Inorganic Nitrogen Fertilizer Research Articles

Impact of inorganic nitrogenous fertilizers and FYM combinations on plant height at various phases of rice growth and combinations on number of tillers per hill at various stages of effective tillers per hill during rice harvest (Oryza sativa L.)

A pot culture experiment entitled “Impact of inorganic nitrogenous fertilizers and FYM combinations on plant height at various phases of rice growth and combinations on number of tillers per hill at various stages of effective tillers per hill during rice harvest (Oryza sativa L.)” was conducted at Institute of Agricultural Sciences farm, Siksha ‘O’ Anusandhan (Deemed to be University), Bhubaneswar Odisha. on sandy loam soil during kharif 2018-2019. The experiment consisted of eight treatments viz. T1-Control, T2- 50% RDF, T3-50% RDF + FYM @ 5 t ha-1, T4-75% RDF, T5-75% RDF + FYM @ 5 t ha-1, T6- 100% RDF ( NPK 80:40:40), T7-100% RDF + FYM @ 5 t ha-1 and T8-150% RDF. The experiment was laid out in a Randomized Block Design with three replications. The results revealed that highest and significant values were recorded with respect to growth parameters i.e., plant height, number of tillers per hill, effective tillers per hill and yield attributes i.e., number of panicles per hill, panicle length, number of filled grains 1000 seed weight (test weight) in the treatment that received 100% RDF + FYM @ 5t ha-1. Combination of FYM (5 t ha-1) with lower levels of RDF (50 and 75% RDF) also registered higher increase in the above parameters as compared to the application of inorganic fertilizers alone with the corresponding levels. Grain and straw yields followed the same trend as that of growth parameters and at higher levels of nitrogen in the inorganic form (150 % RDF) the values of the various parameters including grain and straw yield were significantly lower than the treatment where 100% RDF +FYM @ 5 t ha-1was applied.. More nutrient content (N, P, K) in grain and straw was observed with the application of 100% RDF + FYM @ 5t ha-1 as compared with 100 and 150% RDF. With the combined application of 100 percent RDF as an inorganic source and 5tha-1 FYM as an organic source, improvements in physico-chemical characteristics such as organic carbon, bulk density, porosity, and accessible macro nutrients (N,P,K) were found.

The growth and yield responses of two bean cultivars to organic and inorganic nitrogen sources

Abstract. Pangaribuan DH, Ermawati, Suryani NMW, Maria WS. 2022. The growth and yield responses of two bean cultivars to organic and inorganic nitrogen sources. Biodiversitas 23: 1677-1682.The productivity of beans is increased by selecting the best cultivar and applying fertilizers according to the needs of the plant. In addition,the application of high-yielding cultivar and N fertilizers with the right dosage could be used to increase the yield. Therefore, the objective of thisstudy is to determine the effect of nitrogensources on the growth and yieldof two bean cultivars. A5×2 factorial treatment was usedin a randomized block design with three replications. The first factor is the Perkasa and Lebat-3 cultivar, the second is organic and inorganic nitrogen fertilizer, namely control, urea 100kgha-1, as well as 10, 20, and 30% concentrationsof liquid organic fertilizer from leucaena leaves. The results showed that the use of liquid organic fertilizers derived from leucaena could be used as an alternative to nitrogenfertilization. Furthermore,the 20% concentrationtreatment producedthe highest number of trifoliate leaves (8.81 leaves) and dry weight (4.52 g). Based on the results,the use of 20% liquid organic fertilizer withPerkasa cultivar showed the best effect on the number of pods per plant (13.38),and yield(846.67 kg ha-1). The technology of liquid organic fertilizers from leucaena leaves could be recommended for bean organic production.

