Nanobubble-mediated high-density growth and enzyme activity enhancement of petroleum degrading bacterium Rhodococcus erythropolis KB1: Mechanism and application.

Struvite produced from human urine is rich in macronutrients. It can be used as a slow-release fertilizer, which helps to promote growth and increase the productivity of agricultural crops. However, struvite may contain pharmaceuticals that can alter the quality of agricultural soils. Here, a greenhouse study was conducted to investigate the effects of struvite and pharmaceutical-contaminated struvite on biological indicators of soil quality (microbial growth, microbial biomass, basal respiration, metabolic quotient, and enzyme activity). The struvite was separately contaminated with a mixture of four antibiotics and four neuroactive at three different concentrations, 1, 10, and 100 mg kg −1 . The results showed that more than 90% of the pharmaceuticals were not present in the soil after the first 7 days of the study. The effects varied depending on the type of indicator, the pharmaceutical, the concentration, and the day analyzed. Soils that received contaminated struvite generally had lower growth of total heterotrophic bacteria (BHtot) and nitrogen-fixing bacteria (FixN), microbial biomass (MBC), and activity of fluorescein diacetate hydrolases (FDA-H) and dehydrogenases (DHA), but higher basal respiration (SBR) and metabolic quotient (qCO 2 ) in the first 7 days. These results indicate that soil microorganisms exposed to contaminated struvite were under stress during the initial phase struvite application. However, these microorganisms showed the ability to recover by increasing microbial growth by 0.1–1.8 log 10 CFU, microbial biomass by 5.3%–102%, and enzymatic activity by 76%–774%. Both positive and negative effects were observed mainly for struvite contaminated with antibiotics. The results obtained help to clarify concerns about the safety of struvite produced from human urine. The ability of soil microorganisms to recover after stress is important to support the responsible use of this fertilizer and encourage more sustainable agricultural practices. However, the effects of pharmaceutical-contaminated struvite resulting from continuous application during successive crops should be considered in future studies.

Abstract Purpose In recent years, intercropping in olive groves has become a sustainable practice for mitigating climate change. Therefore, the objective of this study was to determine whether crop diversification in rainfed olive groves modifies carbon dioxide (CO 2 ), nitrous oxide (N 2 O), and methane (CH 4 ) emissions and key chemical and enzymatic properties of the soil in the short term. Materials and methods A field experiment was conducted under semi-arid Mediterranean conditions using four treatments: a conventional olive monocrop (CP) and three crop diversification systems: saffron ( Crocus sativus ) (D-S), oats and vetch ( Vicia sativa and Avena sativa ) (D-O) and lavandin ( Lavandula × intermedia ) (D-L). CO 2 , N 2 O, and CH 4 emissions were measured periodically using closed static chamber techniques. Simultaneously, soil samples were analyzed to determine physicochemical parameters (pH, total nitrogen (TN), total organic carbon (TOC), P available, K, and Fe) and enzymatic activities (β-1,4-glucosidase (BG), leucine aminopeptidase (LA), N-acetylglucosaminidase (NAG), Arylsulfatase (AS) and phosphatase (AP) and dehydrogenase (DH)) in order to evaluate the interactions between soil properties and gas fluxes. Results and discussion The results showed that CO 2 emissions were significantly higher in D-S (385.2 mg CO 2 m -2 h -1 ) and D-O (335.2 mg CO 2 m -2 h -1 ) compared to CP, which was attributed to increased microbial and root activity promoted by the vegetation cover. In contrast, N 2 O fluxes (0.002 mg N 2 O m -2 h -1 in CP, 0.007 in D-S, 0.001 in D-O, and − 0.002 in D-L) and CH 4 (–0.2 mg CH 4 m -2 h -1 in CP, 0.1 in D-S, 0.2 in D-O, and 0.2 in D-L) did not show significant differences between all treatments ( p > 0.05 ), probably due to the prevailing semi-arid conditions. D-O had higher values of P available, Fe, and TN, while D-S and D-L stood out for higher values of K and TOC, both compared to CP. Enzymatic activities were particularly higher in D-S and D-O, specifically BG, LA, and AS. In addition, positive and significant correlations were observed between CO₂ accumulation and several soil parameters: in D-S, with POC, total Zn, exchangeable Na, total Cu, and BG, LA, and AS activities; and in D-L, with POC, exchangeable Na, total Mn, P available, TN, and LA and AS activities, highlighting that these indicators contribute to the regulation of greenhouse gas (GHG) emissions. Conclusion It was concluded that crop diversification in rainfed olive groves increases CO 2 emissions in the short term due to intensified biological activity, but at the same time improves soil fertility and biochemical functionality. However, long-term monitoring is required to determine whether these systems contribute to carbon stabilization and net sequestration, ensuring their potential as sustainable strategies for climate change mitigation in Mediterranean agroecosystems.

