Copper (Cu) is a toxic metal that accumulates in soil due to agricultural and industrial activities, potentially impacting plant growth and productivity. Our study examined the phytotoxic effects of Cu on Vigna radiata L. by exposing plants to a series of Cu concentrations (1, 4 and 7 mM) under controlled conditions. Growth parameters, photosynthetic performance, biochemical traits, and oxidative stress indicators were analyzed in 21-day-old Cu-treated plants and compared with control plants. The results demonstrated a concentration-dependent decline in shoot and root biomass, relative water content (RWC), pigment content, photosynthetic efficiency, carbohydrates, and lipid content. Conversely, oxidative stress markers such as malondialdehyde (MDA), electrolyte leakage, superoxide dismutase (SOD) and ascorbate peroxidase (APX) activity and proline accumulation increased significantly with increasing Cu concentrations, indicating cellular damage. Notably, protein levels increased with increased Cu concentrations, which may contribute to their tolerance to metal stress, however, it was insufficient to mitigate stress. Further research is needed to validate these findings and explore the mechanisms underlying copper stress tolerance.
Background Fungal infection predominantly damages agricultural practices, and conventional chemical fungicides and insecticides are applied to control it, which extensively harms human health and the environment. Some bacterial species can control fungus by lysing its outer chitin layer.Objectives The present research aimed to isolate microorganisms capable of producing chitinase, thus acting as a highly effective biocontrol agent in combating fungal phytopathogens.Methods Two chitinase-producing bacterial strains were successfully isolated and screened from soil samples from a fish market environment. The process involved the aseptic collection of soil samples, followed by serial dilution to facilitate microorganism isolation. The bacterium exhibited optimal extracellular chitinase enzyme production following a 72-h incubation period at a temperature of 30 degrees C in a chitinase detection medium containing 0.5% chitin. Validation of chitinase production was confirmed through a clear zone assay, thus verifying its chitinase-producing capacity.Results Among the various isolated strains, isolates S3C1 and S3C3 demonstrated the highest chitinase activity, leading to their selection for further investigation. Comprehensive morphological and biochemical tests were conducted on these two isolates to assess their characteristics and capabilities. These tests established that both isolates were gram-negative, rod-shaped bacteria. Through genetic sequencing of the 16S rRNA gene, both organisms were identified as Klebsiella variicola exhibiting a remarkable similarity of 99% with S3C1 and S3C3 respectively. The bacteria exhibited maximum chitinase synthesis at optimal circumstances, which were determined to be a temperature of 30 degrees C and a pH of 7, after a 48-h incubation period. The bacteria exhibited robust antifungal activity during bioassays, demonstrating their capability to suppress the growth of fungal pathogens (specifically, Fusarium oxysporum) in vitro.Conclusion This research suggests a promising alternative to synthetic fungicides in agricultural practices, fostering a sustainable approach to disease management.
The study examines the toxicity of cadmium (Cd), microplastics (MPs) and their combined pollution on wheat plants, focusing on Cd accumulation and alterations to soil physical and chemical properties. To provide guidance for understanding the physiological and ecological responses of wheat to Cd and MPs contamination. Using a soil pot experiment, the individual and combined impacts of Cd (0 mg kg(-)(1) and 5 mg kg(-)(1)) and polyvinyl chloride microplastics (PVC-MPs) (0%, 0.5%, 1.0%, and 5.0%) on various aspects of wheat growth were assessed. Partial least square (PLS) model was employed to analyze the quantitative relationship between wheat growth indicators and various physicochemical parameters. Results revealed that the PVC-MPs significantly suppressed wheat growth parameters, photosynthetic efficiency, and chlorophyll content. As the level of contamination increased, the damage to wheat chloroplasts became more severe, leaf thickness reduced, and canopy temperatures rose. Conversely, root morphology parameters and Cd accumulation in wheat plants exhibited a declining trend. Moreover, soil fertility indicators and the activities of soil urease, acid phosphatase and dehydrogenase increased in correlation with higher concentrations of PVC-MPs. The PLS model identified stomatal conductance as the critical controlling factor influencing wheat growth under the combined stress of PVC-MPs and Cd. Overall, co-occurring Cd and PVC-MPs can change wheat plant performance and soil traits. These findings provide crucial insights into the physiological and ecological impacts of Cd and microplastic co-pollution in wheat-soil systems.
