Sulfur Fertilizer Application Research Articles

Optimizing Nitrogen Nutrient Management for the Sustainable Enhancement of Secondary Metabolites and Yield in Onion Cultivation

This study investigates the impact of nitrogen (N), sulfur (S), and iron (Fe) fertilization on secondary metabolites, particularly quercetin and its forms, in onion bulbs (Allium cepa L.). Field experiments over two years examined four onion varieties with red, yellow, and white colors of bulbs: Kamal, Robin, Pueblo, and Mundo. The parameters investigated included the yield, dry matter content, and average onion weight. The phenolic and flavonoid contents were also analyzed. The free quercetin, bound quercetin, and total quercetin contents were determined using the HPLC method. The results demonstrated notable increases in yield following the application of nitrogen (NH4+) and sulfur (SO42−) fertilizers. Incorporating iron (Fe2+) alongside these fertilizers did not yield a significant impact compared to N+S variant. The phenolic and flavonoid content varied with fertilization, while the quercetin content did not yield statistically significant results. Overall, the study highlights the complex relationship between fertilization practices and secondary metabolite production in onions, emphasizing the need for sustainable intensification in modern agriculture.

The Impact of the Individual and Combined Application of Phosphorus and Sulfur Fertilizers on Potato Tuber Flavor.

Sulfur and phosphorus are important plant nutrients required for potato growth, influencing the synthesis of primary metabolites that serve as the material foundation of potato flavor quality. However, little is known about the effects of sulfur and phosphorus application on potato tuber flavor. This study experimentally compared the effects of the individual and combined application of phosphorus and sulfur fertilizers on the flavor of potato tubers. The research examined the sensory characteristics of flavor under various fertilization methods, investigated changes in the types and contents of volatile flavor compounds, and conducted analyses on flavor precursor compounds. The experimental results showed that the application of phosphorus and sulfur fertilizers, either individually or in combination significantly increased the content of linoleic acid and linolenic acid. After the combined application of phosphorus and sulfur fertilizers, the starch and the reducing sugar content also significantly increased. (E,E)-2,4-Nonadienal and Decanal are closely correlated with fatty acid content. Dimethyl sulfide and Trimethyl sulfide contents are significantly related to methionine content. This also significantly enhances the fatty taste characteristics of the tubers but weakens the potato flavor characteristics. Hence, the application of phosphorus and sulfur can affect the accumulation of primary metabolic products in tubers, thereby affecting flavor quality. Compared with the individual application of phosphorus or sulfur fertilizers, when phosphorus fertilizer is applied at 180 kg·ha-1 and sulfur fertilizer at 90 kg·ha-1 in combination, it can further enrich the roasted flavor characteristics of potatoes and maximize the enhancement of potato flavor quality. This provides valuable theoretical support for achieving high-quality agricultural development.

Key process for reducing grains arsenic by applying sulfate varies with irrigation mode: Dual effects of microbe-mediated arsenic transformation and iron plaque

Sulfate affects the transformation of arsenic (As) in soil and its absorption by plant roots. However, the influence of sulfate and irrigation interactions on the mobility of As in the soil-rice system remains poorly understood. To address this gap, we conducted a pot experiment with varying sulfate levels and irrigation modes to examine their effects on rice As translocation, soil As forms, iron plaque formation, and microorganisms involved in As transformation. The addition of exogenous sulfate significantly reduced grain As levels by a maximum of 60.1%, 46.7%, and 70.5% under flooding (F), flooding-moist alternate (FM), moist (M) conditions, respectively. However, the changes in soil available As did not fully correspond to grains As content. Soil available As was only reduced by sulfate under the FM treatment, which limited grains As accumulation under this condition. The reduction in grains As content under F and M conditions was mainly attributed to sulfate-induced increases in soil pH, which in turn inhibited As translocation and promoted iron plaque formation. Additionally, both irrigation mode and sulfate fertilization independently or interactively influenced the abundance of Sulfuritalea, Koribacter, Geobacter, and Sulfuriferula, thereby affecting the As forms in soil through the Fe/S redox process. Specifically, under F and FM conditions, SO42–-S inhibited Geobacter but stimulated Fe-oxidizing bacteria, possibly resulting in increased As bound to Fe/Mn oxides (As–F3). Under M condition, SO42–-S levels regulated As adsorption and release through the participation of Fe/S cycle bacteria, specifically influencing the adsorbed As fraction (As–F2). Therefore, the addition of SO42–-S hindered As translocation to grains by promoting As sequestration in the iron plaque and facilitating microbe-mediated As immobilization through the Fe/S cycle, which was dependent on soil moisture. These results can be used as a guide for sulfur fertilizer application under different soil moisture with the goal of minimizing rice grain As.