Characterization of Mollisols after Long-Term N Fertilization at Successive Rates in Continuous and Rotated Corn Systems

Modern agricultural systems rely on inorganic nitrogen (N) fertilization to enhance crop yields, but its overuse may negatively impact soil properties. Soil properties to a depth of 90 cm were studied after 36 years of inorganic N fertilization at successive rates of 0, 202, and 269 kg N ha−1 (N0, N202, and N269) in continuous corn production [Zea mays L.] (CCC), and the corn (Cs) and soybean [Glycine max (L.) Merr.] (Sc) phases of a corn-soybean (CS) rotation. Experimental plots were arranged as a split-plot in a randomized complete block design with three replications. High levels of N fertilization under CCC acidified the topsoil (N0 pH 6.6 vs. N269 pH 4.9), and increased the nitrate level eight-fold compared to unfertilized controls. Under CCC, N0 had more than twice the available phosphorus level (P) and 40% more potassium (K) than the fertilized soils. Though treatments did not impact the soil organic carbon (SOC) content, water aggregate stability (WAS) decreased during the soybean phase of the rotated treatment (Sc) when compared to CCC. Fertilization affected soil bulk density (BD), which decreased by 5% from N0 to N269 across rotations. Averaged since the start of the study, corn yields increased by 60% with N fertilizer use compared to the unfertilized controls (N0). The corn grain yield benefited from the rotation with soybeans rendering 17% more grain yield in Cs than in CCC. Yet this benefit rose to 45% more grain yield on average, when no N fertilizer was used in Cs. Our results showed that there are important trade-offs with N fertilization and long-term use of corn monocultures, as its long-term use, even in the fertile and resilient soils on the Midwestern U.S., has led to P and K depletion, soil acidification, and potentially exacerbated N losses to the environment.

The inorganic nitrogen fertilizer equivalency of hairy vetch (Vicia villosa Roth) as a winter green manure in Kanto and Tohoku district, Japan

ABSTRACT It is well known that legume green manure (GM) supplies nitrogen (N) to succeeding crops. However, in Japan, there are few experimental field studies that have quantitatively evaluated the effect of GM on the N supply. To estimate the inorganic N fertilizer equivalency of GM for the succeeding corn crop, two field experiments were conducted in 2012 at Morioka, Tohoku district (cool climate region) and in 2014 at Nasushiobara, Kanto district (warm temperate region). Each experiment had a split-plot design with a factorial arrangement of two cropping systems, hairy vetch [HV; Vicia villosa Roth] GM and conventional cultivation, with four N fertilizer treatments (0, 75, 150, and 225 kg N ha−1). In both sites, GM increased the N uptake and, as a result, the shoot yield of the succeeding forage (silage) corn. The apparent N recovery rates of HV shoot were 64% at Morioka and 24% at Nasushiobara. The inorganic N fertilizer equivalency rates of HV shoot were 82% at Morioka and 104% at Nasushiobara. In conclusion, by introducing HV as a GM, we can reduce the amount of inorganic N fertilizer applied to the succeeding corn crop with the same amount as at least 80% of N uptake in HV shoot.

Biochar Applied with Inorganic Nitrogen Improves Soil Carbon, Nitrate and Ammonium Content of a Sandy Loam Temperate Soil

Biochar is suggested to improve soil properties. However, its combination with inorganic nitrogen (N) fertilizer in temperate soils is not well understood. This study compared the effect of fertilizer N-biochar-combinations (NBC) and fertilizer-N (FN) on total soil N (TSN), soil organic carbon (SOC), soil nitrate (NO3−–N), and ammonium (NH4+–N). Soil samples were taken from experiments at Efaw and Lake Carl Blackwell (LCB), Oklahoma, USA with ten treatments consisting of three N rates (50, 100, and 150 kg N ha−1) and three biochar rates (5, 10, and 15 t ha−1). Results at Efaw showed greater TSN and SOC under NBC compared to FN by 3 and 21%, respectively. No percentage difference was observed for NH4+–N while NO3−–N was lower by 7%. At LCB, TSN, SOC, NO3−–N, and NH4+–N were higher under NBC by 5, 18, 24, and 10%, respectively, compared to FN. Whereas application of biochar improved SOC at both sites, NO3−–N and NH4+–N were only significant at LCB site with a sandy loam soil but not at Efaw with silty clay loam. Therefore, biochar applied in combination with inorganic N can improve N availability with potential to increase crop N uptake on coarse textured soils.

