Acid Phosphatase Activity Research Articles

NaCl Modifies Biochemical Traits in Bacterial Endophytes Isolated from Halophytes: Towards Salinity Stress Mitigation Using Consortia.

Bacterial endophytes (120) were isolated from six halophytes (Distichlis spicata, Cynodon dactylon, Eragrostis obtusiflora, Suaeda torreyana, Kochia scoparia, and Baccharis salicifolia). These halophiles were molecularly identified and characterized with or without NaCl conditions. Characterization was based on tests such as indole acetic acid (IAA), exopolysaccharides (EPS), and siderophores (SID) production; solubilization of phosphate (P), potassium (K), zinc (Zn), and manganese (Mn); mineralization of phytate; enzymatic activity (acid and alkaline phosphatase, phytases, xylanases, and chitinases) and the mineralization/solubilization mechanisms involved (organic acids and sugars). Moreover, compatibility among bacteria was assessed. Eleven halophiles were characterized as highly tolerant to NaCl (2.5 M). The bacteria isolated were all different from each other. Two belonged to Bacillus velezensis and one to B. pumilus while the rest of bacteria were identified up to the genus level as belonging to Bacillus, Halobacillus, Halomonas, Pseudomonas, Nesterenkonia, and three strains of Oceanobacillus. The biochemical responses of nutrient solubilization and enzymatic activity were different between bacteria and were influenced by the presence of NaCl. Organic acids were involved in P mineralization and nutrient solubilization. Tartaric acid was common in the solubilization of P, Zn, and K. Maleic and vanillic acid were only detected in Zn and K solubilization, respectively. Furthermore, sugars appeared to be involved in the solubilization of nutrients; fructose was detected in the solubilization tests. Therefore, these biochemical bacterial characteristics should be corroborated in vivo and tested as a consortium to mitigate saline stress in glycophytes under a global climate change scheme that threatens to exacerbate soil salinity.

The effect of modified Qiyuan paste on mice with low immunity and sleep deprivation by regulating GABA nerve and immune system

BackgroundLow immunity and sleep disorders are prevalent suboptimal health conditions in contemporary populations, which render them susceptible to the infiltration of pathogenic factors. LJC, which has a long history in traditional Chinese medicine for nourishing the Yin and blood and calming the mind, is obtained by modifying Qiyuan paste. Dendrobium officinale Kimura et Migo has been shown to improve the immune function in sleep-deprived mice. In this study, based on the traditional Chinese medicine theory, LJC was prepared by adding D. officinale Kimura et Migo to Qiyuan paste decoction.MethodsIndicators of Yin deficiency syndrome, such as back temperature and grip strength, were measured in each group of mice; furthermore, behavioral tests and pentobarbital sodium-induced sleep tests were performed. An automatic biochemical analyzer, enzyme-linked immunosorbent assay kit, and other methods were used to determine routine blood parameters, serum immunoglobulin (IgG, IgA, and IgM), cont (C3, C4), acid phosphatase (ACP) and lactate dehydrogenase (LDH) levels in the spleen, serum hemolysin, and delayed-type hypersensitivity (DTH) levels. In addition, serum levels of γ-aminobutyric acid (GABA) and glutamate (Glu) were detected using high-performance liquid chromatography (HPLC). Hematoxylin–eosin staining and Nissl staining were used to assess the histological alterations in the hypothalamus tissue. Western blot and immunohistochemistry were used to detect the expressions of the GABA pathway proteins GABRA1, GAD, GAT1, and GABAT1 and those of CD4+ and CD8+ proteins in the thymus and spleen tissues.ResultsThe findings indicated that LJC prolonged the sleep duration, improved the pathological changes in the hippocampus, effectively upregulated the GABA content in the serum of mice, downregulated the Glu content and Glu/GABA ratio, enhanced the expressions of GABRA1, GAT1, and GAD, and decreased the expression of GABAT1 to assuage sleep disorders. Importantly, LJC alleviated the damage to the thymus and spleen tissues in the model mice and enhanced the activities of ACP and LDH in the spleen of the immunocompromised mice. Moreover, serum hemolysin levels and serum IgG, IgA, and IgM levels increased after LJC administration, which manifested as increased CD4+ content, decreased CD8+ content, and enhanced DTH response. In addition, LJC significantly increased the levels of complement C3 and C4, increased the number of white blood cells and lymphocytes, and decreased the percentage of neutrophils in the blood.ConclusionsLJC can lead to improvements in immunocompromised mice models with insufficient sleep. The underlying mechanism may involve regulation of the GABA/Glu content and the expression levels of GABA metabolism pathway-related proteins in the brain of mice, enhancing their specific and nonspecific immune functions.Graphical

The effect of Astragalus polysaccharides on the repair of adverse effects in largemouth bass (Micropterus salmoides) under enrofloxacin stress

