Total Chlorophyll Content Research Articles

Influence of Electrical Conductivity on Plant Growth, Nutritional Quality, and Phytochemical Properties of Kale (Brassica napus) and Collard (Brassica oleracea) Grown Using Hydroponics

Kale (Brassica napus) and collard (Brassica oleracea) are two leafy greens in the family Brassicaceae. The leaves are rich sources of numerous health-beneficial compounds and are commonly used either fresh or cooked. This study aimed to optimize the nutrient management of kale and collard in hydroponic production for greater yield and crop quality. ‘Red Russian’ kale and ‘Flash F1’ collard were grown for 4 weeks after transplanting in a double polyethylene-plastic-covered greenhouse using a nutrient film technique (NFT) system with 18 channels. Kale and collard were alternately grown in each channel at four different electrical conductivity (EC) levels (1.2, 1.5, 1.8, and 2.1 mS·cm−1). Fresh and dry yields of kale increased linearly with increasing EC levels, while those of collard did not increase when EC was higher than 1.8 mS·cm−1. Kale leaves had significantly higher P, K, Mn, Zn, Cu, and B than the collard at all EC levels. Additionally, mineral nutrients (except N and Zn) in leaf tissue were highest at EC 1.5 and EC 1.8 in both the kale and collard. However, the changing trend of the total N and NO3- of the leaves showed a linear trend; these levels were highest under EC 2.1, followed by EC 1.8 and EC 1.5. EC levels also affected phytochemical accumulation in leaf tissue. In general, the kale leaves had significantly higher total anthocyanin, vitamin C, phenolic compounds, and glucosinolates but lower total chlorophylls and carotenoids than the collard. In addition, although EC levels affected neither the total chlorophyll or carotenoid content in kale nor glucosinolate content in either kale or collard, other important health-beneficial compounds (especially vitamin C, anthocyanin, and phenolic compounds) in kale and collard leaves reduced with the increasing EC levels. In conclusion, the kale leaf had more nutritional and phytochemical compounds than the collard. An EC level of 1.8 mS·cm−1 was the optimum EC level for the collard, while the kale yielded more at 2.1 mS·cm−1. Further investigations are needed to optimize nitrogen nutrition for hydroponically grown kale.

Green light enhances the phytochemical preservation of lettuce during postharvest cold storage.

The postharvest lighting environment is a main factor that influences quality preservation for harvested biomass. The objective of this study was to evaluate postharvest changes in bioactive compounds of lettuce with different storage light spectra. The effects of green LEDs with peaks at 500 nm and 530 nm, white LEDs (400-700 nm), and dark storage were evaluated, where light intensity (10 μmol m-2 s-1) and photoperiod (12 h per day) were constant with air temperature at 5°C over the 14 d treatment period. Lettuce stored with 500 nm and 530 nm green LEDs exhibited 1474.5% and 1451.8% (approximately 15.7 and 15.5 times) higher antioxidant activity, respectively, compared to dark storage. Significant improvements in total phenolic content, and 67.5% and 64.8% increases in total soluble solids with 530 nm and 500 nm green LEDs over dark storage were discerned. Exposure to 530 nm green LEDs led to 128.2% (approximately 2.28 times) higher anthocyanin content, a 26.2% increase in carotenoids, and a 95% rise in flavonoid content compared to dark storage. Increases of 26.4% and 16.0% in chlorophyll a content in lettuce stored under 500 nm and 530 nm green LEDs, respectively, and 65.6% and 46.6% rises in the Chlorophyll a/b ratio were observed. Compared to dark storage, green LEDs (500 nm) resulted in a 13.5% higher total chlorophyll content. Findings underscore the positive impact of green LEDs on the nutritional quality of lettuce, providing insight for postharvest practices.