Amino Acid Composition and Biological Value of Irrigated Potato Tubers on Chestnut Soil at Increasing Doses of Sulfur Fertilizers (with NPK)

Application of sulfur fertilizers at the doses of 15 and 30 kg/ha (with NPK) for irrigated potatoes on chestnut soils of Western Transbaikalia is the most effective for production of marketable tubers with the maximum value of bioenergy coefficient. With increasing the doses of sulfur, in spite of the insignificant increase of crude protein content, the amount of amino acids and the index of essential acids significantly increased in comparison with the control and the background. Replacement of limiting sulfur-containing amino acids (methionine + cystine) with leucine was noted. The highest biological value of potato protein at the level of 72–74% was found at the doses of 15 and 30 S kg/ha (with NPK).

The Effect of Various Forms of Sulfur on Soil Organic Matter Fractions and Microorganisms in a Pot Experiment with Perennial Ryegrass (Lolium perenne L.).

This article focuses on the agronomic evaluation of the supplementation of mineral NPKMg fertilizers with elemental sulfur, magnesium, potassium, or ammonium sulfates in pot experiments with ryegrass growing in a sandy Arenosol with very low sulfur content. A benefit evaluation was carried out on the basis of biomass production, crop nutritional status, and changes in the content of soil organic matter fractions. Furthermore, the total number of bacteria, nitrogen-fixing bacteria, and fungi was estimated using the qPCR technique in soil samples after 60 days of ryegrass growth. The combined application of NPKMg and sulfur or sulfate fertilizers significantly increased the summary yield of three cuttings of fresh ryegrass biomass in the range of 32.3% to 82.7%. The application, especially in the form of sulfates, significantly decreased the content of free phenolic acids. Furthermore, compared to the control, i.e., soil with NPKMg applied alone, an increase in the content of glomalin-related proteins and a decrease in the amount of water-soluble organic carbon compounds were observed. Neither the number of DNA marker copy numbers of the total bacterial community nor the nitrogen-fixing bacteria were noticeably different. In turn, the total number of genetic markers for fungi was significantly higher in soils with potassium or ammonium sulfates compared to the control soil. The general results suggest that the application of sulfur fertilizers with NPKMg mineral fertilizer can benefit crops and support soil fertility due to the stabilization of aggregates and the decrease in water-soluble organic compounds.

Effects of Cysteine and Inorganic Sulfur Applications at Different Growth Stages on Grain Protein and End-Use Quality in Wheat.

The aim of this study was to test the significant effects of inorganic sulfur and cysteine on grain protein and flour quality in wheat and to provide a theoretical basis of wheat cultivation techniques with high yield and quality. In the field experiment, a winter wheat cultivar, Yangmai 16, was used, and five treatments were established, i.e., S0 (no sulfur fertilizer application during the whole wheat growth period), S(B)60 (60 kg ha−1 inorganic sulfur fertilizer was applied as the basal fertilizer), Cys(B)60 (60 kg ha−1 cysteine sulfur fertilizer was applied as the basal fertilizer), S(J)60 (60 kg ha−1 inorganic sulfur fertilizer was applied as the jointing fertilizer), and Cys(J)60 (60 kg ha−1 cysteine sulfur fertilizer was applied as the jointing fertilizer). The fertilizer application at jointing stage showed a better influence than basal fertilizer application on protein quality; for the content of albumin, gliadin, and high molecular weight glutenin (HMW-GS), Cys(J)60 was the best among these treatments. An increase of 7.9%, 24.4%, 43.5%, 22.7% and 36.4% was found in grain yield, glutenin content, glutenin macro-polymer (GMP), low molecular weight glutenin (LMW-GS), and S content under Cys(J)60, in relation to the control, respectively. A similar trend was found in the end-use quality, as exemplified by an increase of 38.6%, 10.9%, 60.5%, and 109.8% in wet gluten content, dry gluten content, sedimentation volume, and bread-specific volume, respectively; a decrease of 69.3% and 69.1% in bread hardness and bread chewiness was found under Cys(J)60. In terms of application period, topdressing at jointing stage is compared with base fertilizer, the sulfur fertilizer application at jointing stage showed larger effects on grain protein and flour quality, from the different types of sulfur fertilizer, the application of cysteine performed better than the use of inorganic sulfur. The Cys(J)60 exhibited the best effects on protein and flour quality. It was suggested that sufficient sulfur application at jointing stage has the potential to enhance the grain protein and flour quality.