The interaction between organic and inorganic nutrients, bacterial communities, and soil fertility has been well documented over time. Conventional agricultural systems heavily utilize both inorganic and organic fertilizers, each exerting distinct effects on soil microbial dynamics and plant growth. The objective of our experiments was to identify the most effective fertilization strategy for improving the biological quality of a microbiologically impoverished and low-productivity soil. To this end, four fertilization strategies were evaluated: (i) organic fertilizers characterized by a high content of organic carbon (Fertil 4-5-7-variant 1); (ii) organic fertilizers with 12% organic nitrogen from proteins (Bio Ostara N-variant 2) (iii) combined inorganic-organic fertilizers (P35 Bio-variant 3) and (iv) mineral (inorganic) fertilizers (BioAktiv-variant V4). This study aimed to assess the short-term effects of fertilizers with varying chemical compositions on the density of cultivable heterotrophic bacteria and their associated dehydrogenase (DH) activity in a petrocalcic chernozem soil containing pedogenic carbonates. Soil sampling was conducted according to a randomized block design, comprising four replicates per treatment (control plus four fertilizer types). The enumeration of cultivable bacteria was performed using Nutrient Agar and A2R Agar media, whereas dehydrogenase activity (DHA) was quantified based on the reduction of 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) to 1,3,5-triphenyl-tetrazolium formazan (TPF) by bacterial dehydrogenase enzymes. Marked differences were observed in both parameters between the plots amended with inorganic fertilizers and those treated with organic fertilizers, as well as among the organic fertilizer treatments of varying composition. The most pronounced increases in both bacterial density and dehydrogenase activity (DHA) were recorded in the plots receiving the fertilizer with a high organic nitrogen content. In this treatment, the maximum bacterial population density reached 6.25 log10 CFU g-1 dry soil after approximately two months (May), followed by a significant decline starting in July. In contrast, DHA exhibited a more rapid response, reaching its peak in April (42.75 µg TPF g-1 soil), indicating an earlier DHA activation of microbial metabolism. This temporal lag between the two parameters suggests that enzymatic activity responded more swiftly to the nutrient inputs than did microbial biomass proliferation. For the other two organic fertilizer variants, bacterial population dynamics were broadly similar, with peak densities recorded in June, ranging from 5.98 log10 CFU g-1 soil (V3) to 6.03 log10 CFU g-1 soil (V1). A comparable trend was observed in DHA: in V3, maximum DHA was attained in June (30 µg TPF g-1 soil), after which it remained relatively stable, whereas in V1, it peaked in June (24.05 µg TPF g-1 soil) and subsequently declined slightly toward the end of the experimental period. Overall, the temporal dynamics of bacterial density and DHA demonstrated a strong dependence on the quality and biodegradability of the organic matter supplied by each fertilizer. Both parameters were consistently lower under inorganic fertilization compared with organic treatments, suggesting that the observed increases in microbial density and activity were primarily mediated by the enhanced availability of organic substrates. The relationship between the density of culturable heterotrophic bacteria and dehydrogenase (DH) activity was strongly positive (r = 0.79), indicating a close functional linkage between bacterial density and oxidative enzyme activity. This connection suggests that the culturable fraction of the heterotrophic microbial community plays a key role in the early stages of organic matter mineralization derived from the applied fertilizers, particularly in the decomposition of easily degradable substrates.

