results showed Y and R as well as their combination of RY were not beneficial for plant photosynthesis and growth, but a quarter addition of B (RB, YB and RBY) obviously reversed these negative effects, improving stomatal behavior, leaf and root developments, photosynthetic traits, as well as synthesis and transport of photosynthetic products. Available light energy and B intervention together decreased the ratio of chlorophyll b (Chl b) to carotenoid (Car), while the opposite effect was observed in the absence of B treatments. Among the various lights, RY and Y significantly upregulated the majority of genes associated with chlorophyll metabolism, while RB predominantly upregulated genes related to the two photosystems (PS). Conversely, B and YB treatments generally suppressed the expression of these genes. Despite these differences in gene expression, the ratios of PSI/PSII to Chl b/Car were consistently maintained around 0.56 in the RB, YB, and RBY treatments. In contrast, this ratio was higher at 0.64 in the B treatment and lower, at less than 0.44, in the R, Y, and RY treatments. These ratios reflect the balance between light supply and utilization in plants under different lights, where plants under RB, YB, and RBY might achieve optimal light environments, while plants under B and under R, Y, and RY experienced high and low light stress, respectively. In conclusion, all combinations of B with R, Y or RY can be used for rapeseed cultivation, and the ratio of Chl b/Car to PSI/PSII might be an important reference index to select optimal light combinations for crop production.

Вміст пластидних пігментів у дерев сосни звичайної уражених сосновим вертуном в умовах Західного Полісся

The biosynthesis of plastid pigments in Pinus sylvestrys L.was investigated in pine trees affected by Melampsora pinitorqua in the conditions of the Western Polissya. The total content of chlorophylls and carotenoids in the needles of trees with a mild and moderate degree of damage by Melampsora pinitorqua is 13,3…30,0% lower than in the control. Trees severely affected by Melampsora pinitorqua synthesize 21.8...38.4% less green and yellow pigments. A decrease in the content of green pigments in experimental pine trees is caused by chlorophyll a. Іt influences on absorption direct sunlight for the process of photosynthesis. The ratio of chlorophylls a/b is close to the control in experimental trees with a mild and moderate degree of disease damage and decreases by 23.3...32.9% in trees with a severe degree of disease damage. Іn all affected trees, the ratio between the amount of green and yellow pigments is close to the control.

Net O2 exchange rates under dark and light conditions across different stem compartments.

Woody plants display some photosynthetic activity in stems, but the biological role of stem photosynthesis and the specific contributions of bark and wood to carbon uptake and oxygen evolution remain poorly understood. We aimed to elucidate the functional characteristics of chloroplasts in stems of different ages in Fraxinus ornus. Our investigation employed diverse experimental approaches, including microsensor technology to assess oxygen production rates in whole stem, bark, and wood separately. Additionally, we utilized fluorescence lifetime imaging microscopy (FLIM) to characterize the relative abundance of photosystems I and II (PSI : PSII chlorophyll ratio) in bark and wood. Our findings revealed light-induced increases in O2 production in whole stem, bark, and wood. We present the radial profile of O2 production in F. ornus stems, demonstrating the capability of stem chloroplasts to perform light-dependent electron transport. Younger stems exhibited higher light-induced O2 production and dark respiration rates than older ones. While bark emerged as the primary contributor to net O2 production under light conditions, our data underscored that wood chloroplasts are also photosynthetically active. The FLIM analysis unveiled a lower PSI abundance in wood than in bark, suggesting stem chloroplasts are not only active but also acclimate to the spectral composition of light reaching inner compartments.

Genotype-specific nonphotochemical quenching responses to nitrogen deficit are linked to chlorophyll a to b ratios

Non-photochemical quenching (NPQ) protects plants from photodamage caused by excess light energy. Substantial variation in NPQ has been reported among different genotypes of the same species. However, comparatively little is known about how environmental perturbations, including nutrient deficits, impact natural variation in NPQ kinetics. Here, we analyzed a natural variation in NPQ kinetics of a diversity panel of 225 maize (Zea mays L.) genotypes under nitrogen replete and nitrogen deficient field conditions. Individual maize genotypes from a diversity panel exhibited a range of changes in NPQ in response to low nitrogen. Replicated genotypes exhibited consistent responses across two field experiments conducted in different years. At the seedling and pre-flowering stages, a similar portion of the genotypes (∼33%) showed decrease, no-change or increase in NPQ under low nitrogen relative to control. Genotypes with increased NPQ under low nitrogen also showed greater reductions in dry biomass and photosynthesis than genotypes with stable NPQ when exposed to low nitrogen conditions. Maize genotypes where an increase in NPQ was observed under low nitrogen also exhibited a reduction in the ratio of chlorophyll a to chlorophyll b. Our results underline that since thermal dissipation of excess excitation energy measured via NPQ helps to balance the energy absorbed with energy utilized, the NPQ changes are the reflection of broader molecular and biochemical changes which occur under the stresses such as low soil fertility. Here, we have demonstrated that variation in NPQ kinetics resulted from genetic and environmental factors, are not independent of each other. Natural genetic variation controlling plastic responses of NPQ kinetics to environmental perturbation increases the likelihood it will be possible to optimize NPQ kinetics in crop plants for different environments.