Kinetic modelling of in situ treatment of petroleum hydrocarbon contaminated soil using bone char and NPK fertilizers

This study investigates the effectiveness of bone char (organic) and inorganic nitrogen, phosphorous, and potassium (NPK) fertilizers as stimulants in the degradability of petroleum hydrocarbon contaminants on soil. The physicochemical properties of the hydrocarbon sludge were used to assess the effectiveness of this process over an 8-week period using 0.5–3.5 kg mass of each fertilizer at different experiments. A first order kinetic model was used to estimate the rate of degradation of the total hydrocarbon content (THC) and total organic carbon (TOC) contaminants and the half-life of the remediation process. The microbial population within the period was also determined. The p-value (p < 0.05) indicated that these fertilizers were effective in degrading these contaminants on the soil, because of the significant difference between the treated and the control soil samples. A direct relationship was observed between with the mass and performance of the fertilizers. With 3.5 kg mass of the fertilizers, rate constants of 0.018 and 0.019 d− 1 were obtained for the removal of the THC and TOC contaminants, respectively, using the bone char fertilizer, whereas NPK fertilizer gave rates of 0.03 and 0.023 d− 1 respectively. The performance of the NPK fertilizer is attributable to its nitrogen and phosphorous content. The model adequately described the process and showed the effectiveness of both fertilizers in the remediation process.

Environmental fate and health exposures of the geogenic and anthropogenic contaminants in potable groundwater of Lower Ganga Basin, India

The study evaluated the sources and controlling factors of the groundwater contaminants in an agroeconomic region of Lower Ganga Basin using principal component analysis (PCA), multivariable linear regressions (MLR), correlation analysis, and hierarchical cluster analysis, and evaluated the public health risks using the Latin Hypercube Sampling, goodness-of-fit statistics, Monte Carlo simulation and Sobol sensitivity analysis based on the 1000 samples collected in two sampling cycles (N = 1000). The study reveals that the dissolution of fluoride-bearing minerals and semi-arid climate regulate the fluoride concentrations (0.10–18.25 mg/L) in groundwater. Extensive application of inorganic nitrogenous fertilizers and livestock manure mainly contributed to elevated nitrate levels (up to 435.0 mg/L) in groundwater. The health risks analysis indicates that fluoride exposure is more prevalent in the residents of each age group than the nitrate and both contaminants exhibited higher non-carcinogenic health risks on the infant and child (minor) age groups compared to adolescents and adults. Based on the cokriging interpolation mapping, the minor residents of 17.88%–23.15% of the total area (4545.0 km2) are vulnerable to methemoglobinemia whereas the residents of all age-groups in 38.47%–44.45% of the total area are susceptible to mild to severe dental/skeletal fluorosis owing to consumption of untreated nitrate and fluoride enriched groundwater. The Sobol sensitivity indices revealed contaminant levels, groundwater intake rate and their collective effects are the most influential factors to pose potential health risks on the residents. Artificial recharge and rainwater harvesting practices should be adopted to improve the groundwater quality and the residents are advised to drink purified groundwater.

Ammonia-oxidizing bacteria and fungal denitrifier diversity are associated with N2O production in tropical soils

Nitrous oxide (N2O) production in tropical soils cultivated with sugarcane is associated with ammonia-oxidizing bacteria (AOB) and fungal denitrifiers. However, the taxonomic identities and the community diversities, compositions, and structures of AOB and fungal denitrifiers in these soils are not known. Here, we examined the effects of applying different concentrations of an organic recycled residue (vinasse: regular non-concentrated or 5.8-fold concentrated) on the dynamics of AOB and fungal denitrifier community diversity and composition and greenhouse gas emissions during the sugarcane cycle in two different seasons, rainy and dry. DNA was extracted from soil samples collected at six timepoints to determine the dynamics of amoA-AOB and nirK-fungal community diversity and composition by amplicon sequencing with gene-specific primers. Bacterial and archaeal amoA, fungal and bacterial nirK, bacterial nirS and nosZ, total bacteria (16S rRNA) and total fungi (18S rRNA) were quantified by real-time PCR, and N2O and CO2 emissions were measured. The genes amoA-AOB and bacterial nirK clade II correlated with N2O emissions, followed by fungal nirK. The application of inorganic nitrogen fertilizer combined with organic residue, regardless of concentration, did not affect the diversity and structure of the AOB and fungal denitrifier communities but increased their abundances and N2O emissions. Nitrosospira sp. was the dominant AOB, while unclassified fungi were the dominant fungal denitrifiers. Furthermore, the community structures of AOB and fungal denitrifiers were affected by season, with dominance of uncultured Nitrosospira and unclassified fungi in the rainy season and the genera Nitrosospira and Chaetomium in the dry season. Nitrosospira, Chaetomium, Talaromyces purpureogenus, and Fusarium seemed to be the main genera governing N2O production in the studied tropical soils. These results highlight the importance of deciphering the main players in N2O production and demonstrate the impact of fertilization on soil microbial N functions.

