Effects Of Different Fertilizers Research Articles

Effect of Different Fertilizer and Silicon Levels on Grain Quality of Maize (Zea mays L.)

A field experiment with spilt plot design was conducted to study the ‘effect of fertility and silicon levels on the nutritional quality of maize’ during Kharif 2022 and 2023 at Rajasthan College of Agriculture (RCA), MPUAT, Udaipur, Rajasthan, India. The main plot treatments consist of four levels of Compounded NPK fertilizer (F0: Control, F50: 50% RDF, F75: 75% RDF and F100: 100 % RDF) and the sub-plot treatments consist of four levels of soil application of Diatomaceous Earth (Si0, Si100, Si200 and Si300). Pratap Makka-9 of maize variety was used for research purpose. The protein content, protein yield, carbohydrate and energy in maize grain were higher under 100% RDF than other levels of fertilizer. Application of 300 kg Diatomaceous Earth per hectare recorded higher protein content, protein yield, carbohydrate and energy in maize grain over the rest of silicon levels. The crude fat in maize grain was lower in 100% RDF. Application of 300 kg Diatomaceous Earth per hectare recorded lower crude fat in maize grain. Significantly higher protein yield was recorded under the combined application of 100% RDF and 300 kg diatomaceous earth per hectare. However, protein yield was at par in the application of 75% RDF with 300 kg Diatomaceous Earth per hectare and 100% RDF with 200 kg Diatomaceous Earth per hectare. The lowest crude fat was recorded under the combined application of 100% RDF and 300 kg Diatomaceous Earth per hectare over the rest of treatment combinations. Application of 100% RDF with 300 kg DE ha-1 (F100Si300) was recommended treatment for nutritional high quality maize grain.

The Crop Phosphorus Uptake, Use Efficiency, and Budget under Long-Term Manure and Fertilizer Application in a Rice–Wheat Planting System

Little is known about the effect of the long-term application of organic and inorganic fertilizers on P-use efficiency, P budget, and the residual effect of P fertilizer. To clarify the effect of different fertilization on soil P balance in a rice (Oryza sativa L.)–wheat (Triticum aestivum L.) rotation system is helpful to promote the sustainable development of agriculture. Thus, a thirty-five-year fertilizer experiment was conducted with eight treatments, including an unfertilized control (CK); chemical nitrogen (N), phosphorus (P), and potassium (K) fertilizers; and organic manure (M) either alone or in combination treatments (N, NP, NPK, M, MN, MNP, and MNPK). The results indicated that crop yields and P uptake were higher in the combined application of manure and chemical fertilizer treatments than in the manure or chemical fertilizer alone treatments. Soil P budget indicated a 23.4–55.4 kg P ha−1 yr−1 surplus in the organic combined with or without mineral fertilizer treatments, but the soil P budget indicated a 20.0 and 21.9 kg P ha−1 yr−1 deficit in the control and N treatments. The proportion of residual fertilizer P converted to soil available P in NP, NPK, M, MN, MNP, and MNPK treatments was 4.5%, 4.8%, 19.1%, 19.0%, 11.5%, and 13.3%, respectively, over a 35-year period. Furthermore, according to the higher P content and crop uptake in organic manure treatment compared with chemical P fertilizer alone, an organic addition could effectively reduce the use of chemical fertilizer and become an effective way of sustainable development in practice. Therefore, the combined application of organic and inorganic fertilizer will be a practical method to increase crop yields and soil P status in a rice–wheat planting system.

Effect of Different Fertilizer Types on Quality of Foxtail Millet under Low Nitrogen Conditions.