Background: A recent study of our group quantifying 13C-octanoate metabolism in HA (Capanna Margherita [MG]/4,559 m) showed that acute HA exposure might lead to an increase of the lipolytic and CO2-producing pathways. Objective: To further test this hypothesis, we investigated intestinal biopsies from the same participants from simultaneously performed endoscopy studies for changes of mRNA-expression levels of the beta-oxidation enzymes and the decarboxylating tricarboxylic acid cycle (TCA) enzymes. Methods: Duodenal biopsies of 16 subjects exposed to HA were sampled via gastro-duodenoscopy at Zurich (baseline ZH, 490 m), on day 2 (MG2) and on day 4 at HA (MG4). After mRNA extraction, quantitative real-time polymerase chain reaction was performed to assess mRNAs expression of TCA cycle enzymes as well as beta-oxidation enzymes. Results: Aconitase mRNA levels increased early (MG2 vs. ZH, p < 0.05) and were still higher at day 4 compared with ZH (MG4 vs. ZH, p < 0.05). Isocitrate dehydrogenase (DH) levels increased with time spent at 4,559 m (MG4 vs. ZH, p < 0.01). The remaining TCA cycle and beta-oxidation enzymes investigated tended to higher values at HA but without reaching significance. Conclusion: We conclude that acute exposure to HA leads to increased transcription of aconitase and isocitrate DH in the duodenal mucosa due to hypobaric hypoxia exposure.

Cowpea (Vigna unguiculata) is a nutritious vegetable and a key crop in China, encompassing a sizeable cultivation area. However, continuous cropping has led to declines in yield and quality, limiting sustainable development in the protected cowpea industry. This study investigated the effects of combining organic fertilizer with soil conditioner (an amendment containing beneficial microbes and organic components) on protected cowpea production, soil physicochemical properties, and microbial community structure in soils subjected to five consecutive cowpea cropping cycles. The results demonstrated that combined application significantly improved cowpea yield and quality. Specifically, soil pH decreased by 5.4%, while soil organic matter (OM) content increased markedly, especially during the vegetative growth stage, displaying a 70.4% increase. The activities of key soil enzymes, including sucrase (SC), protease (PT), nitrate reductase (NR), dehydrogenase (DHO), and phosphatase, were enhanced, while the urease (UE) activity decreased. Additionally, the combined application improved bacterial and fungal abundance and diversity. Operational taxonomic unit (OTU) richness exhibited positive correlations with various soil nutrient indicators, enzyme activities, and physicochemical properties. Moreover, cowpea protein, carbohydrate, and energy contents were positively correlated with specific soil enzyme activities and nutrient levels. The combined treatment increased the cowpea yield by nearly 32,849kg per ha and protein content by 32.3% compared with applying only organic fertilizer while optimizing the soil microbial community, improving soil structure and fertility, and effectively mitigating the issues of continuous cropping in protected cowpea production.

Polymyxin antibiotics are often the last line of defense against multidrug-resistant Gram-negative pathogens. A key resistance mechanism involves the addition of 4-amino-4-deoxy-L-arabinose (L-Ara4N) to lipid A, mediated by the bifunctional enzyme ArnA. However, the evolutionary rationale and structural basis for ArnA’s domain fusion, hexameric assembly, and catalytic coordination remain mechanistically unresolved. Here, we integrate evolutionary genomics, high-resolution cryo-electron microscopy (cryo-EM), and computational protein design to provide a comprehensive mechanistic analysis of ArnA. Our evolutionary analysis reveals that the dehydrogenase (DH) and formyltransferase (TF) domains evolved independently and were selectively fused in Gammaproteobacteria, suggesting an adaptive advantage. A 2.89 Å cryo-EM structure of apo-ArnA resolves the flexible interdomain linker and reveals a DH-driven hexameric architecture essential for enzymatic activity. 3D variability analysis captures intrinsic conformational dynamics, indicating a molecular switch that may coordinate sequential catalysis and substrate channeling. Structure-based peptide inhibitors targeting the hexamerization and predicted ArnA–ArnB interaction interfaces were computationally designed, offering a novel strategy for disrupting L-Ara4N biosynthesis. These findings illuminate a previously uncharacterized structural mechanism of antimicrobial resistance and lay the groundwork for therapeutic intervention.