Effects of biochar and N-stabilizers on greenhouse gas emissions from a subtropical pasture field applied with organic and inorganic nitrogen fertilizers

Pasturelands contribute significantly to the global CO2, CH4 and N2O emissions. These gas emissions are influenced by the amount and type of N-fertilizers applied and local climate. Recent studies showed potential of biochar and N-stabilizer compounds in minimizing CO2, CH4 and N2O emissions by regulating N-release from N-fertilizers. The present study was aimed at determining and comparing the effects of biochar and N-(n-butyl) thiophosphoric triamide + dicyandiamide (N-stabilizer) on CO2, N2O and CH4 emissions from a pasture fertilized with cattle manure or urea. The study was conducted during 2015 and 2016 in an established bermudagrass (Cynodon dactylon L. Pers.). Treatments consisted of combination of N-sources (manure, and urea) and two mitigation technologies [pine hardwood biochar (BC) and N-stabilizer] along with control. Emissions of GHGs were measured from each plot using static chamber systems. Both BC and N-stabilizer applications with manure applied to the hay field significantly decreased N2O emissions by 42% and 45%, respectively, in the year-2, and emission factors compared to manure only treatment. Addition of N-stabilizer to urea had significantly decreased N2O emissions compared to urea alone, while BC had statistically insignificant effect although numerically lowered N2O emissions in both the years. Application of manure to the soil resulted in significantly higher CO2 emissions in both years and CH4 emissions in 2016 compared to unfertilized soil. Urea application had significant effect on CO2 emissions in 2016, while no effect on CH4 emissions compared to control. Application of either biochar or N-stabilizer did not significantly affect CO2 and CH4 emissions.

Effect of Different Sulphur Rates, Organic and Inorganic Nitrogen Fertilizers on Pea Plants

Effect of Different Sulphur Rates, Organic and Inorganic Nitrogen Fertilizers on Pea Plants

Nutritive value of azolla as poultry feed-a review

Azolla has great prospective as poultry feed due to its high content of proteins, essential amino acids, vitamins (vitamin A, vitamin B12, a-Carotene), growth promoter intermediaries and minerals. Azolla contains (on DM basis) 20.4–28.5% crude protein, 2.37–6.70% ether extract,12.6–17.5% crude fibre, 15.7–19.9% total ash, 30.0–47.0% nitrogen free extract,48.2–54.8% neutral detergent fibre, 36.5–37.1% acid detergent fibre,0.80–2.22% calcium and 0.35–1.39% total phosphorous. It contains 9.10–26.2 ppm copper, 83.9–2418 ppm manganese, 30.0–225 ppm zinc, 283–1569 ppm iron and 206–632 ppm carotene. The total flavonoid and total phenolic contents (µg/ml) in methanolic extract are 56.2 and 87.3, respectively. It has good potential for imparting rich colour to egg yolk due to presence of a-carotene pigment. It has higher potential to proliferate without inorganic nitrogen fertilization and high rate of growth in water. Azolla on meal basis can be included in broiler ration and pullet chick ration up to a level of 5 and 10%, respectively without any adverse effect on their performance. Fresh azolla at a rate 200g/duck/day in White Pekin duck feeding was economical. Higher levels of inclusion of azolla limit its beneficial effect due to decrease in feed consumption owing to higher level of fibre comprising mostly of ADF and lignin in azolla. Azolla production through low cost technology can be popularised and supplemented in the diets chicken and ducks either in fresh or dried form for economic production of meat and egg.