Nitrogen and sulfur fertilizers promote the absorption of lead and cadmium with Salix integra Thunb. by increasing the bioavailability of heavy metals and regulating rhizosphere microbes.

Fertilization is an effective agronomic strategy to improve the efficiency of phytoextraction by Salix integra Thunb. However, the specific effects of the simultaneous application of nitrogen (N) and sulfur (S) fertilizers in the rhizosphere remain unclear. We investigated the bioavailability of lead (Pb) and Cadmium (Cd) along with the microbial metabolic functions and community structure in the rhizosphere soil of S. integra after the application of N (0, 100, and 200 kg·ha−1·year−1) and S (0, 100, and 200 kg·ha−1·year−1) fertilizers for 180 days. The simultaneous application of N and S fertilizers significantly enhanced the absorption of Pb and Cd by S. integra, whereas this effect was not observed for the single application of N or S fertilizer. The contents of acid-soluble Pb and Cd in the rhizosphere soil significantly increased after either single or combined fertilize applications. The microbial metabolic activity was enhanced by the N and S fertilizers, whereas the microbial diversity markedly decreased. The metabolic patterns were mainly affected by the concentration of N fertilizer. The dominant fungi and bacteria were similar under each treatment, although the relative abundances of the dominant and special species differed. Compared to the N200S100 and N200S200 treatments, the N100S100 and N100S200 treatments resulted in fewer pathogenic fungi and more rhizosphere growth-promoting bacteria, which promoted phytoremediation by S. integra. Redundancy analysis indicated that the pH and nitrate content were the key factors affecting the structure of the microbial community. Collectively, the results suggest interactive effects between N and S fertilizers on the rhizosphere soil, providing a potential strategy for plant-microbial remediation by S. integra.

Optimizing sulfur fertilizer application rate for profitable maize production in the savanna agroecological zones of Northern Ghana

Although several studies have established the importance of sulfur (S) in increasing maize productivity in the savanna agroecological zones (AEZs) of northern Ghana, the economically optimum S application rate is still unknown. In a two-year study at eight locations across the AEZs, we determined the economically optimum S application rate for S-deficient soils. We compared eight S application rates, ranging from 0 to 70 kg ha−1 at 10 kg intervals, for optimal maize productivity and profitability. The study identified 30 kg S ha−1 as the minimum rate that resulted in a plant tissue S concentration above the critical level of 0.15%. Although increasing the S application rate resulted in increases in maize grain yield, application of S beyond a rate of 30 kg ha−1 resulted in increases in maize grain yield that were not statistically significant and leveled off at 50 kg S ha−1. Application rates ≥50 kg ha−1 resulted in a high proportion of the applied S not taken up by the plant and, thus, subject to losses from the soil. Based on agro-input prices at the local level and the farm-gate prices of maize, the greatest potential profit resulting from S application was observed at 30 kg S ha−1, with a projected average maize yield of between ∼4.2 and 5.3 Mg ha−1, representing >90% of the observed yield with the highest S application rate of 70 kg ha−1. Thus, we conclude that, for sustainable and profitable maize production in S-deficient soils of the savanna AEZs of northern Ghana, an S applications rate of 30 kg ha−1 is economically justified.

Response of Sulphur Fertilizer Application to Bread Wheat (Triticum aestivum) Yield and Quality in Kulumsa, Arsi, Ethiopia