In order to clarify the effect of different fertilizers on foxtail millet quality under low nitrogen conditions, we used JGNo.21 and LZGNo.2 as experimental materials and set up five treatments, including non-fertilization, nitrogen, phosphorus, compound, and organic fertilizers, to study the regulation of different fertilizer types on agronomic traits, nutrient fractions, and pasting characteristics of foxtail millet under low nitrogen conditions. Compared with the control, all of the fertilizers improved the agronomic traits of JGNo.21 to a certain extent. Nitrogen and compound fertilizer treatments reduced the starch content of JGNo.21; the starch content was reduced by 0.55% and 0.07% under nitrogen and compound fertilizers treatments. Phosphorus and organic fertilizers increased starch content, and starch content increased by 0.50% and 0.56% under phosphorus and organic fertilizer treatments. The effect of each fertilizer treatment on protein content was completely opposite to that of starch; different fertilizer treatments reduced the fat content of JGNo.21 and increased the fiber content. Among them, nitrogen and phosphorus fertilizers increased the yellow pigment content; the yellow pigment content increased by 1.21% and 2.64% under nitrogen and phosphorus fertilizer treatments. Organic and compound fertilizers reduced the content of yellow pigment; the yellow pigment content was reduced by 3.36% and 2.79% under organic and compound fertilizer treatments. Nitrogen and organic fertilizers increased the fat content of LZGNo.2; the fat content increased by 2.62% and 1.98% under nitrogen, organic fertilizer treatment. Compound and phosphorus fertilizer decreased the fat content; the fat content decreased by 2.16% and 2.90% under compound and phosphorus fertilizer treatment. Different fertilizer treatments reduced the cellulose and yellow pigment content of LZGNo.2. The content of essential, non-essential, and total amino acids of JGNo.21 was increased under compound and nitrogen fertilizer treatments and decreased under organic and phosphorus fertilizer treatments. The content of essential, non-essential, and total amino acids of LZGNo.2 was significantly higher under compound, nitrogen, and organic fertilizer treatments compared with control and significantly decreased under phosphorus fertilizer treatments. Nitrogen and compound fertilizer treatments significantly reduced the values of peak viscosity, trough viscosity, breakdown viscosity, final viscosity, setback viscosity, and pasting time of each index of JGNo.21; phosphorus and organic fertilizer treatments improved the values of each index. In contrast, the pasting viscosity of LZGNo.2 increased under phosphorus fertilizer treatment and decreased under nitrogen fertilizer treatment. Reasonable fertilization can improve the quality of foxtail millet, which provides a scientific theoretical basis for improving the quality of foxtail millet.

Divergent impacts of fertilization regimes on below-ground prokaryotic and eukaryotic communities in the Tibetan Plateau

Chemical nutrient amendment by human activities can lead to environmental impacts contributing to global biodiversity loss. However, the comprehensive understanding of how below- and above-ground biodiversity shifts under fertilization regimes in natural ecosystems remains elusive. Here, we conducted a seven-year field experiment (2011–2017) and examined the effects of different fertilization on plant biodiversity and soil belowground (prokaryotic and eukaryotic) communities in the alpine meadow of the Tibetan Plateau, based on data collected in 2017. Our results indicate that nitrogen addition promoted total plant biomass but reduced the plant species richness. Conversely, phosphorus enrichment did not promote plant biomass and exhibited an unimodal pattern with plant richness. In the belowground realm, distinct responses of soil prokaryotic and eukaryotic communities were observed under fertilizer application. Specifically, soil prokaryotic diversity decreased with nitrogen enrichment, correlating with shifts in soil pH. Similarly, soil eukaryotic diversity decreased with increased phosphorous inputs, aligning with the equilibrium between soil available and total phosphorus. We also established connections between these soil organism communities with above-ground plant richness and biomass. Overall, our study contributes to a better understanding of the sustainable impacts of human-induced nutrient enrichment on the natural environment. Future research should delve deeper into the long-term effects of fertilization on soil health and ecosystem functioning, aiming to achieve a balance between agricultural productivity and environmental conservation.

Effects of different nutrient inputs in organic parsley cultivation

ABSTRACT Parsley (Petroselinum crispum Mill.) can play a key role in healthy nutrition for people. This study evaluated the effects of different fertilisers on parsley grown in organic greenhouse conditions in the Samsun province of Turkey. Three organic fertilisers (liquids based on compost, nettles and wood ash) were tested and compared with chemical fertiliser and a control with no fertiliser. The results showed that application of wood ash solution significantly increased EC and concentrations of P and K in the soil, compared with the no fertiliser control. The nettle extract and the compost solution had the most prominent effects on concentrations of nutrients in the parsley leaf tissue. The highest total yields were obtained in the treatments with nettle extract (8.95 kg m−2) and wood ash solution (8.71 kg m−2), which were similar to the yield in the treatment with chemical fertiliser (8.48 kg m−2). The present results suggested that nettle extract and wood ash solution provided effective fertilisers to achieve high yields and quality in organic parsley cultivation. Further studies were recommended to test combinations of nettle extract and wood ash solutions in different proportions for edible leafy species.

Dune soil nitrogen leaching for Chinese-yam cultivation: Impact of microbe-decomposable slow-release fertilizer