МЕТОДОЛОГИЯ УПРАВЛЕНИЯ АГРОБИОЛОГИЧЕСКОЙ, АДАПТИВНОЙ И ПРОДУКЦИОННОЙ УСТОЙЧИВОСТЬЮ НАСАЖДЕНИЙ ВИНОГРАДА В НЕСТАБИЛЬНЫХ ПОГОДНЫХ УСЛОВИЯХ И ТЕХНОГЕННОЙ ИНТЕНСИФИКАЦИИ ПРОИЗВОДСТВА

The article presents the results of agrobiological and physiological-biochemical studies to ensure the stability of grape plantations in unstable weather conditions and anthropogenic intensification of production. Studies in the agroecological conditions of the Krasnodar region on the southern chernozems revealed the most productive norm of loading of grape bushes with shoots for the technical varieties Kurchanskiy, Dmitriy, Vladimir, Granatovyi, Antaris and Alkor, on leached chernozems – for the table seedless variety Centennial Seedless. According to the results of electrophoretic separation of peroxidases in polyacrylamide gel and an increased content of ascorbic acid, increased frost resistance was established in the varieties Kristall, Vostorg, Krasnostop AZOS. The Vostorg and Zarif varieties proved to be more adaptive to the stresses of the summer period in terms of leaf hydration, bound water content, the ratio of chlorophylls and carotenoids, the amount of proline and water-soluble sugars, membrane permeability. The role of physiologically active substances in increasing the adaptive potential of grape plants has been established. The treatment of Merlot vines with methyl jasmonate and epibrassinolide during deep dormancy period, as well as proline, salicylic acid and epibrassinolide during induced dormancy period had a positive effect on the condition of the vine: there was a decrease in electrolyte yield. Sustainable grape cultivation is achieved with the systemic use of the «Bioconcentrate-Z» effluent by the non-root method. Against the background of nonroot treatments of Merlot and Cabernet Sauvignon varieties, a higher level of plant water supply, an increase in potassium content, green pigments, organic acids and grape yields were established. Physiologically active compounds and the preparation Turinbash have a positive effect in intensive own-root plantations of native and promising introduced grape varieties against the background of phylloxera infection in the southern part of Dagestan. The created yield forecasting method based on the NDVI of the grape plant and the actual data of multispectral images of the phenophases of flowering and growth allows to increase the accuracy of the calculated yield capacity to the actual one with a deviation from 0 to 0.8 kg per bush, the accuracy of the forecast increases by 2 times by the end of the growth phase and by the beginning of the maturation phase. Key words: GRAPES, METHODS, MANAGEMENT, SUSTAINABILITY, PRODUCTIVITY, QUALITY, FORECASTING

Chlorophyll Fluorescence Imaging for Environmental Stress Diagnosis in Crops.

The field of plant phenotype is used to analyze the shape and physiological characteristics of crops in multiple dimensions. Imaging, using non-destructive optical characteristics of plants, analyzes growth characteristics through spectral data. Among these, fluorescence imaging technology is a method of evaluating the physiological characteristics of crops by inducing plant excitation using a specific light source. Through this, we investigate how fluorescence imaging responds sensitively to environmental stress in garlic and can provide important information on future stress management. In this study, near UV LED (405 nm) was used to induce the fluorescence phenomenon of garlic, and fluorescence images were obtained to classify and evaluate crops exposed to abiotic environmental stress. Physiological characteristics related to environmental stress were developed from fluorescence sample images using the Chlorophyll ratio method, and classification performance was evaluated by developing a classification model based on partial least squares discrimination analysis from the image spectrum for stress identification. The environmental stress classification performance identified from the Chlorophyll ratio was 14.9% in F673/F717, 25.6% in F685/F730, and 0.209% in F690/F735. The spectrum-developed PLS-DA showed classification accuracy of 39.6%, 56.2% and 70.7% in Smoothing, MSV, and SNV, respectively. Spectrum pretreatment-based PLS-DA showed higher discrimination performance than the existing image-based Chlorophyll ratio.