Saline-alkaline stress is a common problem in Akebia trifoliata cultivation. In this study, the enhancing effects of 5-azacytidine (5-AzaC) on the resistance of A. trifoliata to saline-alkaline stress and the underlying mechanisms were investigated. Plant height, stem diameter, biomass, root length, fresh weight of root, and root/shoot ratio of 6-month-old A. trifoliata seedlings were measured after saline-alkaline stress with or without 5-AzaC treatment. Moreover, the contents of photosynthetic pigments, malondialdehyde (MDA), H2O2, sodium, soluble sugar, and proline; activities of superoxide dismutase, peroxidase (POD), and catalase (CAT); and anatomical structures of root, stem, and leaf were assessed. Furthermore, comparative transcriptome sequencing was performed. The results demonstrated that growth and development of A. trifoliata were severely inhibited under saline-alkaline stress, suggesting that the seedlings were exposed to severe oxidative and osmotic stresses. Treatment with exogenous 5-AzaC could significantly relieve the symptoms of saline-alkaline stress in A. trifoliata. Under saline-alkaline stress, 5-AzaC could increase the stem diameter, biomass, root length, fresh weight of root, and root/shoot ratio and minimize damages to the anatomical structure. Moreover, absorption of Na+ was reduced; ionic balance was maintained; POD and CAT activities were significantly improved; proline and soluble sugar contents increased, and H2O2 and MDA contents decreased. Transcriptome analysis revealed that 5-AzaC functioned via regulating KEGG pathways such as plant hormone signal transduction, phenylpropanoid biosynthesis, photosynthesis, amino sugar and nucleotide sugar metabolism, and glutathione metabolism under saline-alkaline stress. Particularly, enhanced expression of genes from the auxin pathway in plant hormone signal transduction; the lignin synthetic pathway in phenylpropanoid biosynthesis; and photosystem II, photosystem I, photosynthetic electron transport, and F-type ATP pathway in photosynthesis may be related to 5-AzaC-induced saline-alkaline resistance. The results provided theoretical references for A. trifoliata cultivation in saline-alkaline soil and application of 5-AzaC to improve saline-alkaline tolerance in plants.
Rubber-based intercropping is a recommended practice due to its ecological and economic benefits. Understanding the implications of ecophysiological changes in intercropping farms on the production and technological properties of Hevea rubber is still necessary. This study investigated the effects of seasonal changes in the leaf area index (LAI) and soil moisture content (SMC) of rubber-based intercropping farms (RBIFs) on the latex biochemical composition, yield, and technological properties of Hevea rubber. Three RBIFs: rubber-bamboo (RB); rubber-melinjo (RM); rubber-coffee (RC), and one rubber monocropping farm (RR) were selected in a village in southern Thailand. Data were collected from September to December 2020 (S1), January to April 2021 (S2), and May to August 2021 (S3). Over the study period, RB, RM, and RC exhibited significantly high LAI values of 1.2, 1.05, and 0.99, respectively, whereas RR had a low LAI of 0.79. The increasing SMC with soil depths was pronounced in all RBIFs. RB and RM expressed less physiological stress and delivered latex yield, which was on average 40% higher than that of RR. With higher molecular weight distributions, their rheological properties were comparable to those of RR. However, the latex Mg content of RB and RM significantly increased to 660 and 742 mg/kg, respectively, in S2. Their dry rubbers had an ash content of more than 0.6% in S3.