Antibiotics have important role in controlling the outbreak of bacterial diseases in fish farming, but long-term use or persistent existence of antibiotics in water can cause adverse effects on aquatic animals. In order to evaluate repairing effect of Astragalus polysaccharides (APS) on damaged intestine of fish under enrofloxacin (ENR) stress, ENR-pretreated (1.0 mg/L, 7 days) largemouth bass were randomly divided into two groups, and subsequently were fed basal diet and diet supplemented with 1.0 g/kg APS for 14 days. Intestine tissue and content were sampled on day 0 (D0), days 7 (D7), days 21 (D21_APS and D21) to detect the intestinal structure, intestinal microbiota structure, oxidative stress, non-specific immune and inflammatory response.Intestinal tissue section showed that the height, width of intestinal villi, and muscular thickness in D21_APS were significantly greater than those on D0, D7, and D21 (P < 0.05). APS-supplemented diet was significantly increased expression of tight junction protein related genes occludin, claudin-1, ZO-1 (P < 0.05). APS addition significantly improved the activities of catalase (CAT) and peroxidase (POD) and decreased superoxide dismutase (SOD) activity (P < 0.05). The activity of CAT and SOD in D21_APS and D0 were similar. The highest activities of acid phosphatase (ACP), lysozyme (LZM) and alkaline phosphatase (AKP) were found in D21_APS group. The expression of proinflammatory factors IL-1β and TNF-α in D21_APS and D21 were significantly down-regulated compared to that of D7, while anti-inflammatory factor IL-10 was up-regulated (P < 0.05). Compared with D7 group, quinolone resistance gene (qnrB) in D21 and D21_APS groups were significantly down-regulated, and in contrast to D21 group, qnrB and qnrS genes in D21_APS group were significantly down-regulated (P < 0.05).High-throughput 16SrRNA gene sequencing revealed proportion of Cyanobacteria in intestinal microbiota increased from 8.23% to 52.66%, while Firmicutes decreased from 28.54% to 2.03% after ENR treatment. In D21 group, Proteobacteria was notable decrease compared to D0, while Firmicutes increased. In D21_APS, the dominant bacteria were Proteobacteria, Fusobacteriota and Firmicutes, and Acinetobacter, Cetobacterium and Aeromonas were the predominant genera. Cluster analysis indicated that bacterial community structure in D21_APS has a similar level to D0 at phylum level. Feeding APS increased abundance of genes related to styrene, isoleucine and lysine degradation; propanoate, butanoate phenylalanine, and tryptophan metabolism; lipopolysaccharide biosynthesis; bacterial secretion system; cell motility and secretion at KEGG pathway Level 3 compared to the basal diet. Taken together, APS can repair the damage of intestinal structure and intestinal microbiota caused by ENR.

Effects of Four Amendments on Cadmium Bioavailability and Enzyme Activity in Purple Soil

In this study, the effects of four types of amendments on effective Cd and Cd content in different parts of prickly ash soil and soil enzyme activity were studied, which provided scientific basis for acidification improvement of purple soil and heavy metal pollution control. A field experiment was conducted. Six treatments were set up:no fertilizer (CK), only chemical fertilizer (F), lime + chemical fertilizer (SF), organic fertilizer + chemical fertilizer (OM), biochar + chemical fertilizer (BF), and vinasse biomass ash + chemical fertilizer (JZ). Soil pH; available Cd (DTPA-Cd); Cd content in branches, leaves, shells, and seeds of Zanthoxylum; as well as the activities of catalase (S-CAT), acid phosphatase (S-ACP), and urease (S-UE) in different treatments were studied, and their relationships were clarified. The results showed following:① The two treatments of vinasse biomass ash + chemical fertilizer and lime + chemical fertilizer significantly increased soil pH (P &lt; 0.05) to 3.39 and 2.25 units higher than that in the control, respectively. Compared with that in the control treatment, the content of available Cd in soil under vinasse biomass ash + chemical fertilizer and lime + chemical fertilizer treatment decreased by 28.91 % and 20.90 %, respectively. ② The contents of Cd in leaves, shells, and seeds of Zanthoxylum were decreased by 31.33 %, 30.24 %, and 34.01 %, respectively. The Cd enrichment ability of different parts of Zanthoxylum was different, with the specific performances being leaves &gt; branches &gt; seeds &gt; shells. Compared with that of the control, the enrichment coefficient of each part of Zanthoxylum treated with vinasse biomass ash + chemical fertilizer decreased significantly(P &lt; 0.05)by 27.54 %-40.0 %. ③ The changes in catalase and urease activities in soil treated with amendments were similar. Compared with those in the control group, the above two enzyme activities were significantly increased by 191.26 % and 199.50 %, respectively, whereas the acid phosphatase activities were decreased by 16.45 %. Correlation analysis showed that soil available Cd content was significantly negatively correlated with soil pH value(P &lt; 0.01), S-CAT and S-UE enzyme activities were significantly positively correlated with soil pH(P &lt; 0.01), and the soil available Cd content was significantly negatively correlated (P &lt; 0.01); the S-ACP enzyme showed the complete opposite trends. The application of lime and vinasse biomass ash to acidic purple soil had the most significant effect on neutralizing soil acidity. It was an effective measure to improve acidic purple soil and prevent heavy metal pollution by reducing the effective Cd content in soil and improving the soil environment while inhibiting the absorption and transfer of Cd in various parts of Zanthoxylum.