Chinese yam production is thriving in Aomori Prefecture, a cold and snowy region in Japan. Recently, there has been an increasing risk of nitrogen leaching in Chinese-yam fields, which consist of sandy soil, due to localized torrential rain. The relationships between the type of fertilizer used for Chinese-yam cultivation, the amount of nitrogen (N) leaching, and the timing of leaching remain unknown. Therefore, this study aimed to fill this knowledge gap by investigating the effects of different fertilizers (fast-acting and/or slow-release fertilizer) and irrigation practices (conventional and/or excessive irrigation) in order to mitigate the detrimental impact of nitrogen leaching on groundwater quality. An enhanced mathematical model and the spatiotemporal dynamics of inorganic nitrogen concentration in soil pore water were evaluated the negative impact of nitrogen leaching on the groundwater environment was evaluated. The results showed that the combined use of slow-release fertilizers could significantly reduce nitrate-nitrogen concentration in soil-water, especially during the harvest season. This study demonstrated that cultivating Chinese yam with a fertilizer application system that includes the use of slow-release fertilizer can diminish the negative impact of nitrogen leaching on the groundwater environment, contributing to our understanding of sustainable agricultural practices in regions facing similar environmental challenges. Therefore, our findings represent an important advancement providing new approaches to maintaining productivity while mitigating the adverse impacts on groundwater environments, as well as offering guidelines for agricultural practices in regions facing similar environmental challenges.

The Influence of Chemical Fertilizers on the Effectiveness of Biochar in Mitigating Cadmium Mobility in Soil

The focus of this study was to explore how various fertilizers influence the movement of cadmium in soil treated with biochar. The research utilized a strong acid sandy loam soil from Chanthaburi Province, naturally rich in organic matter with moderate cation exchange capacity and low nitrogen, potassium, phosphorus, sulfate, salinity and chloride levels. The soil was purposely contaminated with 50 mg kg-1 of cadmium and treated with biochar derived from water hyacinth through pyrolysis at 450°C for an hour. This biochar displayed moderate alkalinity, high organic matter, phosphorus, potassium, and cation exchange capacity, but low nitrogen content. Analytical techniques like Scanning Electron Microscopy and Fourier-Transform Infrared Spectroscopy were employed to study the surface characteristics of the biochar. The cadmium adding soil was blended with 10% biochar and various chemical fertilizers at a 0.04% ratio. Diethylenetriamine pentaacetate (DTPA) extraction was used to assess the bioavailability of cadmium to plants in the soil, while sequential extraction was conducted to identify the different forms of cadmium present in the soil. The study revealed distinct effects of different fertilizers on cadmium mobility. Fertilizers like 46-0-0 and 0-3-0 caused a transformation of cadmium from stable to less stable forms, increasing the bioavailability of cadmium to plants. Conversely, fertilizers such as 15-15-15, 0-0-50, 0-0-60, and 0-52-34 shifted cadmium from less stable to more stable forms, resulting in decreased cadmium extracted by DTPA. Other fertilizers showed no significant impact on cadmium mobility in the soil. A stepwise linear regression analysis highlighted that nitrogen content, potassium content, and electrical conductivity were influential factors affecting cadmium mobility.

Influence of Organic and Inorganic Fertilizers on Tea Growth and Quality and Soil Properties of Tea Orchards' Top Rhizosphere Soil.

Organic-based fertilizers have been ratified to be effective in ameliorating tea growth and the fertility of soil. However, the effect of integrated fertilization on tea growth and quality and the chemical properties of the soil in tea gardens are unclear. To address this, from 2020 to 2021, five different treatments were carried out in the greenhouse of the Tea Research Institute, Hangzhou, CAAS, including CK (control), NPK (chemical fertilizers), RC (rapeseed cake), NPK+B (chemical fertilizer + biochar), and NPK+RC, to investigate the effects of different fertilizations on soil chemistry and tea growth and quality. The results indicated that NPK+B and NPK+RC significantly improved the different amino acid and catechin concentrations in the young shoots, stems, and roots of the tea compared to the CK. The plant growth parameters, e.g., the plant height, no. of leaves, mid-stem girth, and fresh weights of stems and leaves, were significantly increased with integrated fertilization (NPK+B and NPK+RC) compared to the CK and solo organic and inorganic fertilizers. The chlorophyll contents (Chl a, Chl b, and Chl a+b) were generally higher with NPK+RC than with the CK (37%, 35%, and 36%), RC (14%, 26%, and 18%), and NPK (9%, 13%, and 11%) treatments. Integrated fertilization buffered the acidic soil of the tea garden and decreased the soil C:N ratio. NPK+RC also significantly increased the soil's total C (31% and 16%), N (43% and 31%), P (65% and 40%), available P (31% and 58%), K (70% and 25%), nitrate (504% and 188%), and ammonium (267% and 146%) concentrations compared to the CK and RC. The soil macro- (Mg and Ca) and micronutrients (Mn, Fe, Zn, and Cu) were significantly improved by the RC (100% and 72%) (49%, 161%, 112%, and 40%) and NPK+RC (88% and 48%) (47%, 75%, 45%, and 14%) compared to the CK. The chlorophyll contents and soil macro- and micronutrients were all significantly positively correlated with tea quality (amino acids and catechin contents) and growth. These results indicated that integrated fertilization improved the soil nutrient status, which is associated with the improvement of tea growth and quality. Thus, integrated nutrient management is a feasible tool for improving tea growth, quality, and low nutrient levels in the soil.