The application of biochar as a soil amendment has gained increasing attention due to its potential to improve soil properties, enhance plant growth, and mitigate environmental stresses. This study aims to evaluate the effects of different biochar treatments-wood biochar (WBc), vegetable biochar (VBc), and a mixture of wood and vegetable biochar (WVBc)-on the growth, physiological, and biochemical responses of Pisum sativum L. seedlings. A greenhouse experiment was conducted to evaluate the effects of biochar treatments-wood biochar (WBc), vegetable biochar (VBc), and a mixture of wood and vegetable biochar (WVBc)-on Pisum sativum L. seedlings. Seedlings were grown under controlled conditions, and various growth, physiological, and biochemical parameters were assessed, including plant biomass, photosynthetic efficiency, nutrient content, oxidative stress markers, and antioxidant defense responses. The findings revealed significant improvements across several plant growth metrics, including root and shoot lengths, fresh and dry biomass, with WVBc showing the most pronounced effects. Root length increased by 75.45%, shoot length by 32.4%, and shoot fresh weight by 43.4% compared to the control. Photosynthetic parameters also improved, with total chlorophyll content increasing by 50.1%, net photosynthetic rate by 28.3%, RWC by 17.0%, and WUE by 22.5% under WVBc treatment. Enhanced photosynthesis was attributed to higher nitrogen availability and improved soil moisture retention. Biochemical analyses indicated significant increases in total protein and carbohydrate content, with WVBc treatment yielding the highest gains. Additionally, glycine betaine (GB) production increased by 44.7%, while proline content decreased by 46.1%, suggesting improved stress tolerance. The reduction in oxidative stress markers (MDA and H2O2) further supports the role of biochar in mitigating oxidative damage. Moreover, biochar treatments enhanced the activities of key antioxidant enzymes and increased levels of non-enzymatic antioxidants such as reduced glutathione (GSH), ascorbic acid (AsA), and alpha-tocopherol, thereby boosting the plants' antioxidant defenses. The WVBc treatment significantly enhanced nutrient uptake, particularly nitrogen, potassium, and phosphorus, contributing to improved mineral content and plant health. Overall, this study highlights mixed wood-vegetable biochar (WVBc) as an effective soil amendment that enhances plant resilience, nutrient use efficiency, and crop productivity, offering a promising strategy for sustainable agriculture and stress mitigation.
This study evaluated the physiological responses, hormonal signaling, osmotic and nutrient levels, as well as the performance of essential oils, antioxidant enzymes, and secondary metabolites in Lavender plants subjected to chromium and fluoride toxicity and biochar application. The findings indicated that the administration of raw and especially multiple-chemical engineered biochars decreased fluoride (about 16-40%) and chromium (39-60%) levels in Lavender leaves, whereas raised CEC and soil pH, nitrogen (10-37%), potassium (20-47%), phosphorus (10-60%), magnesium (30-49%), calcium (20-50%), zinc (39-240%), iron (40-120%), plant biomass, and photosynthetic pigments of Lavender plant leaves under toxic fluoride and chromium conditions. The treatments with multiple-chemical engineered biochars decreased the osmotic stress and osmolyte concentration (carbohydrates, soluble proteins, and proline) in the leaves of Lavender plants. Both raw and multiple-chemical engineered biochars significantly enhanced the water content of plant leaves, reaching up to 10% under toxic circumstances. Moreover, these treatments decreased the synthesis of stress hormones such as jasmonic acid (4-17%), salicylic acid (29-49%), and abscisic acid (30-66%), while increasing the production of Indole-3-acetic acid (IAA) (15-29%) in Lavender plants subjected to chromium and fluoride stress. The use of multiple-chemical engineered biochars showed notable efficacy in enhancing antioxidant enzyme's activity against oxidative damage induced by metal toxicity and decreasing proline accumulation. Maximum concentrations of linalyl acetate, borneol, camphor, and linalool were achieved under fluoride and chromium stress conditions by metaphosphoric acid-engineered biochar. Multiple-chemical engineered biochars application can be inferred as valuable approach to enhance both the quality and quantity of lavender essential oil under conditions of fluoride and chromium-induced stress.