This study examined the impact of distance from the road traffic on soil enzymatic activity, which we used as a tool to assess the relationship between soil and common nettle (Urtica dioica L.) used in herbalism and phytotherapy. A section of national road No. 10 (DK10) was selected for the study. Soil and common nettle leaf samples were collected from locations 5 m, 15 m, 25 m, and 100 m away from the road traffic and a control location (C). The activity of catalase (CAT), dehydrogenases (DEH), alkaline phosphatase (AlP), acid phosphatase (AcP), protease (PRO) and β-glucosidase (BG) was examined in the soil. Soil quality indices (RCh, RS, AlP/AcP, GMea, TEI) were calculated based on the enzyme activity results. The leaves of common nettles were tested for chlorophylls a and b (Chl a and b), carotenoids (Car), ascorbic acid (AAC), pH, relative water content (RWC), catalase (CATp) and superoxide dismutase (SOD) activity. Based on the values of Chl a+b, Car, pH, and RWC, the air pollution tolerance index (APTI) was calculated. The activity of the tested enzymes was statistically lowest in soil collected 5 m from traffic compared to the control (C), which was also confirmed by the results of the enzymatic soil quality indicators. In the case of CAT, AlP, AcP, and BG, based on the coefficient of determination (R2), it was found that over 70% of the variability of these enzymes was related to the distance from the road. It was found that the content of Ch a and b, Car, AAC, RWC, and pH was also lowest in soil 5 m away, whereas the activity of the antioxidant enzymes CATp and SOD was highest at this point. The ATPI values determined in common nettle leaf samples collected from locations 5 m, 15 m, 25 m, and 100 m from the road traffic were sensitive to pollution. The results indicate that the distance from the road strongly influenced the changes in the parameters studied. The enzymatic properties of the soil and selected biochemical parameters of common nettle leaves were similar at locations 15 m and 25 m, as well as 100 m and the control. The results of the enzymatic soil quality indicators show that soil 5 m from the road traffic is subject to degradation, and the nettles growing in this location are sensitive to road pollution. Therefore, it is not recommended to collect common nettle leaves from this location for medical or cosmetic purposes.

The widespread occurrence of nano-plastics (NPs) in aquatic environments poses emerging challenges to the pollutant removal performance and ecological stability of constructed wetlands (CWs). This study investigates the performance of calcium-modified (Ca-MBF) and manganese-modified basalt fiber (Mn-MBF) bio-nests as novel substrates to mitigate NP-induced inhibition of CWs. Laboratory-scale CWs were operated for 180 days to evaluate substrate-associated enzyme activities, microbial community structure, and functional gene profiles. Results showed that Mn-MBF bio-nests enhanced the activities of dehydrogenase (DHA), urease (UR), ammonia monooxygenase (AMO), nitrite oxidoreductase (NOR), nitrate reductase (NAR), nitrite reductase (NIR), and phosphatase (PST) by 86.2%, 65.5%, 127.0%, 62.8%, 131.5%, 65.3%, and 107.0%, respectively, compared with the control. In contrast, Ca-MBF bio-nests increased these enzyme activities by 48.6%, 53.5%, 67.0%, 30.6%, 95.0%, 45.3%, and 54.6%, respectively. MBF bio-nests also enhanced microbial diversity, enriched denitrifying and phosphorus-removing bacteria (e.g., Thauera, Plasticicumulans), and promoted extracellular polymeric substance secretion. Functional gene prediction indicated elevated abundances of nitrogen cycle-related genes, thereby enhancing nitrification, denitrification, and phosphorus removal processes. These synergistic effects collectively improved nitrification, denitrification, and phosphorus removal efficiency, with Mn-MBF showing superior performance. This study highlights MBF bio-nests as a sustainable strategy to enhance the resilience and long-term operational stability of CWs in environments impacted by nano-plastic pollution.