Pectin Edible Films Filled with Ilex paraguariensis Concentrate Extract and Its Characterization

Ilex paraguariensis (IP) extract was added to prepare edible films using a central rotational composite design (CCRD) 22 with IP extract and sorbitol concentrations as variables. The IP extract was characterized by color parameters, total phenolic content, caffeine, flavonoids, and chlorophyll content, and antioxidant activity and the edible films were assessed for the same analysis and thickness, water vapor permeability (WVP), solubility in water, fluorescence, photodegradation and UV/Vis light barrier, FT-IR, thermogravimetry, and differential exploratory colorimetry. Sorbitol increased thickness and WVP, while the extract influenced the concentration of phenolic compounds in the films. The optimum concentrations of extract and sorbitol were 10% and 15%, respectively. Films presented thermal resistance (until 230 °C) and an excellent barrier to UV light. Furthermore, these films could carry compounds originally in IP, showing good functional properties concerning the water vapor barrier (showing a great variation scale due to the possibility to increase sorbitol or not, between 3.33 and 5.27 g mm/m2 day KPa). The films showed great potential to replace conventional primary packaging, and if consumed with food, as a bullet paper, they can add nutritional value to the packaged product.

Effect of Total Chlorophyll Content and Relative Water Content of Mini Tuber Potato under Aeroponic Condition in Jammu Region, India

The present study determine the effect of Total Chlorophyll Content and Relative Water Content of Mini Tuber Potato under Aeroponic Condition in Jammu Region, India. The adoption of new production technologies, usage of better varieties, quality seed material, good storage facilities, and transportation in recent years have helped to expand area, production, and productivity in India. The present study was conducted in the Division of Plant Physiology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu. The experiment was conducted during winter and spring seasons in 2022-23. Two varieties Kufri Badshah and Kufri Jyoti were taken as experimental material. Potato tubers were sown in net pots containing growing media and seedlings were transplanted at five leaves stage in the aeroponics system. The experiment was laid out in Completely Randomized Design with two treatments viz, T1 (cocopeat 100%) and T2 (cocopeat +vermiculite+ perlite+ vermicompost) in ratio (2:1:1:2) and after two weeks of transplanting data was recorded at three different stages of crop growth (20 DAT, 45 DAT and 80 DAT). The results clearly indicated that treatment T2 coco peat + perlite + vermiculite + vermicompost in the ratio of 2:1:1:2 was the most promising treatment for improving the, biochemical parameters, physical parameters and quality of both potato varieties when compared to other treatments.

Promoting tomato resilience: effects of ascorbic acid and sulfur-treated biochar in saline and non-saline cultivation environments

The resilience of tomato plants under different cultivation environments, particularly saline and non-saline conditions, was investigated by applying various treatments, including 0.5% Ascorbic Acid (AsA) and 1% Sulphur-treated Biochar (BS). The study evaluated parameters such as fruit length, diameter, yield per plant and pot, Total Soluble Solids (TSS) content, chlorophyll content, electrolyte leakage, enzyme activities (Superoxide Dismutase - SOD, Peroxidase - POD, Catalase - CAT), and nutrient content (Nitrogen - N%, Phosphorus - P%, Potassium - K%). Under saline conditions, significant enhancements were observed in fruit characteristics and yield metrics with the application of AsA and BS individually, with the combined treatment yielding the most substantial improvements. Notably, AsA and BS treatments exhibited varying effects on TSS levels, chlorophyll content, electrolyte leakage, and enzyme activities, with the combination treatment consistently demonstrating superior outcomes. Additionally, nutrient content analysis revealed notable increases, particularly under non-saline conditions, with the combined treatment showcasing the most significant enhancements. Overall, the study underscores the potential of AsA and BS treatments in promoting tomato resilience, offering insights into their synergistic effects on multiple physiological and biochemical parameters crucial for plant growth and productivity.

Comparative study of endophytic bacterial strains from non-host crops for enhancing plant growth and managing early blight in tomato