Correlative relationship of amounts of chlorophyll "a" and "b" pigments in plants with anthocyanin ridges L-2, L-3, F1, Fb, F2

In the article: Based on the results of the experiments, the following scientific opinion is expressed. Experiments have shown that the separate actions of salinization and alkalization did not significantly affect the value of the ratio of chlorophyll a to chlorophyll b. The absence of significant changes in the value of this indicator indicates that these factors do not affect the light collection complex of the thylakoid membranes of this test crop

Atmospheric deposition and river runoff stimulate the utilization of dissolved organic phosphorus in coastal seas

In coastal seas, the role of atmospheric deposition and river runoff in dissolved organic phosphorus (DOP) utilization is not well understood. Here, we address this knowledge gap by combining microcosm experiments with a global approach considering the relationship between the activity of alkaline phosphatases and changes in phytoplankton biomass in relation to the concentration of dissolved inorganic phosphorus (DIP). Our results suggest that the addition of aerosols and riverine water stimulate the biological utilization of DOP in coastal seas primarily by depleting DIP due to increasing nitrogen concentrations, which enhances phytoplankton growth. This “Anthropogenic Nitrogen Pump” was therefore identified to make DOP an important source of phosphorus for phytoplankton in coastal seas but only when the ratio of chlorophyll a to DIP [Log10 (Chl a / DIP)] is larger than 1.20. Our study therefore suggests that anthropogenic nitrogen input might contribute to the phosphorus cycle in coastal seas.

Features of accumulation of sulfur and phosphorus by phytoremediants from technogenically polluted wastewater of mining enterprises

The article presents data on the accumulation of phosphorus and sulfur in the tissues of phytoremediant plants Phragmites australis (Cav.) Trin. ex Steud., Typha angustifolia L., Typha latifolia L., used for the treatment of technogenically polluted wastewater from mining enterprises. The dynamics of changes in digital biomass and normalized chlorophyll ratio index during systematic exposure to mine wastewater is shown. Species have been identified that respond to anthropogenic influence by increasing leaf mass and activating the photosynthetic system of plants. The high degree of phytoextraction of phosphorus and sulfur by Phragmites australis allows us to recommend this species for the production of green fertilizers based on it.

MINERAL STATUS OF GREEN PEAS GROWTH BY DROUGHT AND AMINO ACID SPRAYING

A greenhouse pot experiment was conducted 2023 at the National Research Centre in Dokki, Cairo, Egypt to investigate the impact of proline and glutamic acid on the growth, photosynthetic pigments, and mineral levels of Green Peas plants. The absence of irrigation has a detrimental impact on the growth of Green Peas plants, namely in terms of plant height, number of green leaves and stem, as well as the dry weight of leaves and top. The depressing impact was greater when irrigation was absent during the blossoming stage compared to the filling stage. This statement holds true for the conditions indicated earlier. In general, the utilization of amino acids (namely glutamic and proline) enhanced development characteristics. The application of glutamic acid resulted in greater plant height, leaf count, and dry weight of both stems and tops compared to the effects of proline spraying. The absence of irrigation at any growth stage in the study had no impact on the concentration of Chlorophyll (Ch. A and Ch. A + Ch. B). However, there was a modest effect on the concentrations of carotenoids and total Chlorophyll. Nevertheless, the concentration of (Ch. B) exhibited an increase during the fruiting phase under drought treatment. However, this rise needed to be more substantial to reach a statistically significant level. The ratio of Chlorophyll A to Ch. B increased exclusively during the dry period. The utilization of glutamic acid resulted in the highest levels of Ch.A, Ch.B total chlorophyll concentrations, with just a modest impact on carotenoid levels. In addition, the ratios of carotenoids in Ch. A and Ch. B, as well as the combined ratios of Ch.A and Ch.B exhibited similar reactions.

The role of supplemental lighting during late fall and winter on photosynthetic and non-photosynthetic pigments biosynthesis of cut rose flower (Rosa hybrida cv. ‘Dolce Vita’)

ABSTRACT Low levels of natural light within the late fall and winter periods are main restricting factors for greenhouse-cut rose flower production in northern countries. Here, the effects of supplemental lighting on photosynthetic and non-photosynthetic pigments and the morphological response of cut rose flower cv. ‘Dolce Vita’ were investigated. Four different supplemental lighting regimes, including 85, 170, 255, and 340 μmol·m−2·s−1 PPFD using a high-pressure sodium lamp for a six-hour day extension started at sunset were applied to rose plants during late fall and winter. With increasing light intensity to 255 μmol·m−2·s−1 PPFD, the content of chlorophyll a, total chlorophyll, carotenoid content, and the ratio of chlorophylls a/b as well as amount of anthocyanins greatly improved. The highest phenol content and total antioxidant capacity was observed in 170 μmol·m−2·s−1 PPFD. Moreover, extending of daylength by light intensity of 255 μmol·m−2·s−1 PPFD had a significant affirmative effect on traits of growth, including flower stem length (P < 0.01), leaf number (P < 0.05), renewal bud formation (P < 0.05), time of harvesting (P < 0.05), and vase life of cut flowers (P < 0.01). Considering physiological and morphological improvement, extending of daylength from 10-h to 16-h by supplemental light of 255 μmol·m−2·s−1 PPFD would be the best choice to cultivate cut rose flower cv. ‘Dolce Vita’.