This study evaluated the effects of different doses of the herbicide fluroxypyr on soil microbial communities under controlled laboratory conditions. Specific enzymatic activities ((dehydrogenase (DA), urease (UA), catalase (CA), phosphatase (PA)) and quantitative variations in bacterial and fungal populations were measured regarding key physico-chemical soil parameters (temperature, pH, electrical conductivity, moisture, organic matter, ammonium, nitrate nitrogen, and available phosphate content). The effects of the herbicide on the targeted parameters were dose- and time-dependent. Fluroxypyr induced a clear decrease in DA, CA, and PA during the first 14 days after administration, while UA showed a decrease in the first 7 days, followed by a slight increase starting on day 14, closely related to the applied dose. Microbial populations decreased in direct relation to the fluroxypyr dose. Organic matter content exhibited a positive correlation with DA, UA, CA, as well as with microbial populations. In addition, three natural compounds structurally similar to fluroxypyr were identified via 3D virtual screening, demonstrating potential herbicidal activity. Fluroxypyr can alter soil metabolic activity and disrupt microbial communities, thereby affecting soil fertility. Used as a reference in 3D screening, fluroxypyr helped identify three natural compounds with potential herbicidal activity as safer alternatives to synthetic herbicides.

Transboundary intercellular communication mechanisms in the treatment of polyvinyl alcohol (PVA) wastewater by Geotrichum candidume enhanced activated sludge.

Optimized bacterial consortium-based strategies for bioremediation of PAHs-contaminated soils: insights into microbial communities, and functional responses.

Seasonal shifts in climatic conditions can significantly influence biotic and abiotic parameters in wetland ecosystems. This study evaluated the seasonal, spatial, and depth-wise variations in labile organic carbon (LOC) [permanganate oxidizable carbon (POXC), light fraction organic carbon (LFOC), and dissolved organic carbon (DOC)] and soil enzyme activities [β-glucosidase (BG), dehydrogenase (DHA), and amylase] in Deepor Beel sediments. Two-way ANOVA and t-tests revealed that seasonal changes had stronger influences than sediment depth on LOC and enzyme activities, with LOC peaking during the post-monsoon (POM) season. Amylase and DHA activities were higher during the pre-monsoon (PRM) period, while BG activity was higher during POM. During monsoon (MON), enzyme activity declined, likely due to heavy rainfall and reduced biomass cover. Bacterial screening revealed high mean CFU/ml for BG during POM (5.17), and for DHA and amylase during PRM (6.56 and 5.3, respectively). Some sites exhibited few or no enzyme-producing colonies, consistent with biochemical assays and suggesting a bacterial role in enzyme activity. Pearson's correlation indicated positive associations of amylase and BG with POXC during PRM, and between amylase and POXC during POM, highlighting the potential of these enzymes as biological indicators of POXC content. Principal Component Analysis (PCA) further confirmed strong correlations between LOC and soil enzymes. As the first report on LOC and soil enzyme dynamics in Deepor Beel, this study provides a baseline for future research on the area's carbon cycle dynamics and underscores the importance of these parameters in sustainable agriculture, given their role in soil fertility and soil health.