Bacillus pseudomycoides, Paenibacillus polymyxa, and B. velezensis are potent bacterial endophytes, which typically exhibit host-specific interactions. However, comparative studies of these endophytes in vitro and in planta in non-host crops are lacking. Therefore, in this study, we evaluated the potential of endophytes B. pseudomycoides strain HP3d, P. polymyxa strain PGSS1, B. velezensis strain A6, and P42, isolated from various crop ecosystems in promoting plant growth and inducing systemic resistance against early blight disease in tomato. In vitro, endophytes exhibited 44.44–55.56% and 37.50–87.50% inhibition of Alternaria solani in dual culture and volatilome bioassay, respectively. In the glasshouse, individual and combined applications via seed treatment (ST), seedling dip (SD), and foliar spray (FS) significantly enhanced shoot growth (23.63–57.61%), root growth (43.27–118.23%), number of leaves (77.52–93.58%), number of shoots (33.42–45.28%) and root dry matter (42.17–43.86%), reducing early blight (PDI) by 70.95–76.12% compared to uninoculated control. Enzymatic activities, including such as polyphenol oxidase (30–40 fold), peroxidase (65.00–75.00 fold), superoxide dismutase (34.20–37.20 fold) and phenylalanine ammonia-lyase (44.44–45.56 fold) were elevated post-inoculation in endophytes treated tomato plants challenged with A. solani compared to control treated only with A. solani and declined after the fifth day. The total chlorophyll content declined from the 0th to the 10th day, but endophyte treated plants exhibited lesser reductions (2.03–2.09) than uninoculated control. Field trials confirmed the glasshouse findings, showing reduced early blight and improved growth parameters in tomato where the ST + SD + FS combination emerged as the most effective treatment for all endophytes showing 1.06–1.88 fold increase in fruit yield per plant and 28.92–32.52% decrease in PDI compared to untreated control. Thus, the study highlights the broad-spectrum potential of these strains in promoting plant growth and controlling early blight in tomato, demonstrating non-host specificity. These endophytes offer eco-friendly alternatives to chemical pesticides, supporting sustainable agriculture. Their success in field trials suggests the potential for commercialization and large-scale use across diverse crops and pave the way for further interdisciplinary research to optimize their application in integrated pest management strategies.

Exploring the impact of aminoethoxyvinylglycine (AVG) on the ripening behaviour and quality of bananas under different storage conditions

ABSTRACT Bananas rapidly undergo physiological deterioration after harvest owing to their climacteric and perishable nature causing significant economic yield loss. Thus, the adoption of postharvest loss mitigation strategies becomes imperative for enhancing fruit longevity. This study aimed to assess the effect of postharvest treatment with different concentrations of aminoethoxyvinylglycine (AVG) on shelf life extension and quality sustainability of bananas, such as Grand Naine, Poovan and Ney Poovan, kept under ambient (27°C ± 2°C) and cool (17°C) conditions. The findings revealed that AVG-treated bananas reduced weight loss of banana hands (0.655–2.559 kg hand−1) and higher peel thickness (0.86–2.73 mm) and firmness (6.54–12.01 N) over untreated control at ambient storage condition, whereas under cool storage, weight loss of banana hands reduced from 0.761 to 2.579 kg hand−1, while both peel thickness (1.24–2.84 mm) and firmness (7.75–11.45 N) were retained for varieties. The physio-chemical traits of fruit, such as total chlorophyll and starch content, were improved due to AVG treatment under both storage conditions. Among the treatments, postharvest application of AVG at 700 ppm showed better performance in the morphological, physiological and quality characters irrespective of the varieties.

Comparative Analysis of Two Soybean Cultivars Revealed Tolerance Mechanisms Underlying Soybean Adaptation to Flooding

Flooding stress poses a significant challenge to soybean cultivation, impacting plant growth, development, and ultimately yield. In this study, we investigated the responses of two distinct soybean cultivars: flooding-tolerant Nanxiadou 38 (ND38) and flooding-sensitive Nanxiadou 45 (ND45). To achieve this, healthy seedlings were cultivated with the water surface consistently maintained at 5 cm above the soil surface. Our objective was to elucidate the physiological and molecular adaptations of the two cultivars. Under flooding stress, seedlings of both cultivars exhibited significant dwarfing and a notable decrease in root length. While there were no significant differences in the dry weight of aboveground shoots, the dry weight of underground shoots in ND38 was strikingly decreased following flooding. Additionally, total chlorophyll content decreased significantly following flooding stress, indicating impaired photosynthetic performance of the cultivars. Moreover, malondialdehyde (MDA) levels increased significantly after flooding, particularly in the ND45 cultivar, suggesting heightened oxidative stress. Expression analysis of methylation and demethylation genes indicated that MET1 and DME play crucial roles in response to flooding stress in soybeans. Meanwhile, analysis of the hemoglobin family (GLBs), aquaporin family (AQPs), glycolytic pathway-related genes, and NAC transcription factor-related genes identified GLB1-1 and GLB1-2, GLB2-2, PIP2-6, PIP2-7, TIP2-2, TIP4-1, TIP5-1, Gm02G222400 (fructose-bisphosphate aldolase), Gm19G017200 (glucose-6-phosphate isomerase), and Gm04G213900 (alcohol dehydrogenase 1) as key contributors to flooding tolerance in both soybean cultivars. These findings provide crucial insights into the physiological and molecular mechanisms underlying flooding tolerance in soybeans, which could guide future molecular breeding strategies for the development of flooding-tolerant soybean cultivars.