Labile carbon content and nutrient availability determines microbial composition in topsoil and subsoil following land‐use change in subtropical China

AbstractEvaluating the impact of land‐use intensification on soil microbial communities is essential for recognizing the implications on microbiome stability and ecosystem function. The microbial biomass and enzyme activity in the topsoil have been found to decrease as a consequence of natural forest conversion; however, the impact of land‐use conversion on the microbes in subsoil remains largely unclear. Here, we examined the effect of primary forest conversion to plantations and cultivated lands on microbial communities at three sites with similar soil, climate, and landform. The forest conversion was set as the experimental treatment, and the primary forest as the control. A linear mixed‐effect model was applied to investigate the role of environmental parameters in shaping the soil microbial biomass and community determined by the phospholipid fatty acids analysis in both the topsoil (0–20 cm) and subsoil (20–40 cm). Compared to the primary forest, the total microbial biomass, β‐1,4‐N‐acetylglucosaminidase, leucine aminopeptidase, acid phosphatase activities, and labile organic C fraction contents in both topsoil and subsoil were reduced in cultivated lands. The ratios of gram‐positive bacteria to gram‐negative bacteria and arbuscular mycorrhizal fungi to saprotrophic fungi in subsoil decreased by 45%–53% and increased by 29%–151%, respectively, following the primary forest conversion to cultivated lands. The response ratio (the percentage of microbial and enzyme indicator response to the primary forest conversion) ranged from −80% to 140% depending on the soil depth, specific microbial group, and converted land‐use type. Microbial biomass and enzyme activity are primarily controlled by the labile organic C content and nutrients availability in both topsoil and subsoil. This study suggests that the primary forest conversion exerts an adverse effect on the microbial biomass, enzyme activity, and substrate availability in both topsoil and subsoil, highlighting the degradation of subsoil health in subtropical China.

English

An incubation study investigated the decomposition patterns, microbial activities, soil aggregates distribution, and soil organic carbon (SOC) contents, using four crop residues; wheat (Triticum aestivum L.), rice (Oryza sativa L.), cotton (Gossypium hirsutum L.), and maize (Zea mays L.), at low and high rates (10 and 20 g kg–1). An average increase of about 35% in cumulative C-CO2 emissions and 26% in soil microbial biomass carbon (MBC) was observed at high residue rates as compared to low rates. A positive and strong correlation (0.96) was found between C-CO2 emissions and MBC, and the effect of residue quality on decomposition was found to be less at high rates. The relative reduction in C-CO2 emissions by adding rice residues may be due to their high silica content. Differences in extracellular enzyme activities (EEA) with different residues indicated the effect of residue quality on microbial activities. Cotton residues increased β-glucosidase and chitinase activities by 41 and 38%, respectively, at high rates than at low rates. High maize residues also markedly increased chitinase activity by 41%, implying higher N cycling and fungal prevalence. Acid phosphatase activity was found to increase by about 25 to 32% with high rice and wheat residues, respectively. Higher EEA at high residues input likely reflected the microbial nutritional limitations. Crop residues raised SOC content from 0.7 under control to 1.0% at low residues input but not at high input. Increased macro-aggregates fraction at high residues input may be attributed to higher microbial activities. In summary, high residues input can minimize residue biochemical quality’s effect on decomposition, with no further increase in SOC content. While a positive effect on the soil MBC, but not on the SOC content, was observed at high residue input, suggesting moderation in the additions of organic amendments is key for SOC buildup. Crop residues, added at 10 g kg–1, may help maintain a positive SOC balance in the arid agroecosystems by moderating higher microbial activities and soil respiration.