Based on a 31-year consecutive long-term positioning trial of stover return to field， including four different corn stover return methods： stover not returned to field （CK）， stover overgrown （CM）， stover crushed and directly returned to field （SC）， and stover mulched （SM）； the soil nutrient content， extracellular enzyme activity， fungal community structure， and mycorrhizal functional activity were comprehensively analyzed using high-throughput sequencing technology， FUNGuild functional prediction， and ecological network approach. We investigated the effects of different straw return modes on the nutrient content of brown soil farmland， analyzed the characteristics of soil extracellular enzymes and functional activities of fungal communities， and provided a theoretical basis for efficiently improving the soil fertility of brown soil farmland. The results showed that： ① Long-term different straw return treatments （SM， SC， and CM） significantly increased soil fertility， maize yield， and extracellular enzyme activities， and soil organic carbon （SOC）； total nitrogen （TN）； total phosphorus （TP）； total potassium （TK）； alkaline dissolved nitrogen （AN）； effective phosphorus （AP）； quick-acting potassium （AK）； cumulative yield of maize； and the contents of soil glucosidase （β-GC）， cellobiose hydrolase （CBH）， and dehydrogenase （DHA） contents were elevated from 17.0%-42.9%， 3.0%-50.0%， 2.3%-27.9%， 4.4%-11.5%， 11.2%-71.0%， 14.1%-320.8%， 17.1%-153.6%， 6.4%-23.0%， 35.6%-190.7%， 41.9%-58.6%， and 28.8%-773.8%； among them， the CM treatment had the most significant enhancement effect. ② Long-term different straw return treatments changed the structural composition of the soil fungal community， and the relative abundance of fungi in the phylum Periphyton decreased by 29.05%-31.12%， and the phylum Stachybotrys was enhanced by 24.76%-481.10%. The soil pH was an important influencing factor affecting the composition of the fungal community. ③ The results of network analysis showed that the indicator species of different straw return treatments in the long term belonged to different modules， which were significantly correlated with soil nutrient content and enzyme activity， among which Phaeoacremonium and Conocybe enriched in the CM treatment formed specific functional microbial clusters through a strong symbiotic relationship. ④ Functional prediction based on FUNGuild found that long-term different straw return treatments both increased the relative abundance of pathogenic and saprophytic trophic fungi and decreased the relative abundance of saprophytic-symbiotic trophic fungi. Long-term straw return can improve soil fertility and extracellular enzyme activity， increase the abundance of beneficial flora， significantly change the structure and composition of fungal communities， and favor carbon and nitrogen cycling， thus promoting the formation of a suitable environment for crop and fungal growth in brown soils.

Phytoremediation of OTC-Cu/Zn contaminated sediment: Synergetic removal mechanism and microbial community response.

The phytoaccumulation of Fe, Mn, Cu, Zn, and Pb in Tilia cordata flowers and soils from six locations with varying degrees of anthropopressure in Bydgoszcz city and its surroundings (Poland) was assessed. Additionally, metal concentrations and soil enzymatic activity were analyzed. Enrichment Factor analysis revealed significant Zn enrichment at only one locality, supported by a geoaccumulation index value indicating moderate soil pollution. Total metal content in soils correlated with total organic carbon (TOC), while total iron content correlated with the clay fraction (&lt;0.002 mm). Metal concentrations were comparable to the geochemical background levels for soils in Poland. Assessment of total metal contents in the topsoil surface layer from the six locations indicated that concentrations did not exceed permissible limits established by applicable legislation. The study showed that sampling locations influenced the activities of dehydrogenase (DHA), fluorescein diacetate hydrolysis (FDA), β-glucosidase (GL), and arylsulfatase (AR), and these activities correlated more strongly with pedogenic factors than with metal content. No elevated metal levels were detected in the dry mass of T. cordata flowers. Lead content did not exceed 10 mg·kg−1 dry matter, in accordance with World Health Organization (WHO) recommendations. Continued monitoring of trace element levels in soils and T. cordata flowers, particularly in urban environments, is advisable.