Abstract: A field study was conducted during 2013/14 cropping season with the objectives of to study the response of bread wheat to different rates of sulfur fertilizer, to study the effect of Sulphur fertilization on yield and quality of protein of bread wheat and to suggest some recommendations about the optimal rates of sulfur fertilizer application for bread wheat as well as for further sulfur research works. The treatments applied as one factor of six levels of sulphur (0, 20, 40, 60,80 and 100 kg S ha-1 . The treatments were replicated three times in a Randomized Complete Block Design. The experiment was carried out at the Kulumsa Agricultural Research Center on clay textured soil. Data were collected and statistical analysis was done on various characters of the crop. Soil Samples were also taken before and after the implementation of the experiment and chemically analyzed. The analysis of variance for the results of the study revealed among yield and Quality parameters of wheat; Thousand Grains Weight, Grain protein content and wet Gluten were significantly (p≤0.05) affected by rates of S. In addition to Grain yield and Hectoliter Weight were highly significant (p≤0.01) by rates of S. Average over S treatments, each S level brought about significant increase in grain yield and protein over no S. Accordingly, 60 kg S ha-1 further increased yields significantly over control (no N), followed by 40,20, kg S ha-1. Application of 60 kg S/ha increased the grain yield of wheat by 12.64%, 11.39%, 6.44% and 2.52% respectively when compared with the no S application and increased protein contents of wheat by 2.94%, 1.77%, 1.42% and 1.36% respectively when compared with the no S application. However, more systematic investigation should be made based on the detailed analysis of soil fertility, crop characteristics and economic feasibility of recommended treatments in different principal bread wheat growing areas of Ethiopia in order to reach a sound conclusion and recommendation.

Responses of Soil Properties and Bacterial Community to the Application of Sulfur Fertilizers in Black and Sandy Soils

Responses of Soil Properties and Bacterial Community to the Application of Sulfur Fertilizers in Black and Sandy Soils

Subsoil-potassium depletion accounts for the nutrient budget in high-potassium agricultural soils

Continuous potassium (K) removal without replenishment is progressively mining Argentinean soils. Our goals were to evaluate the sensitivity of soil-K to K budgets, quantify soil-K changes over time along the soil profile, and identify soil variables that regulate soil-K depletion. Four on-farm trials under two crop rotations including maize, wheat and soybean were evaluated. Three treatments were compared: (1) control (no fertilizer applied); (2) application of nitrogen, phosphorus, and sulfur fertilizers -NPS-; and (3) pristine condition. After nine years, crops removed from 258 to 556 kg K ha−1. Only two sites showed a decline in the exchangeable-K levels at 0–20 cm but unrelated to K budget. Topsoil exchangeable-K levels under agriculture resulted 48% lower than their pristine conditions, although still above response levels. Both soil exchangeable-K and slowly-exchangeable K vertical distribution patterns (0–100 cm) displayed substantial depletion relative to pristine conditions, mainly concentrated at subsoil (20–100 cm), with 55–83% for exchangeable-K, and 74–95% for slowly-exchangeable-K. Higher pristine levels of exchangeable-K and slowly-exchangeable-K and lower clay and silt contents resulted in higher soil-K depletion. Soil K management guidelines should consider both topsoil and subsoil nutrient status and variables related to soil K buffer capacity.

ВПЛИВ УДОБРЕННЯ ТА ВАПНУВАННЯ НА ПРОДУКТИВНІСТЬ КУКУРУДЗИ НА ЗЕРНО В КОРОТКОРОТАЦІЙНІЙ СІВОЗМІНІ НА ДЕРНОВО-ПІДЗОЛИСТОМУ ГРУНТІ

The results of the influence of doses and forms of limestone ameliorants and fertilization on the maize productivity in the Western Polissia were shown. The ameliorants application on the background of mineral fertilizers increased the indicators of the yield structure and plant survival. The highest results were obtained with the use of 1.5 dose dolomite meal by the hydrolytic acidity of: plants density before harvesting 62.4 ths. pcs/ha, plants height of 229 cm, the weight of an ear was 223 g, the grain yield from an ear was 79.7 %. The limestone ameliorants and fertilizers application also had a positive effect on the yield and pro-tein content in maize grain. According to the obtained data, it was found that the protein content in the grain increased by 1.82–2.89 % in variants with melioration on the background of N120P90K120 compared to the control, and amounted to 9.4–10.5 %. The maximum 10.5 % of the protein content was obtained by the using a 1,0 dose of dolomite meal on the background of mineral fertilization with the addition of sulfur S40 and foliar dressing of the Nutrivant Plus Cereals micronutrient fertilizer (2 kg/ha). The highest yield of 9.04 t/ha was formed by the combined use of 1.5 dose of dolomite meal by the hydrolytic acidity and the recommended rate of mineral fertilizers (N120P90K120). The increase of maize yield compared to control (without fertilizers) was 4.99 t/ha, compared to the background (N120P90K120) – 3.98 t/ha. The grain yield of maize increased by 10.3 % due to the application of sulfur fertilizer (S40) and two-time foliar fertilization with Nutrivant Plus Cereals micronutrient fertilizer (2 kg/ha). The analysis of economic efficiency showed that the cultivation of grain maize was unprofitable at the N120P90K120 application without soil liming; while when using chemical ameliorants, in particular different doses of dolomite meal, on a similar background fertilizer the maize cultivation was profitable (in the range of 6174–16024 UAH/ha) Keywords: chemical ameliorants, doses, fertilizers, yield, maize.