Effects of Biochar and Nitrogen Fertilizer Application Ratio on Leaf Physiology and Soil Characteristics of Bambusa tuldoides ‘Swolleninternode’

As one of the main bamboo species in coastal sandy land protection forests, Bambusa tuldoides ‘Swolleninternode’ can effectively improve the structure of forest tree species, increase the diversity of tree species and enhance the protection efficiency. However, research on the cultivation and utilization of B. tuldoides is still relatively scarce. Therefore, in this study, B. tuldoides was used as the research object. By applying biochar and nitrogen fertilizer, the effects of different biochar and nitrogen fertilizer ratios on the physiology and soil characteristics of bamboo were analyzed, and the optimal ratio scheme was identified. The results showed that the ratio of the T5 (A2B2C3) treatment had the best effect on the total chlorophyll, non-structural carbohydrate and nutrient contents of B. tuldoides leaves, and the contents under treatments was generally higher than under the control, CK. The activities of soil invertase, nitrate reductase and nitrite reductase were significantly increased under biochar treatment, and the effects of the T5 treatment were the best. The results of principal component analysis showed that the absolute values of the coefficient of leaf potassium, phosphorus content and soil total nitrogen were larger and more important, and the comprehensive evaluation of the T5 treatment was the highest.

Combined Toxicity of Multi-Walled Carbon Nanotubes and Cu2+ on the Growth of Ryegrass: Effect of Surface Modification, Dose, and Exposure Time Pattern.

The escalating release of multi-walled carbon nanotubes (MWCNTs) into the environment has raised concerns due to their potential ecotoxicological impacts. However, their combined phytotoxicity with heavy metals such as copper (Cu) is still unclear. This study investigated the individual and combined toxic effects of MWCNTs (MWCNT, MWCNT-OH, and MWCNT-COOH) and Cu2+ on ryegrass (Lolium multiflorum), uniquely considering different addition orders. The results show that Cu severely inhibited the growth of ryegrass while MWCNTs exhibited a hormesis effect on ryegrass. When MWCNT and Cu were combined, the malondialdehyde (MDA) content in ryegrass showed a 32.39% increase at 20 mg/L MWCNT exposure, suggesting reduced oxidative stress. However, at the higher concentration of 1000 mg/L, it led to a significant 75.22% reduction in ryegrass biomass. MWCNT-COOH had the most pronounced effect, reducing the total chlorophyll content by 39.76% compared to unmodified MWCNT and by 10.67% compared to MWCNT-OH (500 mg/L). Additionally, pre-induced MWCNTs might alleviate the Cu in the plant by 23.08-35.38% through adsorption in the nutrient solution. Small molecule organic acids and amino acids primarily mediated the response to environmental stress in ryegrass. This research provides crucial insights into understanding the complex interactions of MWCNT and Cu2+ and their combined effects on plant ecosystems.