Astragalus membranaceus (Fisch.) Bge. administered by dissolving microneedles achieves systemic therapeutic effects at low doses

ObjectiveTo determine the main components of Astragalus membranaceus (Fisch.) Bge (A. membranaceus, Huang Qi), Astragaloside IV (AIV) and Astragalus polysaccharides (AP), to characterize their properties, evaluate their in vivo efficacy, and to analyze drug diffusion using dissolving microneedle (DMN) technology in vivo. MethodsRespectively, AIV- and AP-loaded DMNs comprising chitosan (CTS) and polyvinyl alcohol (PVA) were prepared via dual-mold forming. Their morphology, mechanical properties, in vivo solubility, and skin irritation characteristics were tested. In vivo efficacy was assessed in cyclophosphamide-induced immunosuppressed mice, in vivo diffusion of AIV and AP by DMNs and conventional methods was compared, and the rheological properties of AIV-CTS-PVA and AP-CTS-PVA mixtures were measured. ResultsSubcutaneous dissolution and absorption of AIV-CTS-PVA and AP-CTS-PVA microneedles (MNs) at low doses (50%–17% of intraperitoneal AIV injection and 12%–4% of intravenous AP injection) reduced the spleen index and acid phosphatase activity in immunosuppressed mouse models, increased the thymus index, and achieved equivalent or better systemic therapeutic effects. Compared with injections, AIV and AP achieved controllable solid-liquid conversion through delivery with CTS-PVA MNs, resulting in highly localized aggregation within 48 h, reducing the initial explosive effect of the drug, and achieving stable and slow drug release. ConclusionThe present study enhances our understanding of the efficacy and remote effects of drug-loaded DMNs from a traditional Chinese medicine (TCM) perspective, thereby promoting the development of precise and efficient delivery of TCM and further expanding the drug-loading range and application scenarios for DMNs.

Metabolic Profile in Rats during Long-Term Restriction of Motor Activity.

We performed a comprehensive study of protein (total protein, medium-molecular-weight peptides, creatinine, and urea), purine (uric acid), and lipid (cholesterol, triglycerides) metabolism, activity of AST, ALT, and acid phosphatase in blood plasma of white male rats under conditions of restriction of motor activity up to 28 days. Patterns of changes in metabolic profile during hypokinesia were established: prevalence of catabolic processes and atherogenic shifts in the lipid spectrum with maximum manifestation on 14-21 days of the experiment.

Novel artificial tricalcium phosphate and magnesium composite graft facilitates angiogenesis in bone healing

BackgroundBone grafting is the standard treatment for critical bone defects, but autologous grafts have limitations like donor site morbidity and limited availability, while commercial artificial grafts may have poor integration with surrounding bone tissue, leading to delayed healing. Magnesium deficiency negatively impacts angiogenesis and bone repair. Therefore, incorporating magnesium into a synthetic biomaterial could provide an excellent bone substitute. This study aims to evaluate the morphological, mechanical, and biological properties of a calcium phosphate cement (CPC) sponge composed of tetracalcium phosphate (TTCP) and monocalcium phosphate monohydrate (MCPM), which could serve as an excellent bone substitute by incorporating magnesium. MethodsThis study aims to develop biomedical materials composed mainly of TTCP and MCPM powder, magnesium powder, and collagen. The materials were prepared using a wet-stirred mill and freeze-dryer methods. The particle size, composition, and microstructure of the materials were investigated. Finally, the biological properties of these materials, including 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay for biocompatibility, effects on bone cell differentiation by alkaline phosphatase (ALP) activity assay and tartrate-resistant acid phosphatase (TRAP) activity assay, and endothelial cell tube formation assay for angiogenesis, were evaluated as well. ResultsThe data showed that the sub-micron CPC powder, composed of TTCP/MCPM in a 3.5:1 ratio, had a setting time shorter than 15 minutes and a compressive strength of 4.39±0.96 MPa. This reveals that the sub-micron CPC powder had an adequate setting time and mechanical strength. We found that the sub-micron CPC sponge containing magnesium had better biocompatibility, including increased proliferation and osteogenic induction effects without cytotoxicity. The CPC sponge containing magnesium also promoted angiogenesis. ConclusionIn summary, we introduced a novel CPC sponge, which had a similar property to human bone promoted the biological functions of bone cells, and could serve as a promising material used in bone regeneration for critical bone defects.

Acidovorax bellezanensis sp. nov., a novel bacterium from uranium mill tailings repository sites with selenium bioremediation capabilities