Effects of Two Varieties and Fertilization Regimes on Growth, Fruit, and Silymarin Yield of Milk Thistle Crop

Milk thistle is an alternative crop to winter cereals for southern Europe as this species is drought tolerant and its fruits contain silymarin. The aim of this study was to assess the impact of two varieties and fertilization regimes (sheep manure and inorganic fertilizer) on crop productivity. A two-factor experiment was conducted in a randomized split-plot design with three replicates. The varieties were Palaionterveno and Spata, while the fertilization treatments were control, sheep manure, and calcium ammonium nitrate applied at 75 and 125 kg N ha−1. Variety and fertilization significantly affected plants development and productivity, as well as oil and silymarin yield. The use of manure and inorganic nitrogen fertilizer increased rosette diameter, oil and silymarin yield, above-ground biomass, and fruit yield. The influence of inorganic fertilization, regardless of the application dose, was more apparent than organic fertilization. Moreover, variety significantly affected plants growth and silymarin content, as well as silymarin composition. The variety Spata had the greatest silymarin content, reaching 4.40%, and a high silybin B concentration. In conclusion, the selection of a suitable variety is important for achieving high fruit and silymarin yields, while inorganic nitrogen fertilization can maximize the productivity of the milk thistle crop.

Water Quality Assessment of Some Fish Landing Sites of Beki River, of Barpeta, Assam, India

Water quality monitoring and assessment has become a critical issue because it affects human and aquatic life. In recent years Beki River of Assam, India have encountered serious threats which includes sand mining, use of fertilizers on the river banks, uncontrolled fishing that have altered the water quality of the river specially in the fish landing sites. These have caused significant reduction in abundance of the fresh water fishes in the region. This study identifies the parameters that are responsible for decreasing the water quality in the six fish landing sites of the river. The study shows low pH of the river water indicating its acidity nature. Decrease in Dissolved oxygen (DO) during the monsoon in Dumnigh at, Sapakama and Madulijar suggested poor quality of water indicating the slow rate of photosynthesis by phytoplankton present in the Beki River. The concentration of Iron in Gobardhana, Sapakama and Dumnigh at during post monsoon was higher than the maximum limit of 0.3 mg/l. Concentration of nitrate was found to be higher than the limit of 45 mg/l in all the landing sites except for Gobardhana due to application of inorganic nitrogen fertilizers in the agricultural farm in the river bank. Concentration of manganese, arsenic and lead was found to be higher than the maximum limit in the fish landing sites. The spatial variations of the major ions reflects the influence of various anthropogenic and lithology’s activities in the river system.

Transitions to Legume-Based Agrifood Systems – Stakeholders' Views from Hungary

The pressing need for the radical transformation towards more sustainable agricultural and food systems, which only recently gained substantially more acknowledgement, staged several underutilised crops in new roles. Legumes have become the primary focus of research and analytical attention first in agroecology, and lately in international policy communities and the social sciences. With their effortless talent to fix nitrogen into the soil, substitute animal protein, reduce greenhouse gas emissions, legumes are now recognised as forgotten stars, that could help both agriculture and the food industry become more ecological. However, legume production and consumption, albeit multiple advantages, remain still marginal in Europe for several reasons. This article adopts an interpretative policy framework to address the legume paradox, that is our legume-dependent agri-food systems relying on imports and simultaneously maintaining deficient production and consumption of legumes. We reviewed the state of the art of legume-based food systems in Hungary by analysing conceptual frameworks and data from exploratory mixed-method research. In a case study research, we analysed the root causes of this state-of-the-art through mapping the understanding of challenges and potentialities of legume value chains in Hungary by critical stakeholders. Our primary research question is what is at play behind and how Hungarian stakeholders make meaning of this paradox. We also explore how the current trends could still open pathways for more legumes in production and consumption. Drawing on insights from the literature and stakeholder interviews in Hungary, we show an extremely locked-in agri-food system. Our results indicate that especially small scale producers face difficulties to tackle with shallow yield stability of legumes. Their struggle is further aggravated by the dumping of cheap import of plant-based protein food and feed and inorganic nitrogen fertilisers, virtually absent small-scale processing, consumers' unawareness of legumes' benefits and preoccupation with their gut discomfort and food services' unwillingness to experiment with tasty plant-based protein food. We suggest several future research topics and pathways to promote more sustainable legume-based food systems. In conclusion, we argue that any transition towards legume-based food and feed systems would initially require the mutual engagement of multiple stakeholders in the value chains, strong policy support orchestrated by public institutions.

