Percentage Of Nitrogen Research Articles

Nitrogen Gas Saturation in Karst Springs Varies Throughout the Day

This experiment examined the fluctuations in nitrogen gas supersaturation throughout the day in three karst springs (upper, side, and lower) at McNenny State Fish Hatchery, rural Spearfish, Lawrence County, South Dakota, USA. Total gas pressures, oxygen percent saturation, and nitrogen percent saturation were recorded six times/day on eight days over a 26-day period in each of the three springs. Total gas pressure did not vary significantly throughout the day in any of the springs. However, percent oxygen and nitrogen saturation were significantly different throughout the day in all three springs. The highest mean (SE) nitrogen supersaturation value of 118.5 (1.1)% was observed in the lower spring at 07:00. The lowest mean nitrogen supersaturation values were 114.5 (1.1)% at 13:00 in the upper spring, and 114.2 (0.2)% and 113.1 (0.7)% at 15:00 in the side and lower spring, respectively. At 118% nitrogen supersaturation, gas bubble disease is likely to occur in fish, resulting in potentially high levels of mortality if untreated spring water was used for fish production. The results of this study indicate the importance of recording nitrogen gas levels at sunrise or early in the morning, when nitrogen is highest and oxygen is lowest, to obtain accurate and reproducible data.

Scarification in Acetic Acid, Hot Water, and Cold Sand Stratification to Improve Carob (Ceratonia Siliqua L.) Seed Germination

This study was carried out to determine the effects of acetic acid, hot water, and cold sand stratification scarification at different periods on seed germination of carob (Ceratonia siliqua L.) in Salah Alden province. The seeds were collected from Kirkuk province area on September 2016. Carob seeds stratified and not stratified treated by soaking in glacial acetic acid for 20, 40, 60, and 120 min. at lab temperature (25oC). Hot water (100oC) also used for soaking the seeds for 20, 40, 60, and 120 min. Experimental design of Randomized Complete Block Design (RCBD) with 3 replicates, and 10 seeds per each treatment per each replicate were used and the results were compared to non-treated seeds. After soaking the seeds in acetic acid and hot water, they washed thoroughly and sowed in black polyethylene grow bags. The soil used was loamy with added organic matter. After 7 months, data recorded on the germination percent and growth features including plant height, leaf area, total chlorophyll, root length, fresh and dry weight of vegetative parts, nitrogen, phosphorous, and potassium percentages in the plant. The results showed that the treatment with hot water for 60 minutes achieved the highest percent of germination (96.67%), highest leaf area 12.86 cm2, highest root dry weight (0.14 gm.), and nitrogen percent of 5.52%. The treatment for 40 minutes with hot water gave the highest fresh weight of vegetative parts was 18.6 gm. and root fresh weight (7.05 gm.). The treatment with hot water for 120 minutes achieved the highest percent of phosphorous and potassium (0.49% and 2.07% respectively).
 

Influence of Spraying Nano-Curcumin and Nano-Glycyrrhizic Acid on Resistance Enhancement and Some Growth Parameters of Soybean (Glycine max) in Response to Tetranychus urticae Infestation and Drought Stress.

Modern nanotechnology has been credited as one of the most significant inventions of the 21st century. Many agricultural disciplines have been affected by nanotechnology in agriculture. Pest control based on natural compounds needs to be enhanced, and enhancing plant growth under climate change conditions, with increasing periods of drought in many countries, is a very vital aim. Thus, the effect of curcumin nanoparticles (Cu-NPs) and glycyrrhizic acid nanoparticles (GA-NPs) as a foliar application under water deficit on natural infestation with the two-spotted spider mite Tetranychus urticae, plant growth and yield, anatomical and chemical parameters were investigated during this study. The obtained results revealed that drought stress over the two studied seasons significantly increased the population of T. urticae and decreased all morphological and yield characteristics. The application of three mM GA-NPs reduced the mite population average by 39% while using the same concentration of Cu-NPs caused a 33.9% reduction percentage under drought stress. Using 1 mM GA-NPs gave the highest averages of plant height, number of branches, and leaves/plant fresh and dry weight. Moreover, the number of pods, 100 seed weight and seed yield (kg/ha) increased significantly as a result of spraying with GA-NPs under water deficit. From the results, water deficit decreased the values of the leaf and stem anatomical parameters. Treatment with Cu-NPs or GA-NPs under drought stress increased the thickness of mid-vein, xylem, and phloem tissues. Likewise, such treatment increased stem diameter due mainly to the increase in the thickness of cortex, phloem, and xylem tissues compared with the control. Spraying plants with GA-NPs at 1 mM increased the percentages of nitrogen, phosphor, and potassium in seeds in addition to total chlorophyll. Moreover, glutamate, aspartate, leucine, arginine, Lysine, glycine, tyrosine, tryptophan, and methionine concentrations did not differ significantly (p > 0.05) in response to all the studied levels of Cu-NPs or GA-NPs either under normal irrigation or drought condition. In light of these findings, researchers and producers should apply and test both Cu-NPs and GA-NP as nano-fertilizer natural sources on economically viable crops.