A Gram-stain-negative bacterial strain designated Be4T, belonging to the genus Acidovorax, was isolated from mining porewaters sampled in uranium mill tailings repository sites, located in Bellezane, near Bessines-sur-Gartempe (Limousin, France). Cells were facultative anaerobic, rod-shaped, non-endospore-forming and motile with flagella. The mean cell size was 1.25–1.31 μm long and 0.70–0.73 μm wide. Colonies were light yellow, opaque, circular, convex with smooth margins, and 1–2 mm in diameter. Growth occurs at 4–37 °C and between pH 5.5–9.0. It differed from its phylogenetically related strains by phenotypic and physiological characteristics such as growth at 4 °C, presence of acid phosphatase, naphthol-AS-BI-phosphohydrolase and β-glucosidase enzymatic activities, and fermentation of l-xylose and esculin. The major fatty acids were C16:0, C16:1 ω7c/C16:1 ω6c, C17:0 cyclo and C18:1 ω7c. Phylogenetic analysis based on 16S rRNA and 938 core genes, confirmed its placement within the genus Acidovorax as a novel species. Strain Be4T showed highest 16S rRNA sequence similarity to Acidovorax antarcticus (98.2 %), Acidovorax radicis (97.9 %), Acidovorax temperans (97.8 %) and Acidovorax facilis (97.7 %). The genome of strain Be4T is 5,041,667 bp size with a DNA G + C content of 65.15 %. By automatic annotation numerous sequences involved in the interaction with metals/metalloids including some genes related to Se uptake and selenite resistance were detected in its genome. The average nucleotide identity (ANI) values calculated from whole genome sequences between strain Be4T and the most closely related strains A. radicis and A. facilis were below the threshold value of 95 %. Thus, the data from the phylogenetic, physiological, biochemical, and genomic analyses clearly indicates that strain Be4T represents a novel species with the suggested name Acidovorax bellezanensis sp. nov. The type strain is Acidovorax bellezanensis Be4T (=DSM116209T = CECT30865T). This novel species, due to its unique isolation source, genomic analysis, and preliminary laboratory tests where it was able to reduce toxic Se(IV) to less harmful Se(0) in the form of nanoparticles, holds great potential for further investigation in bioremediation, particularly concerning Se.

Maize/Soybean Intercropping with Straw Return Increases Crop Yield by Influencing the Biological Characteristics of Soil.

With mounting demand for high-quality agricultural products and the relentless exploitation of arable land resources, finding sustainable ways to safely cultivate food crops is becoming ever more important. Here, we investigated the effects of the integrated cropping technique "straw return + intercropping" on the soil aggregates as well as the microbial biomass carbon (MBC) content, enzyme activities and microbial diversity in soils of maize and soybean crops. Our results show that in comparison to straw removal and monoculture, straw return and intercropping increase the rhizosphere's MBC content (59.10%) of soil, along with urease (47.82%), sucrase (57.14%), catalase (16.14%) and acid phosphatase (40.66%) activities as well as the microbial diversity under maize and soybean. Under the same straw treatment, the yield of maize when intercropped surpassed that when grown in monoculture, with the land equivalent ratio of the intercropping treatment under straw return being highest. Overall, the intercropping of maize and soybean is beneficial for the healthy development of sustainable agriculture in the black soil region of northeast China, especially when combined with straw return to fields.

Isolation of the inorganic phosphorus-solubilizing bacteria Lysinibacillus sphaericus and assessing its role in promoting rice growth.

Soluble phosphorus scarcity severely limits plant growth and crop yield. In this study, a strain of inorganic phosphorus-solubilizing bacteria, Lysinibacillus sphaericus, was isolated from rice rhizosphere soil. The available phosphorus content in liquid inorganic phosphorus identification medium and in L. sphaericus-inoculated soil increased from 204.28mg/L to 1124.68mg/L and from 4.75mg/kg to 7.04mg/kg, respectively. The pH decreased significantly from 6.87 to 6.14. Incubation with L. sphaericus significantly increased malic and succinic acid content in the liquid inorganic phosphorus identification medium and increased acid phosphatase and alkaline phosphatase activity in the soil. Inoculation with L. sphaericus significantly increased rice growth, chlorophyll a/b content, and photosynthesis by increasing the soluble phosphorus content in the rice rhizosphere soil under phosphorus-deficient conditions. Further analysis revealed that L. sphaericus improved soil phosphorus release by decreasing soil pH and promoting acid phosphatase and alkaline phosphatase activity. This study supports the production of microbial fertilizers to improve rice yield in phosphorus-deficient conditions.

Impacts of MnO2 on tomato (Lycopersicon esculentum Mill.) growth: A study with MnO2-amended organic fertilizer

Manganese dioxide (MnO2), as a catalyst in composting processes, can accumulate in soil over multiple fertilizations. However, its impact on crop growth remains to be explored. In this study, a pot experiment was conducted to investigate the impacts of MnO2 on the tomato plant performance across various growth stages. Results showed that MnO2 reduced the plant height, leaf number and length by 35.53 %, 27.61 %, and 37.00 %, respectively, and decreased the fruit weight (23.16 %) and sugar-acid ratio (29.7 %) of fruits compared to the MnO2-free control. The adverse impacts of MnO2 on plant growth might be attributed to the inhibition of microbial activity in soil reflected by the reduction of soil urease (9.30 %) and acid phosphatase (12.52 %) activities, which decreased the efficiency of nutrients conversion and uptake. The decrease of nutrient elements in roots resulted in oxidative stress in the plant, inhibiting the plasma membrane H+-ATPase activity thereby reducing the translocation of nutrients (e.g., calcium, magnesium, and phosphorus) translocation from roots to leaves. Furthermore, the phytohormones indolebutyric acid, gibberellin, and jasmonic acid of leaves were disturbed. This study reveals the risks associated with the application of MnO2-containing organic fertilizers.