Phytoremediation is a plant‐based approach for effective biodegradation of environmental pollutants but its efficacy for MPs mainly remains unknown. In this context, in the present study, the biodegradation of polyethylene terephthalate (PET) and polypropylene (PP) microplastics by alfalfa (Medicago sativa L.) was investigated for one year. Treatment with different types and concentrations of MPs showed no significant effects on alfalfa germination rate and growth. Bacterial communities in the rhizosphere of alfalfa with MPs treatment increased significantly compared to untreated controls. Types of MPs showed no effects on bacterial counts. Dehydrogenase (DHO) enzyme activity in the rhizosphere of plants with MPs treatment was significantly higher than plants without MPs treatment but the concentration and types of MPs showed no significant effects on rhizosphere DHO activity. The mean degradation rate for PET-MPs and PP-MPs was 0.29% and 0.44%, respectively. The increase of MPs concentration in the soil from 2 to 10 g/kg elevated the mean degradation rate from 0.26% to 0.48%. Rhizodegradation of MPs is a consequence of complex interactions between MPs, root exudates and microbial activities in the rhizosphere. Therefore, phytoremediation using alfalfa could be considered as a potential method for in situ removal of MPs from the soil.

High-efficiency immobilization of soil available cadmium by chicken manure and its derivatives: Roles of chemical and microbial property

Numerous studies have focused on dioecious plants and their sex-specific responses to drought stress. However, sexual dimorphism in drought stress responses between male and female Litsea cubeba, a dioecious species significant to the terrestrial ecosystem in China that is frequently exposed to drought conditions, remains insufficiently characterized. In this study, we examined the sex-specific physiological and biochemical responses of L. cubeba to natural drought stress. The results revealed that natural drought induced significant sexual dimorphism in physiological and biochemical traits of L. cubeba. Females exhibited a higher malondialdehyde (MDA) content than males under prolonged drought conditions; females also exhibited significantly higher catalase (CAT) and peroxidase (POD) activities in both leaves and roots compared to males, with the average CAT and POD activities of all varieties increasing by 104.28% and 23.67% in leaves and 51.17% and 174.57% in roots, respectively. Meanwhile, the dehydrogenase (DHA) activity and chlorophyll (chl) and carotenoid levels of females were higher than those of males. The contents of proline (Pro), soluble sugar (SS), abscisic acid (ABA), and jasmonic acid (JA) in females were significantly higher than those in males. Our results demonstrated that females possess a greater tolerance to natural drought stress than males; this is due to their more efficient antioxidant system, better osmotic adjustment, lower chlorophyll degradation rate, and higher concentrations of ABA and JA, which aid in stomatal closure and facilitate the reactive oxygen species (ROS)-scavenging abilities of females in response to drought stress. Our findings provide evidence that dioecious L. cubeba may adopt distinct survival strategies during natural drought events and enhance our understanding of sexually dimorphic responses to drought stress in L. cubeba.

Organic farming could be a promising approach as an agricultural system utilizing available organic materials without retrogradation natural resources. In this study, the effect of four levels of compost (0, 12, 18, and 24 t/ha) on fenugreek plants (Trigoneila foenum-greecum) over two seasons (2021–2022 and 2022–2023) was investigated in combination with different planting timings on a sandy soil. A randomized complete block design with three replications was used for the experiment conducted at the Agricultural Experiment and Research Centre of Minia University, Egypt. The Results showed that fertilizing fenugreek plants with compost significantly increased the vegetative growth traits such as plant height, number of branches/plants and herb biomass. The highest values of soil organic carbon (SOC), 986.3 mg kg-1, dissolved organic carbon (DOC), 21.l6 mg kg-1, dissolved organic nitrogen (DON), 9.43 mg kg-1, microbial biomass-C (59.67 mg kg-1.), -N (24.88 mg kg-1), -P (14.67 mg kg-1), net bacterial [95.3 (×105 cfu g-1)] and fungi [74.32(×104 cfu g-1)] counts were obtained with 24t/ha of compost. Enzyme activities of dehydrogenase (DH), urease and β-glucosidase (βG) increased significantly as the compost rate increased. For planting dates, the beginning of October was the optimal time for fenugreek production in April. For sandy soils with low fertility under arid conditions, organic and inorganic fertilizer use will enhance crop quality and productivity, soil health and soil organic matter build-up.