The role of fractionation of humic acids and spraying with Azolla extract on vegetative growth indicators growth of sunflower crop (Helianthus annuus L).

A field experiment was carried out during the spring season of 2022 at a farm in the AlKhader district 30 km south of Samawah. The experiment was conducted to study the role of fractionation (30 kg H-1) of humic acids for three batches (First batch, Second batch and Third batch) and spraying with Azolla extract using four concentrations ( 0%, 20%, 40%, 60%), on the vegetative growth indicators of sunflower. The treatments were arranged as a split-plot design with two plots, the fractionation (30 kg H-1) (Al-Mughayer, 2019) of humic acids in the main plot and Azolla spray concentrations in the second plot, using three replications .The results showed a superiority in the second batch for the percentage of nitrogen in the leaves with an average of (1.27%) and did not show significant differences in the plant height, number of leaves per plant, leaf area and stem diameter. Foliage and stem diameter were (34.06 leaves -1, 9514 cm2 one plant and 28.14 mm) for the characteristics, respectively, while the spraying concentration of 60% was superior in the percentage of nitrogen in the leaves with an average of (1.25%). The interaction between the study factors was high significantly, as was (40% Azolla extract at the second batch) the highest average of nitrogen content in the leaves, which was up to (1.30%).

Efficiency of Some Herbicides and Fungicides on Management of Common Bean Damping-off and Root-rot Diseases

The three tested herbicides and fungicides caused significant inhibitory effect on the growth of Fusarium solani and Rhizoctonia solani the causal of common bean damping-off and root-rot diseases compared with control treatment. This inhibition was gradually increased by increasing the concentration of the tested herbicides and fungicides. Moreover, the fungus F. solani was greatly affected by the tested herbicides and fungicides than the fungus R. solani. Furthermore, the tested fungicides were more efficient than the herbicides in this regard. There was significant decrease in both damping-off and root-rot severity with significant increase in the survived plants due to the treatment with the tested herbicides and fungicides. No damping-off and root-rot were recorded in case the tested herbicides, fungicides and non-infested soil. Highest percentages of damping-off, root-rot and lowest survived plant were recorded in case of soil infested with any of the two pathogens. In addition, the combination between the tested herbicides and fungicides with any of the tested pathogens resulted in significant reduction to damping-off and root-rot severity with significant increase in the survived plants compared to plants grown in soil infested with any of the two tested pathogens and did not receive such a treatment. The treatment with any of the tested herbicides and fungicides and grown in soil infested with any of the two pathogens resulted in remarkable increase in the total phenolic compounds compared to the values of plants grown in soil infested with any of the two causal fungi (control plants). Gradual increase in the values of total phenolic compounds was occurred by increasing the time of inoculation with the pathogens and the highest increase in the total phenolic compounds was occurred by the tested fungicides compared with the tested herbicides. The percentages of the estimated nitrogen and protein content in common bean green seeds were increased due to the treatment with the tested herbicides and fungicides compared with the green seeds of plants grown in soil infested with any of both pathogens. The tested fungicides caused considerable increase in the percentages of total nitrogen and protein when compared to the tested herbicides.