Overexpression of ATP Synthase Subunit Beta (Atp2) Confers Enhanced Blast Disease Resistance in Transgenic Rice.

Previous research has shown that the pathogenicity and appressorium development of Magnaporthe oryzae can be inhibited by the ATP synthase subunit beta (Atp2) present in the photosynthetic bacterium Rhodopseudomonas palustris. In the present study, transgenic plants overexpressing the ATP2 gene were generated via genetic transformation in the Zhonghua11 (ZH11) genetic background. We compared the blast resistance and immune response of ATP2-overexpressing lines and wild-type plants. The expression of the Atp2 protein and the physiology, biochemistry, and growth traits of the mutant plants were also examined. The results showed that, compared with the wild-type plant ZH11, transgenic rice plants heterologously expressing ATP2 had no significant defects in agronomic traits, but the disease lesions caused by the rice blast fungus were significantly reduced. When infected by the rice blast fungus, the transgenic rice plants exhibited stronger antioxidant enzyme activity and a greater ratio of chlorophyll a to chlorophyll b. Furthermore, the immune response was triggered stronger in transgenic rice, especially the increase in reactive oxygen species (ROS), was more strongly triggered in plants. In summary, the expression of ATP2 as an antifungal protein in rice could improve the ability of rice to resist rice blast.

Effects of Exogenous 24-Epibrassinolide Leaves Spraying Application on Chlorophyll Accumulation and Gene Expression Profiles of Chlorophyll Metabolism in Celery

Celery is an important leaf vegetable crop in Apiaceae, of which the petiole and leaf blade are the main edible parts. The content and proportion of photosynthetic pigments, mainly chlorophyll, have an important effect on the growth and quality of celery. As a brassinosteroid (BR) plant hormone with high physiological activity, 24-epibrassinolide (24-EBL) has the physiological functions of promoting chlorophyll accumulation and delaying leaf senescence. To investigate the effects of 24-EBL treatment on chlorophyll accumulation at different growth stages of celery, celery plants (variety Ningqin NO. 1) were treated from 45~59 days after sowing (DAS), at intervals of 7 days, with two different concentrations of 24-EBL: 1.04 × 10−6 mol·L−1 and 1.67 × 10−6 mol·L−1. The content of chlorophyll and the expression levels of genes related to its metabolism were determined in celery leaf blades and petioles at three different stages (52, 59, 66 DAS). In the first stage (52 DAS), 1.04 × 10−6 mol·L−1 treatment of 24-EBL increased the expression levels of genes related to chlorophyll biosynthesis (AgHEML, AgCHLG, and AgCAO) to promote the accumulation of chlorophyll in leaf blades. During the second and third stages (59 and 66 DAS, respectively), 1.67 × 10−6 mol·L−1 24-EBL treatment induced the expression levels of genes related to chlorophyll cyclic regeneration (AgCLH) and inhibited the up-regulation of genes related to chlorophyll degradation (AgNYC, AgHCAR, and AgPPH) to promote chlorophyll (especially chlorophyll b) accumulation. These treatments regulated the ratio of chlorophyll a content to chlorophyll b content and changed the leaf color of the celery. The results show that leaf spraying with an appropriate concentration of 24-EBL can facilitate chlorophyll synthesis by promoting chlorophyll synthesis and cycling-related gene expression levels and increase chlorophyll content in the leaves of celery. This study provides a reference for exploring the specific function of 24-EBL in regulating chlorophyll content during the growth and development of celery.

Light on multicolor fluorescent carbon dots from a single biomass precursor through simply tuning the solvothermal temperature and time strategy

The conversion of biomass to carbon-based nanomaterials has recently received increasing attention, thanks to in line with the ideas of environmental protection and sustainable chemistry. Up to now, facial and fast synthesis of a single biomass precursor-derived carbon dots (CDs) with tunable multicolor fluorescence remains a challenge. Herein, we select mosses as cheap, abundant, and renewable biomass to prepare CDs with multicolor fluorescence by simply tuning solvothermal temperature and time. Through the characterization and comparison of a series of moss-derived CDs, it is revealed that the reaction temperature and time can effectively control the ratio of chlorophyll as the red luminescence center and carbon-core states as the blue luminescence center. Moreover, strong emission in the deep red light region, low toxicity, and outstanding biocompatibility made m-CD180 suitable for cellular imaging. This study provides a simple method for the green utilization of mosses and also provides a new idea for the fluorescence regulation and application of biomass-derived CDs.