Nitrogen Mineralization, Soil Microbial Biomass and Extracellular Enzyme Activities Regulated by Long-Term N Fertilizer Inputs: A Comparison Study from Upland and Paddy Soils in a Red Soil Region of China

A long-term experiment (38 years) was conducted to elucidate the effects of long-term N addition on the net N mineralization in both paddy and upland soils, based on their initial soil N status, with and in connection with soil microbial biomass and N cycling extracellular enzyme activities. Two treatments without N addition CK (No fertilizer) and K (inorganic potassium fertilizer) and two treatments with N addition (inorganic nitrogen fertilizer) and NK (inorganic nitrogen and potassium fertilizer) were placed in incubation for 90 days. Results showed that the total N and soil organic carbon (SOC) contents were higher in the treatments with N application compared to the treatments without N in both paddy and upland soils. The SOC content of paddy soil was increased relative to upland soil by 56.2%, 45.7%, 61.1% and 62.2% without N (CK, K) and with N (N and NK) treatments, respectively. Site-wise, total N concentration in paddy soil was higher by 0.06, 0.10, 0.57 and 0.60 times under the CK, K, N and NK treatments, respectively, compared with upland soil. In paddy soil, soil microbial biomass nitrogen (SMBN) was higher by 39.6%, 2.77%, 29.5% and 31.4%, and microbial biomass carbon (SMBC) was higher by 11.8%, 11.9%, 10.1% and 12.3%, respectively, in CK, K, N and NK treatment, compared with upland soil. Overall, compared to upland soil, the activities of leucine-aminopeptidase (LAP) were increased by 31%, 18%, 20% and 11%, and those of N-acetyl-b-D-glucosaminidase (NAG) were increased by 70%, 21%, 13% and 18% by CK, K, N and NK treatments, respectively, in paddy soil. A significantly linear increase was found in the NO3−-N and NH4+-N concentrations during the 90 days of the incubation period in both soils. NK treatment showed the highest N mineralization potential (No) along with mineralization rate constant, k (NMR) at the end of the incubation. SMBC, SMBN, enzyme activities, NO3−-N and NH4+-N concentrations and the No showed a highly significant (p ≤ 0.05) positive correlation. We concluded that long-term N addition accelerated the net mineralization by increasing soil microbial activities under both soils.

Agricultural Management Affects the Active Rhizosphere Bacterial Community Composition and Nitrification.

ABSTRACTCropping system diversity provides yield benefits that may result from shifts in the composition of root-associated bacterial and fungal communities, which either enhance nutrient availability or limit nutrient loss. We investigated whether temporal diversity of annual cropping systems (four versus two crops in rotation) influences the composition and metabolic activities of root-associated microbial communities in maize at a developmental stage when the peak rate of nitrogen uptake occurs. We monitored total (DNA-based) and potentially active (RNA-based) bacterial communities and total (DNA-based) fungal communities in the soil, rhizosphere, and endosphere. Cropping system diversity strongly influenced the composition of the soil microbial communities, which influenced the recruitment of the resident microbial communities and, in particular, the potentially active rhizosphere and endosphere bacterial communities. The diversified cropping system rhizosphere recruited a more diverse bacterial community (species richness), even though there was little difference in soil species richness between the two cropping systems. In contrast, fungal species richness was greater in the conventional rhizosphere, which was enriched in fungal pathogens; the diversified rhizosphere, however, was enriched in Glomeromycetes. While cropping system influenced endosphere community composition, greater correspondence between DNA- and RNA-based profiles suggests a higher representation of active bacterial populations. Cropping system diversity influenced the composition of ammonia oxidizers, which coincided with diminished potential nitrification activity and gross nitrate production rates, particularly in the rhizosphere. The results of our study suggest that diversified cropping systems shift the composition of the rhizosphere’s active bacterial and total fungal communities, resulting in tighter coupling between plants and microbial processes that influence nitrogen acquisition and retention.IMPORTANCE Crops in simplified, low-diversity agroecosystems assimilate only a fraction of the inorganic nitrogen (N) fertilizer inputs. Much of this N fertilizer is lost to the environment as N oxides, which degrade water quality and contribute to climate change and loss of biodiversity. Ecologically inspired management may facilitate mutualistic interactions between plant roots and microbes to liberate nutrients when plants need them, while also decreasing nutrient loss and pathogen pressure. In this study, we investigate the effects of a conventional (2-year rotation, inorganic fertilization) and a diversified (4-year rotation, manure amendments) cropping system on the assembly of bacterial and fungal root-associated communities, at a maize developmental stage when nitrogen demand is beginning to increase. Our results indicate that agricultural management influences the recruitment of root-associated microbial communities and that diversified cropping systems have lower rates of nitrification (particularly in the rhizosphere), thereby reducing the potential for loss of nitrate from these systems.