Enhancing growth and production of carrot plant by spraying aqueous barley sprouts extract, trehalose, and calcium

This research was implemented at vegetable field of the College of Agricultural Engineering Sciences - University of Baghdad during fall seasons, 2018 and 2019. The experiment was conducted using factorial within Randomized Complete Block Design arrangement with three factors and replicates (3X3X2). The aqueous barley sprouts extract (B0, B1) (0, 100 g.L-1) represented the first factor. Trehalose (T0, T1, T2) (0, 50, 75 mmole. L-1) represented the second factor. Calcium (C0, C1, C2) (0, 1, 2 ml.L-1) represented the third factor. The research objectives are assessing the impact of the mentioned factors and their interaction on carrot growth and production. Results showed the superiority of three ways interaction treatment B1T2C1 in producing significant increases nitrogen percent in leaves (2.857, 2.9%), roots (1.273, 1.283%), and carrot production (161.6, 159 ton. ha-1) for both seasons respectively in compare with control treatment B0T0C0.

Yucca schidigera extract depressed ammonia emission in manure incubation and green-house gases release in artificial rumen of cows

The influences of ammonia (NH3) and greenhouse gas (GHG) emissions from livestock on environment recently become a major concern of the worldwide. The objective of the study was to evaluate the effects of Yucca schidigera extract (YSE) on ammonia emission in manure and the release of green-house gases including methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2) in artificial rumen of cows. Addition of YSE significantly decreased ammonia nitrogen (NH3-N) concentration (P < 0.01) and increased the percentage of total nitrogen (N) (P < 0.005) in manure incubation. The populations of total aerobic bacteria were significantly decreased by the addition of YSE with 1% and 2% (P < 0.05), while the populations of Lactobacilli were significantly increased in dose-dependent manner (P <0.001) in manure. In 1-12 h and 13-24h of ruminal fermentation in vitro, the yields of CH4, CO2 and N2O were dose-dependently reduced by the addition of YSE (P < 0.05). Results showed that YSE inhibit ammonia emission in manure and the release of green-house gases in artificial rumen of cows.

Toward strategical bottom-up synthesis of carbon materials with exceptionally high basal-nitrogen content: Development of screening techniques

Selective doping of nitrogen-containing functional groups in the basal plane of carbon materials is the most promising technique for enhancing performances and stability significantly for various applications such as catalysts and electrodes. Reported carbon materials with controlled basal nitrogen are generally synthesized on substrates, leading to low productivity and high cost. Therefore, simple preparation methods for selective doping of nitrogen in the basal plane of carbon materials without substrates are in great demand. This work achieved that simple heat treatment of indolizino[6,5,4,3-ija]quinoline (IQ) at 973 K formed a carbon material with an exceptionally high basal-nitrogen content (98-92%). The highly selective doping of basal nitrogen was attained because of the presence of stable tertiary nitrogen in one pentagon and two hexagon rings of IQ. Screening precursors for preparing carbon materials with a high basal-nitrogen content was conducted to minimize research costs. Screening of precursors by molecular dynamic simulation with reactive force field and formation energies of scission of C–N bonds revealed that IQ was the best precursor to maintain the high percentage of tertiary nitrogen in the basal plane after carbonization because of the high stability of C–N bonds in IQ. Thus, strategic synthesis is now possible using the screening techniques.

Magnetron Sputtering of Transition Metal Nitride Thin Films for Environmental Remediation

The current economic and ecological situation encourages the use of steel to push the technological limits and offer more cost-effective products. The enhancement of steel properties like wear, corrosion, and oxidation resistance is achieved by the addition of small amounts of chemical elements such as Cr, Ni, Si, N, etc. The steel surface can be protected by different treatments such as heating and coating, among others. For many decades, coatings have been an effective solution to protect materials using thin hard films. Several technologies for thin film deposition have been developed. However, some of them are restricted to certain fields because of their complex operating conditions. In addition, some deposition techniques cannot be applied to a large substrate surface type. The magnetron sputtering deposition process is a good option to overcome these challenges and can be used with different substrates of varying sizes with specific growth modes and for a wide range of applications. In this review article, we present the sputtering mechanism and film growth modes and focus on the mechanical and tribological behavior of nitride thin films deposited by the magnetron sputtering technique as a function of process conditions, particularly bias voltage and nitrogen percentage. The biomedical properties of transition metal nitride coatings are also presented.