Response of Sulphur Fertilizer Application to Bread Wheat (<i>Triticum aestivum</i>) Growth and Yield in Kulumsa, Arsi, Ethiopia

A field study was conducted during 2013/14 cropping season with the objectives of to study the response of bread wheat to different rates of sulfur fertilizer, to study the effect of sulphur fertilization on growth and yield of bread wheat and to suggest some recommendations about the optimal rates of sulfur fertilizer application for bread wheat as well as for further sulfur research works. The treatments applied as one factor of six levels of sulphur (0, 20, 40, 60, 80 and 100 kg S ha-1. The treatments were replicated three times in a Randomized Complete Block Design. The experiment was carried out at the Kulumsa Agricultural Research Center on clay textured soil. Data were collected and statistical analysis was done on various characters of the crop. Soil Samples were also taken before and after the implementation of the experiment and chemically analyzed. The analysis of variance for the results of the study revealed among the agronomic and yield parameters of wheat; Number of Seedling, Number of Tillers per Plant, 50% of flowering date, Plant Height, spike length, Number of Spikes, Number of Seeds per spike, Total Above Ground Biomass Yield and Harvest Index were non-significant (p> 0.05) influenced by rate of S whereas Thousand Grains Weight, and grain yield were significantly (p≤0.05) affected by rates of S. Application of 60 kg S/ha increased the grain yield of wheat by 12.64%, 11.39%, 6.44% and 2.52% respectively when compared with the no S application. 60 kg/ha is recommended for vertisol at kulmsa.

PENGARUH APLIKASI PUPUK SULFUR DAN JUMLAH SIUNG TERHADAP PERTUMBUHAN DAN PRODUKSI BAWANG PUTIH (Allium sativum L.) SERTA RESIDU SULFUR DI INCEPTISOL KARANGPLOSO

Garlic (Allium sativum L.) is a plant that is often used by Indonesian people in various ways. One of the reasons for the low productivity of garlic in Indonesia is the insufficient use of superior varieties and low S elements in the soil. Furthermore, the use of the number of cloves planted per planting hole will determine the number of populations so that it will affect the growth and production of garlic. The aim of this study was to analyze the effect of S fertilizer and the number of cloves on the growth and production of garlic (Allium sativum L.) and also analysis S residue from S fertilizer and number of cloves. This study used a randomized block design with nine treatment combinations, three levels of sulfur fertilizer doses (0 kg S ha-1, 140 kg S ha-1 and 200 kg S ha-1) and the number of cloves (1 clove, 2 cloves and 3 cloves). The results showed that the application of sulfur fertilizer and the number of cloves had no significant effect on growth parameters (plant height and number of leaves) in garlic plants. However, it significantly increased the diameter of bulbs, fresh bulbs weight and dry bulbs weight respectively by 13.39%, 140.72% and 93.64% to 24.29 mm, 5.97 g plant-1 and 4.57 g plant-1 in the treatment of one number of clove and 140 kg of S ha-1 compared to the treatment of one clove and without S. As well as significant effect on SO42- residues and total S with the highest yield respectively 299.3 ppm and 910 ppm and the lowest yield was obtained in the treatment without S fertilizer.

Soil nitrous oxide emissions most sensitive to fertilization history during a laboratory incubation

A 12 wk laboratory incubation examined the effects of application of various nitrogen (N) and sulfur (S) fertilizers on soil plant-available nutrient levels and nitrous oxide (N2O) gas emissions with respect to soil fertilization history using soils sampled from the University of Alberta Breton Classical Plots. Fertilization history and added fertilizer treatments showed significant effects on N2O emissions and NO3−-N and SO4−-S recovered on ion-exchange resins over the 12 wk. Mean cumulative N2O emissions ranged from 0.43 to 1.18 kg N2O-N ha−1. The relationship between observed total resin-recovered NO3−-N and N2O emissions was not consistent for soils receiving long-term applications of various combinations of N, phosphorus, potassium, and S fertilizers. The N2O emission from two soils with a history of long-term N fertilizer applications but different S fertilization histories was significantly different even though resin-recovered NO3−-N levels were similar. When grouped according to added fertilizer treatments, mean cumulative N2O emissions showed a strong linear relationship with mean resin-adsorbed NO3−-N production. We hypothesize that the differences in the relationship between NO3−-N production and N2O-N emissions for soils with different long-term fertilization histories may be a result of the interaction of N and S oxidation processes. Further, soil fertilization history may significantly influence soil N2O emissions in response to N fertilizers added within the growing season of observation but isn’t often considered in short-term experiments, and this may be a significant source of uncertainty in the estimation of greenhouse gases inventories from agricultural soils.