Physiological Behavior of Rubber Plants (<i>Hevea Brasilliensis</i>) to Different Soil Moisture Conditions

Drought conditions can severely impact rubber (<i>Hevea brasiliensis</i>) plantations, leading to economic loss in Malaysia. The study aimed to assess the impact of varying soil moisture levels on the physiological characteristics of five latex timber clones (LTCs) of rubber, with the goal of identifying the most suitable clone for specific soil moisture conditions. These conditions include (1) field capacity, (2) 75% available water (AW), (3) 50% AW, (4) 25% AW, and (5) wilting point, with the ultimate objective of optimizing cultivation methods and fostering sustainable rubber production in Malaysia. The five clones under investigation include RRIM3001, RRIM2025, RRIM2001, RRIM928, and PB350. Leaf chlorophyll content, stomatal conductance, and net photosynthesis were measured 4 and 8 months after treatment (MAT). The findings indicated significant effects of moisture stress on various physiological attributes, including total chlorophyll content, relative chlorophyll content, stomatal conductance, and net photosynthesis rate. At 4 and 8 MATs, the clones subjected to field capacity exhibited the highest values for these physiological characteristics, followed by those exposed to 75% available water, with the lowest values observed at the wilting point. RRIM3001 consistently exhibited the highest total chlorophyll content, stomatal conductance, and net photosynthesis among the clones at both sampling dates. The highest net photosynthesis was observed in the RRIM3001 clone under field capacity conditions. Furthermore, a significant positive correlation was identified between total chlorophyll and relative chlorophyll contents, as well as between net photosynthesis and stomatal conductance. These findings carry practical implications for water management during the initial growth phase of rubber seedlings and for replanting initiatives in rubber plantations.

Enhancing salt tolerance in rice genotypes through exogenous melatonin application by modulating growth patterns and antistress agents

Melatonin is a bioactive molecule with an important role in plants responding to various abiotic and biotic stresses. This study aims to determine the role of melatonin in rice under salt stress. This study used a factorial completely randomized design. The first factor was local rice varieties (IR64 and Silaun), and the second factor was plant treatments (control, 1 µM melatonin, 150 mM NaCl, 150 mM NaCl + 1µM melatonin). This study shows that exogenous melatonin can increase plant growth, such as plant height, root length, stem length, leaf length, leaf area, and plant biomass under salt stress compared to treatment without melatonin. Exogenous melatonin can increase the total chlorophyll content, relative water content, and proline content, reduce the total sodium content, and increase potassium absorption under conditions of salinity stress. Melatonin is also able to scavenge ROS in plants, resulted the decrease in ROS and MDA content. In terms of gene expression, OsAPX1 and cytosolic APX exhibited the highest expression in IR64 under combined salt and melatonin treatment, while GPOD, Mn-SOD, and Cu/Zn-SOD were upregulated under various conditions in both varieties. Additionally, OsLEA showed high expression in both varieties under control conditions, and CAT was significantly upregulated under salt stress. Our findings indicate that exogenous melatonin has the potential to enhance various factors under salt stress and helping in the recovery of rice plants from sodium (Na+) damage.

Use of nanocelluloses from orange peel and ZnO as hybrid nanofiller in developing functionalized starch nanocomposite for edible coatings

AbstractThis study explores the formulations of orange peel nanocelluloses (NC) with tailored dimensions for the development of functionalized nanocomposites coatings on green chilies. In the present century, the valorization of agro‐waste, specifically orange peel for developing NC facilitated sustainable packaging such as edible films and coatings with improved properties has received importance. As, this approach aligns with the sustainable development goals, including reduced food waste and agro waste. For the work, the derived orange peel celluloses were acid hydrolyzed using sulfuric acid (H2SO4) and hydrochloric acid (HCl) to deliver cellulose nanofibers (CNF) and cellulose nanoparticles (CNP), respectively. The fabricated CNP and CNF were characterized using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and thermogravimetric analysis (TGA). The FESEM morphology showed the formation of CNP with diameter ranges from 42.4 to 108 nm and formation of CNF with diameter ranged from 27.4 to 50.5 nm. The creation of the functionalized nanocomposite was done by reinforcing with hybrid nanofillers consisting CNF, CNP consecutively with ZnO in corn starch for tailormade packaging properties in terms of mechanical, physicochemical, optical, thermal properties, and so on. The results reveal improved tensile strength, and reduced water vapor transmission rates of nanocomposite with the addition of hybrid nanofillers. Additionally, green chilies were coated with the functionalized nanocomposites prepared by different concentrations of nanofillers. The storage analysis was performed in terms of weight loss, total chlorophyll content, and microbiological analysis. The developed coatings were found to be effective in extending the shelf life of green chilies. The control samples showed significantly higher weight loss compared to coated ones. The coated samples showed significantly better firmness and total chlorophyll content after 20 days of storage. In comparison to other coatings, NC and ZnO incorporated starch‐based coating was found to be the most effective in maintaining the quality of fresh green chilies throughout the storage. Thus, incorporating NC and ZnO in starch‐based films and coatings presents a promising avenue for sustainable packaging and preservation.Highlights Agro‐waste orange peel was valorized to develop sustainable food packaging. Orange peel‐based nanocellulose was developed using H2SO4 and HCl. Nanocomposite film was developed using hybrid nanofillers. Nanocomposites provide tailored properties due to the nanofillers. Developed nanocomposite was used as edible coatings on green chilies.