Mechanical and Microstructural Analysis of Friction Surfaced Aluminum Coatings on Silicon Nitride Ceramic Substrates

The lack of suitable techniques for joining Si_{3}{text{N}}_{4} ceramics with metals has limited the usage of this otherwise outstanding material for composite applications. In this study, aluminum AlMgSi0.5 (EN AW-6060) was coated onto silicon nitride Si_{3}{text{N}}_{4} ceramic substrates using friction surfacing technology. Experimental work revealed that the harmful effects of thermal shock (e.g., substrate cracking, coating delamination) observed with other material combinations can be avoided by selecting materials with a low coefficient of thermal expansion, low Young’s modulus and high thermal conductivity. Design of experiments derived models for coating thickness and bonding strength fit the data well (i.e., the regression model accounts for most of the variation in the response variable). Whereas the coating thickness is predominately dependent on the rotational speed used, the bonding strength is also affected by the traverse speed. Coating thicknesses upto 2.03 mm and bonding strengths of 42.5 MPa were achieved. Deposition rates exceed those of physical vapor deposition by a magnitude of ×1000 and bonding strength is on-par with thin-film metallization. Scanning transmission electron microscope analysis revealed formation of a glassy phase at the interface. Using energy-dispersive X-ray spectroscopy analysis high silicon and oxygen content with smaller percentages of aluminum and nitrogen were detected. High-resolution transmission electron microscope imaging revealed no distinct lattice structure leading to the assumption that the composition is predominantly amorphous and consists of SiAlON.

Investigation the activities of photosynthetic pigments, antioxidant enzymes and inducing genotoxicity of cucumber seedling exposed to copper oxides nanoparticles stress

The anthropogenic increment of metallic nanoparticles in the agricultural environment may contaminate vegetables through foliar uptake. This study investigates the impact of cuprous and cupric nanoparticles (100, 200 and 400 mg L–1) on the early growth stages of cucumber plants and assessed their phenotypical and physiological effect. The potential phytotoxic effect of copper oxides NPs, as air-induced stress, was studied on plant growth, photosynthetic pigments and antioxidant systems in Cucumis sativus L. in addition to assessing inducing genotoxicity. The results showed that the foliar application of both Cu2O and CuO nanoparticles causes a decrease in seedling height, root length, average leaf area and RWC. Chlorophylls contents and nitrogen percentage on cucumber leaves were reduced while chlorophyll ratio, carotene content, electrolyte leakage, Fe and Cu contents were increased in the leaves by exposing them to Copper NPs. While Cu-NPs inhibit SOD and POD activities, CAT and MDA activities are promoted by applying copper oxides. At the same time, just the maximum doses of both oxides decreased APX activity. CuO nanoparticles induce genotoxicity and negatively affect cucumber seedlings' growth and physiological processes more than Cu2O.

Simultaneous removal of carbon, nitrogen, and phosphorus from landfill leachate using an aerobic granular reactor

In this study, aerobic granular reactor (AGR) was used to treat landfill leachate by changing the concentrations of chemical oxygen demand (COD) (668 ± 110-1149 ± 93 mg/L), ammonia (NH 3 –N) (30 ± 3.3-48 ± 1.3 mg/L), and phosphorus (PO 4 –P) (147 ± 18-221 ± 17 mg/L). The average COD removal was gradually reduced from 81 to 75%, increasing COD concentrations from 668 ± 110 to 1149 ± 93 mg/L. In phase I, the maximum removal of COD (94%) and NH 3 –N (85%) were observed at influent concentrations of 668 ± 110 mg/L and 30 ± 3.3 mg/L, respectively. Significant removal of PO 4 –P was observed, resulting in a maximum of up to 87%, further reducing up to 34% due to an increase in influent PO 4 –P concentration. The SVI 30 reduced from 77 mL/g to 24.15 mL/g towards the end of phase III indicates the formation of granular biomass. The stability of AGR was also investigated in extreme conditions like shut-down and shock-loading phases. The treatment of real leachate diluted with wastewater ( ∼ 20:80% v/v) in AGR showed a significant COD, NH 3 –N, and PO 4 –P removal of 62%–65%, 61%–93%, and 56%–64%, respectively. Mass balance analysis indicated that the AGR requires a lower nitrogen percentage for microbial assimilation than the COD and phosphorus. Proteobacteria and Planctomycetes were identified as the predominant (80%) bacterial community in aerobic granules responsible for removing COD, NH 3 –N, and PO 4 –P from leachate using AGR. The maximum biodegradation rate ( r max ) and half-saturation constant ( K s ) of COD in AGR were determined as 123.5 mg/L h and 309 mg/L, respectively. • Aerobic Granular Reactor (AGR) successfully treated landfill leachate. • Carbon, nitrogen, and phosphorus simultaneously removed using AGR. • A decrease in sludge volume index (SVI 30 ) indicates granule formation. • AGR showed better performance at higher shock loading of leachate. • Proteobacteria and Planctomycetes are predominant species in AGR.