The Potential Impact of Long-Term Copper Fungicide Sprays on Soil Health in Avocado Orchards

The long-term use of copper (Cu)-based fungicide sprays in orchards is associated with changes in soil Cu levels. However, there is a gap in knowledge regarding the potential accumulation of Cu in orchards and the associated impacts on the soil microbial structure. This study assessed the possibility of Cu accumulation in different avocado orchard farms and further evaluated the potential effect on soil microbial activities. Soil Cu levels were quantified in Tauranga and Northland, and three avocado orchards were analysed in each experimental location. All avocado farms in both sites received Cu-based fungicide sprays for over eight years. Soil samples were collected at a 0–20 cm depth from all six orchards. The soil total and bioavailable Cu, changes in soil chemical properties, microbial biomass, dehydrogenase activity, alkaline phosphatase activity, and acid phosphatase activity were measured. The results revealed that the total Cu and bioavailable Cu concentrations in Tauranga orchards were 81.3 and 0.32, 196.7 and 0.82, and 33.6 and 0.31 mg Cu kg−1 in Farms 1, 2, and 3, respectively. In Northland orchards, the total Cu and bioavailable Cu were 54.5 and 0.06, 18.4 and 0.77, and 46 and 0.34 mg Cu kg−1 in Farm 1, 2, and 3, respectively. Five out of six of the avocado orchard farms assessed in this study had total Cu concentrations greater than 30 mg Cu kg−1 reported in New Zealand native land. The magnitude of Cu accumulation was linked with soil pH and C content. No clear trend was observed between soil Cu concentrations and the soil microbial activity. Our study results demonstrated that the long-term use of Cu-based fungicide sprays can elevate Cu concentrations in orchard soils. Mitigation strategies need to be explored to abate the accumulation of Cu in orchard soils.

Root systems of peanut cultivars respond differently to soil P availability to improve P uptake

AbstractBackgroundPeanut (Arachis hypogaea L.) is regarded as a crop with high nutrient use efficiency, but there may be differences between cultivars. Furthermore, there is little information on the strategy of peanut cultivars to adapt to soil P availability and to what extent they explore non‐labile P pools.AimsOur objective was to evaluate growth, root morphology, enzymatic activity in the rhizosphere, and P uptake of peanut cultivars grown under different soil P status.MethodsThe study was conducted in a greenhouse in 6‐L pots. Soils with low P (without fertilization) and high P content (with fertilization) and seven peanut cultivars of different origins, different maturation groups, and release years were investigated. Peanut shoot yield, phosphorus uptake, root growth, soil P fractions as well as phosphatase activity in the rhizosphere soil were determined.ResultsIn P‐deficient soil, a higher dry matter yield was associated with longer root hairs and root length, which resulted in decreased soil non‐labile P was observed mainly with cultivars developed in Argentina (ARG‐medium‐old and ARG‐medium‐new) and the late maturity Brazilian cultivar (BR I‐late new). These cultivars adapted well to P deficiency and were less dependent on labile P. New Brazilian early and medium maturity cultivars developed less, shorter root hairs, and showed low acid phosphatase activity in the rhizosphere under P deficiency, resulting in lower P uptake and dry matter yield. Under high P availability, new Brazilian cultivars of medium and late maturity showed the highest dry matter yield (9.0 and 9.8 g plant−1, respectively) and longest roots, around 120 m plant−1. High P availability decreased root hairs in all cultivars.ConclusionOverall, the adaptation of peanut cultivars to P‐deficient soils was lower for the new mid‐ and early‐maturing Brazilian cultivars compared with the Argentinian and old or late‐maturing Brazilian cultivars. The main strategies of P‐efficient cultivars under low P availability are to increase root length, root hair length, and root hair density.

Maize/soybean intercropping increases nutrient uptake, crop yield and modifies soil physio-chemical characteristics and enzymatic activities in the subtropical humid region based in Southwest China