Contrasting Alleles of OsNRT1.1b Fostering Potential in Improving Nitrogen Use Efficiency in Rice.

Nitrogen use efficiency (NUE) is important for the growth and development of rice and is significant in reducing the costs of rice production. OsNRT1.1b is involved in nitrate assimilation, and the alleles at position 21,759,092 on chromosome 10 clearly separate indica (Pathum Thani 1 (PTT1) and Homcholasit (HCS)) and japonica (Azucena and Leum Pua (LP)) rice varieties. Rice morphological and physiological traits were collected at three nitrogen levels (N0 = 0 kg ha-1, N7 = 43.75 kg ha-1, and N14 = 87.5 kg ha-1). Leaf and tiller numbers in PTT1 and HCS at N7 and N14 were two to three times higher than those at N0. At harvest, the biomass yield in PTT1 was the highest, while the total grain number in HCS was the maximum. The leaf widths and total chlorophyll contents (SPAD units) of Azucena and LP increased with nitrogen application as well as photosynthetic pigment parameters; for example, plant senescence reflectance indices (PSRIs), structure-insensitive pigment indices (SIPIs), and modified chlorophyll absorption ratio indices (MCARIs) were highly related in the japonica varieties. PTT1 and HCS, both carrying the A allele at OsNRT1.1b, had better NUE than Azucena and LP with the G allele. HCS, overall, had better NUE than PTT1. The translation to grain yield of assimilates was remarkable in PTT1 and HCS compared with Azucena and LP. In addition, HCS converted biomass for a 75% higher yield than PTT1. The ability of HCS to produce high yields was achieved even at N7 nitrogen fertilization, manifesting efficient use of nitrogen.

Morpho-biochemical and molecular characterization of new mung bean [Vigna radiata (L.) Wilczek] landraces for Cercospora leaf spot (CLS) disease resistance

Mung bean production is significantly lowered by Cercospora leaf spot (CLS) in various parts of the globe. The most effective way to increase mung bean resilience to this stress is to identify new CLS resistance sources. Therefore, a panel population of 13 landraces along with 2 susceptible check cultivar, and 11 SSR markers were taken for the present experiment. Correlation analysis suggested significant relationships between the quantitative traits, retained resistance (Banapur local, and Kalampur local), and moderately resistance (Dikhitapada local, and Fakirpur local 1) to CLS. However, total chlorophyll content (TCL) showed strong positive correlations with phenolic content (PHE) (0.984), peroxidase activity (POX) (0.931), and polyphenol oxidase activity (PPO) (0.969). Moreover, PHE (−0.769) and POX (−0.867) were also found negatively correlated with CLS disease reaction. The eigenvalues from the principal component analysis (PCA) indicated the first three principal components collectively explained 84.88 % of the total variance. Molecular analysis of the panel population suggested a PIC value range from 0.30 to 0.88, with an average 0.696, and markers such as cp01713 (0.84), cp02181 (0.87), and CEDG147 (0.88) had higher PIC values. Principal coordinate analysis (PCoA) suggested capturing of 69.06 % of the total variance by the first three axes, and the landraces were categorizing into three clusters (cluster A, B and C). The genetic distances among the landraces ranged from 0 to 0.608, and phylogenetic tree differentiated them into three major clusters at respective Jaccard's similarity coefficient i.e., Cluster I (0.68), II (0.75) and III (0.83). Meanwhile, the resistance and moderately resistance landraces were observed in cluster A and cluster B, and in cluster II and cluster III respectively. The resistance landraces obtained from the present study could be used as potential donor for breeding process towards CLS resistance in mung bean.