Evaluation of Nitrogen Source Uptake by the Bivalve Nuttallia olivacea Fed with 15N-Labeled Diatoms.

Marine diatoms are an important food resource for bivalves, but few experimental studies have evaluated diatom assimilation by bivalves. We conducted a laboratory experiment to investigate the ability of the suspension-feeding bivalve Nuttallia olivacea to utilize three common diatom species (planktonic diatoms Thalassiosira pseudonana and Skeletonema dohrnii and the benthic diatom Entomoneis paludosa) as food labeled with heavy nitrogen stable isotope (15N) by incubation in medium containing Na15NO3. The percentage of food-derived nitrogen in the organs of the bivalves increased over time, confirming that the bivalves were taking up dietary nitrogen from diatoms. The proportion of food-derived nitrogen from diatoms to bivalves appeared to be higher in planktonic species than in benthic species. However, it is possible that the benthic diatom intake by the bivalves in this study was underestimated because the substrate was not disturbed as would occur under field conditions. The percentage of food-derived nitrogen in bivalve organs tended to be highest in the digestive diverticula, followed by the foot, mantle, and siphon, regardless of diatom type. These findings suggest that N. olivacea may preferentially distribute nitrogen to organs other than the siphon, which is prone to continuous loss by fish predation.

Patterns in Foliar Isotopic Nitrogen, Percent Nitrogen, and Site Index for Managed Forest Systems in the United States

Patterns in foliar nitrogen (N) stable isotope ratios (δ15N) have been shown to reveal trends in terrestrial N cycles, including the identification of ecosystems where N deficiencies limit forest ecosystem productivity. However, there is a gap in our understanding of within-species variation and species-level response to environmental gradients or forest management. Our objective is to examine the relationship between site index, foliar %N, foliar δ15N and spectral reflectance for managed Douglas-fir (Pseudotsuga menziesii) and loblolly pine (Pinus taeda) plantations across their geographic ranges in the Pacific Northwest and the southeastern United States, respectively. Foliage was measured at 28 sites for reflectance using a handheld spectroradiometer, and further analyzed for δ15N and N concentration. Unlike the prior work for grasslands and shrubland species, our results show that foliar δ15N and foliar %N are not well correlated for these tree species. However, multiple linear regression models suggest a strong predictive ability of spectroscopy data to quantify foliar δ15N, with some models explaining more than 65% of the variance in the δ15N. Additionally, moderate to strong explanations of variance were found between site index and foliar δ15N (R2 = 0.49) and reflectance and site index (R2 = 0.84) in the Douglas-fir data set. The development of relationships between foliar spectral reflectance, δ15N and measures of site productivity provides the first step toward mapping canopy δ15N for these managed forests with remote sensing.

Life stage and taxonomy the most important factors determining vertebrate stoichiometry: A meta-analysis.