Intercropping, a widely adopted agricultural practice worldwide, aims to increase crop yield, enhance plant nutrient uptake, and optimize the utilization of natural resources, contributing to sustainable farming practices on a global scale. However, the underlying changes in soil physio-chemical characteristics and enzymatic activities, which contribute to crop yield and nutrient uptake in the intercropping systems are largely unknown. Consequently, a two-year (2021–2022) field experiment was conducted on the maize/soybean intercropping practices with/without nitrogen (N) fertilization (i.e., N0; 0 N kg ha−1 and N1; 225 N kg ha−1 for maize and 100 N kg ha−1 for soybean ) to know whether such cropping system can improve the nutrients uptake and crop yields, soil physio-chemical characteristics, and soil enzymes, which ultimately results in enhanced crop yield. The results revealed that maize intercropping treatments (i.e., N0MI and N1MI) had higher crop yield, biomass dry matter, and 1000-grain weight of maize than mono-cropping treatments (i.e., N0MM, and N1MM). Nonetheless, these parameters were optimized in N1MI treatments in both years. For instance, N1MI produced the maximum grain yield (10,105 and 11,705 kg ha−1), biomass dry matter (13,893 and 14,093 kg ha−1), and 1000-grain weight (420 and 449 g) of maize in the year 2021 and 2022, respectively. Conversely, soybean intercropping treatments (i.e., N0SI and N1SI) reduced such yield parameters for soybean. Also, the land equivalent ratio (LER) and land equivalent ratio for N fertilization (LERN) values were always greater than 1, showing the intercropping system’s benefits in terms of yield and improved resource usage. Moreover, maize intercropping treatments (i.e., N0MI and N1MI) and soybean intercropping treatments (i.e., N0SI and N1SI) significantly (p < 0.05) enhanced the nutrient uptake (i.e., N, P, K, Ca, Fe, and Zn) of maize and soybean, however, these nutrients uptakes were more prominent in N1MI and N1SI treatments of maize and soybean, respectively in both years (2021 and 2022) compared with their mono-cropping treatments. Similarly, maize-soybean intercropping treatments (i.e., N0MSI and N1MSI) significantly (p < 0.05) improved the soil-based N, P, K, NH4, NO3, and soil organic matter, but, reduced the soil pH. Such maize-soybean intercropping treatments also improved the soil enzymatic activities such as protease (PT), sucrose (SC), acid phosphatase (AP), urease (UE), and catalase (CT) activities. This indicates that maize-soybean intercropping could potentially contribute to higher and better crop yield, enhanced plant nutrient uptake, improved soil nutrient pool, physio-chemical characteristics, and related soil enzymatic activities. Thus, preferring intercropping to mono-cropping could be a preferable choice for ecologically viable agricultural development.

Rhizophagus intraradices and Azospirillum brasilense improve growth of herbaceous plants and soil biological activity in revegetation of a recovering coal-mining area.

We assessed, in a field experiment, the effects of arbuscular mycorrhizal fungi (Rhizophagus intraradices) and plant growth-promoting bacteria (Azospirillum brasilense) on the soil biological activity and the growth of key pioneer species used in the revegetation of coal-mining areas undergoing recovery. We applied four inoculation treatments to the pioneer plant species (Lablab purpureus, Paspalum notatum, Crotalaria juncea, Neonotonia wightii, Stylosanthes guianensis, Andropogon gayanus and Trifolium repens) used in the recovery process: NI (Control - Non-inoculated), AZO (A. brasilense), AMF (R. intraradices), and co-inoculation of AZO and AMF. On the 75th and 180th days, we measured plant dry mass, mycorrhizal colonization, N and P concentration, and accumulation in plant tissue. We collected soil to quantify glomalin content and soil enzyme activity. After 180 days, we did a phytosociological characterization of the remaining spontaneous plants.The both microorganisms, singly or co-inoculated, promoted increases in different fractions of soil glomalin, acid phosphatase activity, and fluorescein diacetate activity at 75 and 180 days. The inoculation was linked to higher plant biomass production (62-89%) and increased plant P and N accumulation by 34-75% and 70-85% at 180 days, compared with the non-inoculated treatment. Among the pioneer species sown Crotalaria juncea produced the highest biomass at the 75th and 180th days (67% and 76% of all biomass), followed by Lablab purpureus (3% and 0.5%), while the other species failed to establish. At 180 days, we observed twenty spontaneous plant species growing in the area, primarily from the Poaceae family (74%). That suggests that the pioneer species present in the area do not hinder the ecological succession process. Inoculation of R. intraradices and A. brasilense, isolated or combined, increases soil biological activity, growth, and nutrient accumulation in key pioneer plant species, indicating the potential of that technique for the recovery of lands degraded by coal mining.