An assessment of in vitro lead (Pb) bioaccumulation of Dianthus chinensis L. (Chinese pink).

Heavy metals (HM) also known as potentially toxic elements (PTEs), are well-known environmental pollutants, among which lead (Pb) is a widespread and hazardous soil contaminant. Its removal from soil sediments is often difficult to achieve. In this study, in vitro experiments were conducted to investigate the bioaccumulation capability of Dianthus chinensis L. in solid and liquid Murashige and Skoog (MS) medium supplemented with varying concentrations (0, 10, 100, and 200µM) of Pb as lead nitrate [Pb(NO3)2] for 30days. The objectives of the study were to assess the efficiency of the selected plant as a bio-accumulator in the in vitro system and to obtain data on morphological, biochemical, and molecular changes during Pb salt-induced stress. Significant growth patterns of initial growth promotion up to 100µM lead nitrate supplemented medium were observed, with maximum shoot length and biomass production along with remarkable lead bioaccumulation. Molecular studies on in vitro raised plantlets confirm the high degree of genetic uniformity (98.3%) of the selected plants after a considerable duration (30days) of Pb exposure. Biochemical parameters revealed significant stress effects, including a 284% reduction in total chlorophyll content, altered carotenoid, and proline level during the study. The experiment revealed the high tolerance capacity of D. chinensis to Pb salt and its bioaccumulation potential (397.33mg/kg). This increases the possible use of such an ornamental and floriculture plant as a prospective candidate for the efficient removal of soil Pb pollutants, as they can remediate soils, coupled with aesthetic and profitable outcomes for the growers.

Phytochemical and morpho-physiological response of Melissa officinalis L. to different NH4+ to NO3̄ ratios under hydroponic cultivation

BackgroundThe utilization of nutrition management, has recently been developed as a means of improving the growth and production of phytochemical compounds in herbs. The present study aimed to improve the growth, physiological, and phytochemical characteristics of lemon balm (Melissa officinalis L.) using different NH4+ (ammonium) to NO3̄ (nitrate) ratios (0:100, 25:75, 50:50, 75:25 and 100:0) under floating culture system (FCS).ResultsThe treatment containing 0:100 - NH4+:NO3̄ ratio showed the most remarkable values for the growth and morpho-physiological characteristics of M. officinalis. The results demonstrated that maximum biomass (105.57 g) earned by using the ratio of 0:100 and minimum at 75:25 ratio of NH4+: NO3̄. The plants treated with high nitrate ratio (0:100 - NH4+:NO3̄) showed the greatest concentration of total phenolics (60.40 mg GAE/g DW), chlorophyll a (31.32 mg/100 g DW), flavonoids (12.97 mg QUE/g DW), and carotenoids (83.06 mg/100 g DW). Using the 75:25 - NH4+:NO3̄ ratio caused the highest dry matter (DM), N and K macronutrients in the leaves. The highest antioxidant activity by both DPPH (37.39 µg AAE/mL) and FRAP (69.55 mM Fe++/g DW) methods was obtained in 75:25 - NH4+:NO3̄ treatment. The p-coumaric acid as a main abundant phenolic composition, was detected by HPLC analysis as the highest content in samples grown under 0:100 - NH4+:NO3̄ treatment. Also, the major compounds in M. officinalis essential oil were identified as geranial, neral, geranyl acetate and geraniol by GC analysis. With increasing NO3̄ application, geraniol and geranyl acetate contents were decreased.ConclusionsThe findings of present study suggest that the management of NH4+ to NO3̄ ratios in nutrient solutions could contribute to improving growth, physiological and phytochemical properties of M. officinalis. The plants treated with high nitrate ratio (especially 0:100 - NH4+:NO3̄) showed the greatest effects on improving the growth and production of morpho-physiological and phytochemical compounds. By comprehensively understanding the intricate dynamics among nitrogen sources, plants, and their surroundings, researchers and practitioners can devise inventive approaches to optimize nitrogen management practices and foster sustainable agricultural frameworks.