Whole‐body elemental composition is a key trait for determining how organisms influence their ecosystems. Using mass‐balance, ecological stoichiometry predicts that animals with higher concentrations of element X will selectively retain more X and will recycle less X in their waste than animals with lower X concentrations. These animals will also store high quantities of X during their lives and after their deaths (prior to full decomposition). Vertebrates may uniquely impact nutrient cycling because they store high quantities of phosphorus (P) in their bones. However, vertebrates have diverse body forms and invest variably in bone. Current analyses of vertebrate elemental content predominately evaluate fishes, typically neglecting other vertebrates and leaving much of the diversity unexplored. We performed a systematic review and identified 179 measurements of whole‐body percent phosphorus (%P), percent nitrogen (%N), and N to P ratio (N:P) from 129 unique species of non‐fish vertebrates (amphibians: 39 species; reptiles: 19 species; birds: 27 species; mammals: 46 species). We found that %P (mean: 1.94%; SD [standard deviation] = 0.77) and N:P (mean: 12.52) varied with taxonomy and life stage, while %N (mean: 10.51%; SD = 3.25) varied primarily with taxonomy. Habitat, diet, and size had small and inconsistent effects in different groups. Our study highlights two research gaps. Life stage, which is frequently neglected in stoichiometric studies, is an important factor determining vertebrate %P. Furthermore, amphibians dominate our dataset, while other vertebrate taxa are poorly represented in the current literature. Further research into these neglected vertebrate taxa is essential.

Nitrogen balance and microbial protein synthesis in dairy cows fed with peanut meal to replace soybean meal.

This research was carried out to evaluate the effect of replacing dietary soybean meal with peanut meal, on intake and digestibility, microbial protein synthesis, and nitrogen balance in lactating cows. Twelve crossbred Holstein × Gyr cows at 84days in milk (DIM) were distributed in a triple 4 × 4 Latin square. The treatments consisted of increasing peanut meal levels (0, 330, 670, and 1000g/kg dry matter basis) in replacement of soybean meal in the diet. Replacing soybean meal with peanut meal had no effect on the intake and digestibility of dry matter and nutrients. Nitrogen balance and percentage of retained were similar among treatments. Microbial nitrogen synthesis and microbial protein synthesis efficiency were similar among treatments. Thus, in regions where its cost is lower, peanut meal can totally replace soybean meal in dairy cow diets without affecting nitrogen balance and microbial protein synthesis.

EVALUATION OF WATER STRESS AND CO-INOCULATION OF AZOSPIRILLUM BRASILENSE AND RHIZOBIUM TROPICI IN BEANS (PHASEOLUS VULGARIS L.)

Climate change has caused major changes in abiotic factors, with water stress as the greatest threat to agricultural production. The measures aimed at alleviating the problems caused by this limiting production factor have occurred through the adoption of sustainable strategies, especially microbial biotechnology, which uses the interactions between the microorganism and the plant, ensuring productive quality and inducing plant resistance to stresses biotic and abiotic. The objective of the present work was to evaluate the biological nitrogen fixation and the development of bean seedlings, with co-inoculation of two types of inoculants, which were subjected to water stress by different pot capacities. The experiment was conducted in a greenhouse, at Universidade Paranaense - UNIPAR, from April to June 2019. The experimental design was completely randomized (DIC), with 5 replications, 16 treatments and 80 experimental units. The cultivar used was SCS Riqueza. The parameters evaluated were pot capacity (25%, 50%, 75% and 90%); small, large and total nodules, shoot and root length, dry and fresh weight, total carbon and nitrogen. The evaluation of the morphological parameters of the bean seedlings indicated that the co-inoculation technique promoted beneficial effects for the dry mass parameters of shoot, nodule and root. The analysis of the percentage of carbon and nitrogen in the tissues of the seedlings provided an increase in the concentration of these elements in treatments that involved co-inoculation (Azospirillum brasilensis and Rhizobium tropici) with pot capacities of 25 and 75% (CV), demonstrating that the association of microorganisms is beneficial in the limiting water situation.

Spatial and Temporal Variability of the Microbiological and Chemical Properties of Soils under Wheat and Oilseed Rape Cultivation