The response of arsenic bioavailability and microbial community in paddy soil with the application of sulfur fertilizers

Arsenic (As) has been recognized as one of the most toxic metalloids present in the surface soil contaminating food chain and posing threat to human life. Sulfur (S) fertilizer is often supplied in paddy soil for rice growth, but its impact on As mobility and related bacteria remains poorly understood. In this study, a pot experiment was set up with two different types of sulfur treatments (element sulfur and Na2SO4) to evaluate the effect of sulfur fertilizers on As speciation in porewater, As fractions in soil, As accumulation in rice plants. Besides, rhizosphere bacterial composition and functional genes that might influence As mobility were also studied. The results revealed that the addition of 150 mg/kg Na2SO4 decreased As(III) and As(V) concentrations in soil porewater at maturation stage by 77% and 64%, respectively. With the same sulfur content, Na2SO4 was more effective than element sulfur. The addition of sulfur fertilizers promoted rice growth and reduced As accumulation in shoots, further reduced As translocation from root to above-ground parts by 39–59%. The addition of sulfur fertilizers had little effect on genes involved in As metabolism. However, the relative abundance of Fe(III) and sulfate reduction related genera increased with the addition of 150 mg/kg Na2SO4, consistent with the increase of Fe(III) reducing bacteria Geobacteraceae and sulfate reducing gene dsrA. The phenomenon likely influenced the decrease of As concentrations in soil porewater and rice uptake. The outcomes indicate that promoting Fe- and S- reducing bacteria in the rhizosphere by sulfur fertilizers may be one way to reduce As risk in the soil-rice system.

Productivity of spring barley depending on fertilization and liming under the conditions of Western Polissya

There are established doses and forms of limestone ameliorants, fertilizers that are optimal for West Polissya based on experimental data from field and analytical studies and provide the fertility of podzolized sandy soil and ensure obtaining a stable spring barley harvest. There was studied the influence of fertilization (N90P90K90), sulfur fertilizers, foliar fertilizers in various doses and types of limestone ameliorants on the formation of the morphological structure of plants and productivity of spring barley.The highest yield of 4.08 t/ha was provided by the application of 1.5 doses (NG) of dolomite flour on the background of the recommended dose of mineral fertilizers (N90P90K90). The yield increase to control (without fertilizers) was 2.69 t/ha, and to the background (N90P90K90) — 1.65 t/ha.The application of sulfur fertilizers (S40) and two fold foliar fertilization by Nutrivant Plus cereal microfertilizer (2 kg/ha) provided a yield increase by 7.3%

Effects of combined application of phosphorus and sulfur fertilizers on agronomic traits and protein content of supplementary irrigated haricot bean (Phaseolus vulgaris) varieties in Raya Valley, Northern Ethiopia

Haricot bean is primarily grown in Ethiopia for human consumption and export earnings. A market demand for haricot bean, both in the domestic and export market, has triggered the production of haricot bean in selected areas of Ethiopia though its production is constrained by several factors such as poor soil fertility and erratic rainfall. This study was carried out to investigate the combined effect of phosphorus and sulfur fertilizers on yield, yield related traits and protein content of haricot bean (Phaseolus vulgaris) varieties at the research field of Mekoni Agricultural Research Center during 2016/17 cropping season. The experiment was laid out in split plot design where varieties were assigned to the main plots and fertilizer rates to the sub plots in three replications. Three phosphorus (P) rates (10, 20 and 30 kg ha-1) were combined with four sulfur (S) rates (15, 30, 45 and 60 kg ha-1) and applied in combination to Melka Awash-98 and Nasir varieties. Data on phenological, agronomic and quality traits were collected and determined. Partial budget analysis was carried out to assess the profitability of the applications. P-S fertilizer treatments were significantly affected by varieties. Treatments were significantly affected by varieties and the imposed P and S rates. The interaction effect due to variety by fertilizer the two factors significantly affect days to flowering, plant height, hundred seed weight and protein content. Tallest plants, fewer days to flowering and maturity, many pods/plant, heavier seeds, higher grain yield ha-1 and better protein content were recorded where the fertilizer application rate was 20 kg ha-1P and 30 kg ha-1 S for both varieties. Grain yield ranged from 1520 to 3000 kg ha-1 depending on P-S fertilizer rates and varieties. Nasir variety seems to be superior over Melka Awash-98 for most traits except protein content. However, production of Melka Awash-98 under 20 kg ha-1P and 15 kg ha-1 S fertilization tend to be more economical as it resulted in highest net benefit return. Although not profitable, planting Melka Awash-98 using an application rate of 20 kg ha-1P and 30 kg ha-1 S could be suggested for use in the area to ensure earliness and high grain yield.