Remotely sensed top-of-the-canopy (TOC) SIF is highly impacted by non-physiological structural and environmental factors that are confounding the photosystems' emitted SIF signal. Our proposed method for scaling TOC SIF down to photosystems' (PSI and PSII) level uses a three-dimensional (3D) modeling approach, capable of accounting physically for the main confounding factors, i.e., SIF scattering and reabsorption within a leaf, by canopy structures, and by the soil beneath. Here, we propose a novel SIF downscaling method that separates the structural component from the functional physiological component of TOC SIF signal by using the 3D Discrete Anisotropic Radiative Transfer (DART) model coupled with the leaf-level fluorescence model Fluspect-CX, and estimates the Fluorescence Quantum Efficiency (FQE) at photosystem level. The method was first applied on in- situ diurnal measurements acquired at the top of the canopy of an alfalfa crop with a near-distance point- measuring FloX system. The retrieved photosystem-level FQE diurnal courses correlated significantly with photosynthetic yield of PSII measured by an active leaf florescence instrument MiniPAM (R = 0.87, R2 = 0.76 before and R =-0.82, R2 = 0.67 after 2.00 pm local time). Diurnal FQE trends of both photosystems jointly were descending from late morning 9.00 am till afternoon 4.00 pm. A slight late-afternoon increase, observed for three days between 4.00 and 7.00 pm, could be attributed to an increase in FQE of PSI that was retrieved separately from PSII. The method was subsequently extended and applied to airborne SIF images acquired with the HyPlant imaging spectrometer over the same alfalfa field. While the input canopy SIF radiance computed by two different methods, i) a spectral fitting method (SFM) and ii) a spectral fitting method neural network (SFMNN), produce broad and irregularly shaped (skewed) histograms (spatial coefficients of variation: CV = 29-35 % and 14-20 %, respectively), the retrieved HyPlant per-pixel FQE estimates formed significantly narrower and regularly bell- shaped near-Gaussian histograms (CV = 27-34 % and 14-17 %, respectively). The achieved spatial homogeneity of resulting FQE maps confirms successful removal of the TOC SIF radiance confounding impacts. Since our method is based on direct matching of measured and physically modelled canopy SIF radiance, simulated by 3D radiative transfer, it is versatile and transferable to other canopy architectures, including structurally complex canopies such as forest stands.
Amylase has numerous applications in the processing food sector, including brewing, animal feed, baking, fruit juice manufacturing, starch syrups, and starch liquefaction. Practical applications have been the primary focus of recent research on novel properties of bacterial alpha-amylases. Many amylolytic-active bacterial isolates were obtained from samples of organic-rich, salinity-rich soil. Morphological and 16S rRNA gene sequence studies clearly revealed that the organism belongs to Bacillus sp. and was named Bacillus cereus strain GL2 (PP463909.1 (When pH 6.0, 45 degrees C, and 12 hours of incubation were met the optimal growth conditions for the strain produced the highest amount of alpha-amylase activity. B. cereus strain GL2 alpha-amylase isoenzyme was purified to homogeneity using Sephacryl (TM) S-200 chromatography and ammonium sulfate precipitation. The electrophoretic molecular weight of B. cereus alpha-amylase was 58 kDa. The optimal pH and temperature for measuring alpha-amylase activity were 50 degrees C and 6.0, respectively. alpha-Amylase did not change at 50 degrees C. The purified enzyme improves bread texture by reducing stiffness while improving cohesiveness and flexibility. Purified alpha-amylase was added to the flour, which improved the rheological properties and overall bread quality. As a result, the alpha-amylase from B. cereus strain GL2 can be used to promote bread-making.
Nano-biochar considers a versatile and valuable sorbent to enhance plant productivity by improving soil environment and emerged as a novel solution for environmental remediation and sustainable agriculture in modern era. In this study, roles of foliar applied nanobiochar colloidal solution (NBS) on salt stressed tomato plants were investigated. For this purpose, NBS was applied (0%, 1% 3% and 5%) on two groups of plants (control 0 mM and salt stress 60 mM). Tween-20 was used as a surfactant to prolong NBS effective stay on plant leaf surface. The results showed that 3% NBS application effectively improved the plant height, plant biomass, fruit count and fruit weight under non-stressed and stressed plants. In addition, 3% NBS application further increased the plant pigments such as chlorophyll by 72% and 53%, carotenoids by 64% and 40%, leaf relative water content by 4.1 fold and 1.07 fold under both conditions, respectively. NBS application stabilized the plasma membrane via reducing electrolyte leakage by 30% as well as reduced the lipid peroxidation rates by 46% and 29% under non-stressed and stressed plants, respectively. 3% NBS application also significantly enhanced the plants primary and secondary metabolites, as well as activities of antioxidant enzymes compared to control plants. Overall, NBS foliar application significantly improved all growth and yield indices, pigments, primary and secondary metabolites, leaf water content, antioxidant enzyme activities as well as reduced electrolyte leakage and lipid peroxidation rates in tomato to combat stress conditions. In future, studies on nano biochar interactions with soil microbiota, surface modifications, long-term environmental impacts, reduced methane gas emissions, and biocompatibility could provide insights into optimizing its use in sustainable agriculture.