The size of the microbial biomass and the activity of soil enzymes are among the most sensitive indicators of agricultural land quality. The aim of this study was to determine the spatial and temporal variability of microbial biomass, the activity of dehydrogenase (DHA) enzyme and the concentration of micro- (Na, Mg and Ca) and macroelements (Cu, Zn, Mn and Fe) in the soil, collected from 37 measurement sites (depth 0–30 cm) in a 40-hectare field during two growing seasons (wheat and oilseed rape). The percentage of nitrogen (%N) in the wheat grain and rapeseeds was also determined. Mapping the spatial distribution of the microbial biomass, the level of DHA activity and the concentration of the selected elements was used to assess the soil productivity. All tested soil parameters exhibited temporal and spatial variability. The creation of raster maps showing the distribution of the tested parameters allowed the observation of a higher nitrogen content in wheat grains in the south-western part of the field, with high values of DHA activity, bacterial biomass and soil pH. In the case of oilseed rape, plants grown in the northern part of the field were characterized by a higher nitrogen content in the grain, where the soil was characterized by a higher content of fungal biomass. On the basis of the obtained research results, a positive, statistically significant correlation was also shown between the biomass of bacteria and the level of DHA in the soil under the cultivation of both wheat and rape. The cultivation of both crops had a significant impact on the size of the microbial biomass pool and on the DHA activity level but did not affect the concentration of the nutrients in the soil. High concentrations of the analyzed elements at the measuring points correlated with a greater %N content in the grain/seeds of the crops harvested at those locations in the field. The results conclude that the mapping of the physicochemical parameters, microbial biomass and activity on the field permits the development of an effective strategy for maintaining sustainable soil productivity through the appropriate management of agricultural practices and the better approximation of mineral fertilization.

Effect of CuSO4 and seaweed extract on the nutritional status of grafted local lemon seedlings Citrus limon L. on aurantifolia

Citrus aurantifolia rootstock seedlings were treated with seaweed extract and copper sulfate. Seaweed extract (ground feed) was added during the growing season at four levels (0, 10, 20, 30 ml seedlings-1) and copper sulfate sprayed at four concentrations (0,5, 10, 15 ml L-1). The results showed that the treatment of lemongrass seedlings grafted on rootstock aurantifolia with seaweed extract and spraying with copper sulfate affected the nutritional status For seedlings (percentage of nitrogen in shoots (%), percentage of phosphorous in shoots (%), percentage of potassium in shoots (%), content of leaves of copper (mg. kg-1), iron content of leaves (mg The results also showed that the addition of marine algae extract at a concentration of 30 ml interfering with spraying with copper sulfate at a concentration of 15 ml L-1 is recommended to improve the vegetative, root and nutritional growth of lemon seedlings and its content of macro and micro nutrients.

Effects of Cricket Frass Biofertilizer on Growth of Spring Onion (Allium Fistulosum L.) and Physicochemical Properties of Soil

Objective: This study aims to assess the effects of cricket frass biofertilizer on the growth and yield potential of spring onion (Allium fistulosum L.) and its residual effects on physicochemical properties of the soil in greenhouse and field conditions. Methods: 7 treatments namely cricket frass (0t/Ha, 5t/Ha, 10t/Ha, 15t/Ha, and 20t/Ha), poultry manure (15t/Ha) and cattle manure (15t/Ha) were used and replicated 3 and 4 times in field and greenhouse conditions respectively. Plots of 1m2 arranged in a randomized complete block design for field experiment and pots with 5kg of soil laid out in a completely randomized design for the controlled experiment were used. Spring onion transplants were maintained in both trials for 16 weeks with uniform agronomic inputs. Growth and yield were assessed based on plant height, crop growth rate, number of leaves per plant, plant fresh weight, plant dry weight and root to shoot ratio. The effect of frass on soil was scored based on the percentage of organic carbon, nitrogen, phosphorus, and potassium at the start and end of the experiment. The data was assessed for normality (Shapiro-Wilks test) and subjected to analysis of variance at P<0.05 using R-statistical software. Treatment means were separated using fishers-protected least significant different. Results: Frass application increased growth and yield traits in both trials with the exception of the number of leaves per plant, regardless of the dosage. Frass at 15t/ha outperformed all other treatments and competed favorably against conventional manures obtained from poultry and cattle. Frass bio-fertilizer significantly increased the organic carbon, phosphorus, potassium, calcium and magnesium content of the soils. Frass contained adequate nutrients in labile forms that contributed to growth and yields. This significance can also be linked to the presence of growth promoters and stimulation of microbial population in soils, which is characteristic of insect manures. The high levels of nutrients in the soil after planting confirms frass as an amicable soil amendment that buffers and supports soil properties. Conclusion: Cricket frass biofertilizer is a valuable bio-fertilizer that has the potential to improve the quality of soils and support the growth and yields of notable kitchen vegetables such as onions.