Quantifying the Impact of Nitrogen Concentration Variations on Quality Characteristics of Soilless Cultivated Cherry Tomato

Within the domain of macronutrients, nitrogen has garnered significant recognition as a pivotal element due to its profound influence on both the vegetative growth and quality attributes of a crop. An abundance of scientific research has consistently demonstrated that attaining optimal productivity necessitates the meticulous management of soil moisture availability, complemented by the timely provision of nitrogen during critical growth stage intervals. The study aimed to optimize the nitrogen concentration in a hydroponic solution by testing a range of concentrations. The objective was to systematically examine the effects of different nitrogen levels and determine the optimal concentration for the desired outcomes. The assessment was carried out in a meticulously controlled greenhouse environment from October 2019 to April 2021, with the primary objective of systematically investigating the impact on quality characteristics specific to the rosa variety of cherry tomato. To investigate the effects of different nitrogen concentrations, four distinct levels of 4 mM, 6 mM, 8 mM, and 10 mM per litre of nutrient solution were employed. The nitrogen source consisted of a combination of NO3- and NH4+, with a ratio of 40:60, respectively. The nutrient solution with an 8 mM nitrogen concentration exhibited a significantly augmented effect on increasing the equatorial and polar diameter of fruits, average fruit weight, pericarp thickness, as well as the accumulation of total chlorophyll, ascorbic acid, lycopene, β-carotene, and total soluble solids (TSS) content. These findings demonstrate the pronounced and positive influence of the 8 mM nitrogen concentration on the aforementioned quality characteristics.

Circular Utilization of Coffee Grounds as a Bio-Nutrient through Microbial Transformation for Leafy Vegetables

This study explores the production of bio-nutrients from bioactive compound-rich spent coffee grounds (SCG) and biochar (BC) through composting after inoculation with a biological agent and its impact on the growth performance of garden cress and spinach. The SCG was composted with six doses of BC (0, 5, 10, 15, 20, and 25%). The compost with 10% BC exhibited the best maturity, humification, and phytotoxicity index values of dissolved organic carbon (DOC), humification index (E4/E6), and germination index (GI). A metagenome analysis showed that compost starter enhanced the bacterial community’s relative abundance, richness, and diversity in SCG and BC treatments. This improvement included increased Patescibacteria, which can break down noxious phenolic compounds found in SCG and BC. The BC enriched the compost with phosphorus and potassium while preserving the nitrogen. In plant growth experiments, the total chlorophyll content in compost-treated garden cress and spinach was 2.47 and 4.88 mg g−1, respectively, which was significantly greater (p ≤ 0.05) than in unfertilized plants and similar to the plants treated with traditional fertilizer. Overall, the results show that the compost of SCG + BC was well-suited for promoting the growth of garden cress and spinach, providing adequate nutrients as a fertilizer for these leafy vegetables.

Nutritional Composition and Phytochemical Analysis of Ragi Microgreens

Ragi (elusine coracana) is one of the staple pseudocereal well known for his multitude of beneficial roles in promoting health and general wellbeing. Though it is one of the common millets and majorly consumed in south and north part of India, nutritional potential of ragi microgreens is yet to be explored. Considering other established microgreen’s nutritional significance, possible health implications, antioxidant properties and erythropoietic activity, present study was undertaken to estimate nutritional composition, qualitative phytochemical analysis, and quantification of bioactive ingredients of lyophilized ragi microgreens. Since lyophilisation is considered superior technique in preserving heat labile compounds, compared to other dehydration methods, it was used as the preferred sample for present study. Nutrient composition of ragi microgreens was found to be impressive with a protein content of 13.3 gm percent, crude fibre content 8 gm percent, iron mg percent vitamin C 112 mg percent and calcium are 91 gm percent. Preliminary phytochemical screening revealed presence of terpenoids, alkaloids, flavonoids, tannins, and sterols. Total chlorophyll estimation indicated that total chlorophyll content of lyophilized ragi microgreen is 623 mg/100 gm.