Evaluation of organic and inorganic fertilizers on chemical and biochemical quality constituents of burley tobacco: Influence of fertilizers on chemical and biochemical quality of burley tobacco

A field experiment was conducted during 2011-13 at Burley Tobacco Research Centre, Kalavacharla, East Godavari district, Andhra Pradesh to study the effect of organic and inorganic manures viz., four formulations of organic manures (neem cake, pongamia cake, filter press cake, poultry manure, FYM and vermicompost in different ratios) and two levels of inorganic nitrogen fertilizers (120 and 160 kg N /ha) on chemical and biochemical quality constituents of burley tobacco. Cured leaf samples from bottom, middle and top leaf positions in different treatments were analysed for chemical and biochemical quality constituents. Total chlorophylls, carotenoids and nitrate nitrogen varied from 0.116 to 0.388, 0.161 to 0.531, 3.87 to 8.06 mg/g, respectively. Chlorophylls and carotenoids were higher in manure treatments compared to inorganic treatments. Polyphenols viz., chromogenic acid and rutin ranged from 0.58 to 3.89 mg/g and 0.94 to 2.85 mg/g respectively. Polyphenols were less with organic manures compared to inorganic manures. Proline content varied from 0.506 to 3.7 mg/g. Organic manures showed higher proline compared to inorganic Nitrogen. Chemical quality parameters viz., nicotine, reducing sugars and chlorides ranged from 0.4 to 1.73%, 0.49 to 1.93% and 0.39 to 2.84% respectively. Reducing sugars content is high with organic manure application compared to inorganic nutrients. Activity of soil enzymes is high with organic compared to inorganic manures. Manure treatments not only increased the content of carotenoids, proline, reducing sugars, chlorophyll, and free fatty acids which play an important role in the quality of tobacco but also decreased the levels of polyphenols and nitrate nitrogen, which are negatively correlated with the quality of tobacco. Among the different organic manures, manure A (neem cake, pongamia cake, filter press cake, poultry manure, FYM and vermicompost in the ratio of 2:2:2:2:1:1) showed superiority followed by Manure C (neem cake, pongamia cake, filter press cake, poultry manure, FYM and vermicompost in the ratio of 1.5:1.5:5:2:1:2) in their influence on chemical quality parameters of Burley tobacco.

Impact of inorganic nitrogenous fertilizers and farmyard manure combination on grain, straw, biological yield and harvest index of rice (Oryza sativa L.)

A pot culture experiment entitled “Impact of inorganic nitrogenous fertilizers and farmyard manure combination on grain, straw, biological yield and harvest index of rice (Oryza sativa L.). ” was conducted during kharif 2018-2019.on sandy loam soil. The experiment consisted of eight treatments viz. T1-Control, T2- 50% RDF, T3-50% RDF + FYM @ 5 t ha-1, T4-75% RDF, T5-75% RDF + FYM @ 5 t ha-1, T6- 100% RDF (NPK 80:40:40), T7-100% RDF + FYM @ 5 t ha-1 and T8-150% RDF. The experiment was laid out in a Randomized Block Design with three replications. The results revealed that highest and significant values were recorded with respect to growth parameters i.e., plant height, number of tillers per hill, effective tillers per hill and yield attributes i.e., number of panicles per hill, panicle length, number of filled grains 1000 seed weight (test weight) in the treatment that received 100% RDF + FYM @ 5 t ha-1. Combination of FYM (5 t ha-1) with lower levels of RDF (50 and 75% RDF) also registered higher increase in the above parameters as compared to the application of inorganic fertilizers alone with the corresponding levels. Grain and straw yields followed the same trend as that of growth parameters and at higher levels of nitrogen in the inorganic form(150 % RDF) the values of the various parameters including grain and straw yield were significantly lower than the treatment where 100% RDF +FYM @ 5 t ha-1was applied.