Evaluation of sulfur and foliar application of Zn and Fe on yield and biochemical factors of cumin (Cuminum cyminum L.) under irrigation regimes

Introduction: Cumin, due to its food and medicinal properties, is one of the important plant species in the world. Moreover, water and nutrition deficiencies are serious abiotic stress factors. So, this experiment was conducted with the aim of investigating the effects of sulfur and foliar application of Fe and Zn on yield and biochemical characteristics of cumin under irrigation regimes. Methods: The experiment was conducted as a split plot on the basis of a completely randomized block design during the 2016-2017 growing seasons with three replications. Experimental factors were arranged in irrigation regimes as main plots at three levels (I1: No stress (control), I2: irrigation based on 40% available water discharge, I3: 80% available water discharge) and foliar application of Zinc (Zn) and Iron (Fe) as subplots [F1: control (water-soluble), F2: Iron, F3: Zinc, F4: Zinc and Iron chelate] and sub-sub plots including sulfur fertilizer [S1: control (no use of sulfur), S2: sulfur fertilizer with Thiobacillus]. Results: Analyzed data showed that total phenol content and flavonoids were enhanced with the increase of drought intensity and the maximum amount was recorded under I3, while I3 caused a substantial reduction in grain yield. Flavonoid and grain yield significantly increased in F4. Total phenol content was the highest in F2 and F3 treatments. Application of sulfur fertilizer resulted in a significant increase in peroxidase, phenol and flavonoids. The highest amount of peroxidase was obtained in I3F4 and I3F3. The largest total soluble sugar (TSS) was resulted by I3S2 and the least by I1S1. Foliar application of Zn and Fe with sulfur fertilizer increased TSS. Conclusion: The present study suggests that foliar application of Fe and Zn and sulfur fertilizer can improve the injurious effects of water deficiency on cumin plant through alteration in yield and biochemical characteristics.

Influence of sulfur fertilization on CuO nanoparticles migration and transformation in soil pore water from the rice (Oryza sativa L.) rhizosphere

The biogeochemical cycling of sulfur in soil is closely associated with the mobility and bioavailability of heavy metals; however the influence of sulfur on the behavior of metal-based nanoparticles has not yet been studied. The influence of S fertilizer (S0 and Na2SO4) applied in paddy soils on CuO NPs behavior in soil pore water was explored in the present study. Synchrotron-based techniques were applied to investigate the migration and speciation transformation of CuO NPs in soil pore water colloids. The application of sulfur fertilizer increased the zeta potential of soil colloids from the rice rhizosphere region and reduced the size of the colloids. Sulfur fertilization decreased the concentration of Cu in soil pore water in the rice rhizosphere region. S0 fertilizer reduced the Cu concentration in soil colloids (by 55.8%–73.5%), while Na2SO4 increased the Cu concentration in soil colloids (by 173.8%–265.1%). Sulfur fertilization changed the spatial distribution of Fe3+ and Cu2+ in colloids, making these ions more likely to be aggregated on the edges of soil colloids. Speciation transformation of CuO NPs happened during the process of migration. The main Cu speciation in the soil colloids were CuO NPs, Cu-Cysteine, Cu2S and Cu-Citrate. Sulfur fertilization increased the proportion of Cu2S (by 40.5%) in soil pore water colloids from the rice rhizosphere region, while the proportion of CuO NPs was reduced (by 18.4%). Sulfur fertilization changed the morphology and elementary composition of colloids in soil pore water, thus influencing the migration of CuO NPs in the soil column through soil colloids.