Microbial Biomass and Rhizosphere Soil Properties in Response to Heavy Metal-Contaminated Flooding

Mining and metallurgy are the main sources of soil contamination with harmful metals, posing a significant threat to human health and ecosystems. River floodplains in the vicinity of metal mines or industrial plants are often subject to flooding with sediments containing heavy metals, which can be harmful to the soil ecosystem. This study aimed to investigate the microbial properties of the soil at a metal-contaminated site and to determine the significant relationships between the biological and chemical properties of the soil. The study site was located near the village of Gyöngyösoroszi, in the Mátra mountain region of Northwest Hungary. A phytoremediation experiment was conducted in a metal-polluted floodplain using willow and corn plantations. The soil basal respiration, substrate-induced respiration, soil microbial biomass carbon (MBC), acid phosphatase activities, and soil chemical properties were measured. The soil of the contaminated sites had significantly higher levels of As, Pb, Zn, Cu, Cd, and Ca, whereas the unpolluted sites had significantly higher levels of phosphorus and potassium. The substrate-induced respiration showed a positive correlation with MBC and negative correlations with the metabolic quotient (qCO2). The soil plasticity index and phosphorus showed a positive correlation with MBC, whereas salinity and the presence of Cd, Pb, Zn, As, and Cu showed a negative correlation. Acid phosphomonoesterase activity negatively correlated with the plant-available phosphorus content and MBC, but was positively correlated with the contents of toxic elements, including cadmium, lead, zinc, arsenic, and copper. This study found a significant correlation between the qCO2 and the toxic element content. This suggests that an enhanced metabolic quotient (qCO2), together with a decreased MBC/SOC ratio, could be used to indicate the harmful effect of soil contamination by heavy metals in floodplain soils.

Ascertaining variations in the activity of larval midgut enzymes of Helicoverpa armigera by dietary emamectin benzoate through biochemical and in silico docking study

Helicoverpa armigera, a ubiquitous polyphagous pest, poses a significant threat to global agriculture, causing substantial economic losses and demonstrating resistance to synthetic pesticides. This study investigates the potential of emamectin benzoate (EMB), an avermectin derivative, as an effective control agent against H. armigera. The larvae of the NBII-MP–NOC–01 strain of H. armigera were reared on an artificial diet. The impact of dietary EMB was examined on four midgut enzymes; alanine aminotransferase (ALT), aspartate aminotransferase (AST), acid phosphatase (ACP), and alkaline phosphatase (ALP). Results showed a dose-dependent and time-dependent reduction in ALT and AST activity, while an initial increase and subsequent decline in ACP and ALP activity at higher EMB concentrations. Computational modelling of enzyme structures and molecular docking studies revealed differential binding of EMB with the midgut enzymes. The strongest interaction was observed between EMB and ALT residues, contrasting with weakest interactions observed with AST. The study also showed that decreased activity of transaminases in H. armigera caused by EMB may be because of stability-activity trade-off, while in phosphatases reverse may be the case. This research provides crucial insights into the biochemical responses and the intricate insecticide-enzyme interactions in H. armigera caused by EMB exposure. This study lays the foundation for further research aimed at developing environmentally friendly approaches for managing H. armigera, addressing the challenges associated with conventional pesticides.

Beta-Cyfluthrin-Induced Hepatic Alterations in Zebrafish: Enzymatic Profiles and Oxidative Stress Responses

Beta-Cyfluthrin is a widely used pesticide belonging to class of synthetic pyrethroids which affects the central and peripheral nervous systems. The current study investigates the impact of beta-Cyfluthrin on the biochemical parameters of liver of zebrafish (Danio sp.). Adult zebrafish were exposed to concentrations of 0.25, 0.5, 1.0, 2.0 and 4.0 µg/L of beta-Cyfluthrin for acute (96 hours) and chronic (21 days) exposure periods respectively (n=20). It was observed that exposure to beta-Cyfluthrin led to variations in biochemical markers in both acute and chronic exposure groups. Liver function tests revealed significant elevated activity of alanine transaminase (ALT) and aspartate transaminase (AST) at exposure concentrations of 2.0 and 4.0 µg/L of beta-Cyfluthrin in both acute and chronic groups, while acid phosphatase (ACP) and alkaline phosphatase (ALP) activity decreased significantly at concentrations of 1.0, 2.0 and 4.0 µg/L in the chronic group. Lipid peroxidation exhibited a concentration and time-dependent increase with significant difference at 1.0, 2.0 and 4.0 µg/L in both acute and chronic groups, while superoxide dismutase (SOD) and peroxidase (PER) levels declined significantly in both acute and chronic exposure groups at exposure concentrations of 1.0, 2.0 and 4.0 µg/L for SOD and 2.0 and 4.0 µg/L for PER. Catalase (CAT) initially increased significantly in acute groups of 1.0, 2.0 and 4.0 µg/L but decreased in chronic ones. Glutathione S-transferase (GST) levels exhibited a significant increase at lower concentrations of 0.25 µg/L but a decrease at higher concentrations, 1.0, 2.0 and 4.0 µg/L of beta-Cyfluthrin. The level of significance were considered at p&lt;0.05 and p&lt;0.01. This research suggests that exposure to beta-Cyfluthrin leads to hepatic damage in adult zebrafish. This indicates a potential risk to non-target aquatic fauna, through runoff where beta-Cyfluthrin is used as an agricultural pesticide.