Effects of complementary and sole applications of inorganic fertilizers and winery solid waste compost on maize yield and soil health indices

The development of plant nutrition systems that enhance soil productivity through the use of mineral fertilizers combined with organic fertilizers has recently gained increased attention. Two field experiments were conducted in 2018 (from February to June) and 2018/19 (from December 2018 to April 2019) to assess the effects of complementary application of inorganic nitrogen (N) and phosphorus (P) fertilizers (INPF) and winery solid waste (WSW) composts on maize yield and soil health indicators. The INPF and optimum rates of microbially inoculated and uninoculated WSW compost types were combined at different ratios (0:0, 75:25, 50:50, 25:75 and 0:100 w/w) to supply proportionate N and P amount. The recommended INPF rates for maize (200 kg N ha-1 and 90 kg P ha-1) were mixed and included as a standard control. The interaction of compost type and application rate had no significant effects on total biomass yield (TBY), grain yield (GY) and harvest index (HI). The compost type had significant effects on GY and HI in 2018/19. The TBYs obtained from the 50:50, 75:25 and 100:0 compost-INPF combinations were significantly higher than that recorded from untreated control across the compost types in 2018. The 25:75 and 50:50 compost-INPF combinations gave GYs which were significantly higher than that obtained from the untreated control in 2018/19. In many instances, soil pH and the contents of organic C, NO3, P, K, Na and Zn recorded from treatments with the different mix ratios of compost and INPF were higher than that recorded from the untreated control. Grain yield correlated significantly and positively with the contents of soil NH4 (r = 0.59) and P (r = 0.53) indicating that these nutrients contributed to the final GY. In conclusion, the joint application of compost and INPF at 25:75 and 50:50 ratios appears promising for improving GY. Increase in soil K content suggested the need for a controlled application of WSW compost followed by frequent soil testing exercise to monitor and avoid unnecessary K build-up that may induce the deficiencies of other plant nutrients.

Soil potassium regulation by changes in potassium balance and iron and aluminum oxides in paddy soils subjected to long-term fertilization regimes

Southern China’s paddy soils are poor in potassium (K) and rich in iron (Fe) and aluminum (Al) oxides, both of which are affected by fertilizer application. However, the response of soil K budget to long-term K fertilization and Fe and Al oxides remains unclear, especially in the subsurface horizons in different soil types. Here, four long-term fertilization treatments (no fertilizer, CK; inorganic nitrogen and phosphorus fertilizers, NP; NPK; and the combined NPK and manure, NPKM) were selected to determine the effects of K input and different forms of Fe and Al oxides on soil K status at two soil layers (0–20, surface; and 20–40 cm, subsurface) in red (Ferralsols) and purple (Cambisols) paddy soils across China. Overall, treatments where K fertilizer application was withheld had lower surface soil exchangeable K (EK), non-exchangeable K (NEK), and total K contents than treatments applied with K fertilizer. In contrast, the treatment including K with manure fertilizer increased EK and NEK contents. Regardless of fertilization regimes, the contents of EK and NEK in both soil depths of purple soil were significantly higher than those in their corresponding depths of red soil. Moreover, there were significantly lower EK and NEK contents in the subsurface layer than those in the surface layer of red soil, while no significant differences were observed in purple soil. A positive correlation was obtained between K balances and soil EK contents (P < 0.05) and the slopes of linear regressions in red soil was higher than that in purple soil. A three-way ANOVA showed that the lone and interactive effects of experimental site, fertilization regime, and soil depth significantly influenced the contents of Fe and Al oxides in both soils. The application of NPKM can inhibit the decrease of free Fe and Al oxides in the surface layer of soil and increase the amorphous and chelated Fe and Al oxides, especially in red soil. Redundancy analysis showed that the amorphous Fe and Al oxides were the most important factors for regulating surface soil EK content. The free and chelated oxides were the most important factors for regulating NEK contents in red and purple soils, respectively, particularly in subsurface soil. Our results imply that the combined application of inorganic fertilizer and manure is a viable strategy for improving soil K availability by increasing K balance and regulating the contents and forms of Fe and Al oxides in different depths of paddy soil.