Effect of different fertilizers on the growth of duckweed (Lemna minor) as aquatic plant resources utilization in sustaining Red Tilapia (Oreochromis niloticus) culture

Duckweed (Lemna minor) is one of the smallest floating aquatic plants in the world. This plant is potentially important in the aquaculture feed industry since aquaculture feed is the major operational cost in fish production. This 37-days study was done to see the effect of different fertilizers; (goat manure, chicken manure and organic fertilizer) at the same concentration of 2g/L on duckweed growth. Tap water without fertilizer was used as a control. Water parameters such as pH, temperature, nitrate, phosphate, and ammonia were observed. The result of duckweed growth rate after 37 days in goat manure fertilizer (0.76 grams/day) is the highest followed by chicken manure fertilizer (0.15 grams/day), organic fertilizer (0.02977 grams/day) and the control (-0.00 133 grams/day). The number of the duckweed at the end of experiment by using the goat manure fertilizer is higher which is 489 units, followed by chicken manure fertilizer (179 units), organic fertilizer (64 units) and control (22 unit). Treatment of goat manure fertilizer has a high concentration of nitrate 1.99 ppm, ammonia 2.69 ppm and available phosphate 7.71 ppm which suitability for duckweed growth. Since duckweed is easy to be cultured, this natural resource of aquatic plants can be produced commercially for Red Tilapia ( Oreochromis niloticus) farm.

Effect of different fertilizers and no-till versus strip-till on silage maize yield in a dual cropping system

Effect of different fertilizers and no-till versus strip-till on silage maize yield in a dual cropping system

INFLUENCE OF DIFFERENT NUTRIENT SOURCES AND GENOTYPES ON THE CHEMICAL QUALITY AND YIELD OF LETTUCE

<p>The aim of this study was to examine the effect of different fertilizers on the yield and antioxidant capacity of two lettuce genotypes “Santoro RZ” and “Kiribati RZ”.</p> <p>Lettuce genotypes are fertilized with organic fertilizer (Slavol) and organic-inorganic NPK fertilizer (Fitofert hemisuper plus ) during the vegetation. The analyzed parameters were root length and head weight of lettuce, total phenols, and flavonoids, as well as antioxidant capacity. Lettuce genotypes “Santoro RZ” and “Kiribati RZ” fertilized with organic fertilization showed the highest content of total phenols (358.13 ± 1.30 mg RU/100 g of fresh sample), the total content of flavonoids (114.22 ± 0.3 mg RE/100 g of fresh sample) and antioxidant capacity (neutralization of DPHH radicals 58.72 ± 1.88%).</p> <p>The results revealed that the yield and antioxidant capacity of lettuce can be improved by using organic fertilizers.</p>

Waste-Derived Fertilizer Acts as Biostimulant, Boosting Tomato Quality and Aroma

Tomato quality is intricately regulated by a combination of factors, including the presence of bioactive compounds referred to as secondary metabolites and various organoleptic characteristics. These attributes are notably influenced and harmonized by the specific growing conditions, with a particular emphasis on the type of fertilization employed. Traditionally, chemical fertilizers have been favored in crop cultivation due to their cost-effectiveness and ability to accelerate crop growth. However, in pursuit of sustainable and intelligent agricultural practices, there is a growing need for alternative fertilizers. In this context, the present study aimed to assess the impact of fertilizers derived from waste materials, specifically sulfur bentonite and orange residue (referred to as SB), on tomato quality. This assessment extended to examining qualitative and quantitative alterations in aroma-related volatile compounds and the antioxidant systems of tomatoes, in comparison to the conventional use of fertilizers such as horse manure (HM) and nitrogen, phosphorus, and potassium (NPK). The results obtained revealed distinct effects of different fertilizers on tomato quality. Notably, parameters such as TPRO (total protein), TCARB (total carbohydrate), LIC (lycopene content), TCAR (total carotenoid content), total phenols (TPHE), total flavonoids (TFLA), and aroma profiling exhibited significantly superior values in the group treated with sulfur bentonite (SB) fertilizer. These findings strongly suggest that the novel fertilizer functioned as a biostimulant, enhancing the nutraceutical and sensory attributes of tomatoes, with a pronounced impact on the synthesis of secondary metabolites and the aroma profile of the fruits.

Use of anaerobic digestate as biofertilizer: Another step forward in the valorisation of the invasive brown macroalgae Rugulopteryx okamurae

The rapid and aggressive colonization of the invasive macroalgae Rugulopteryx okamurae on the southern coast of Spain has caused an unprecedented environmental, health and economic impact. At present, the scientific community has focused on the valorisation of R. okamurae waste, as tonnes of collected biomass from this species end up in landfills. In this sense, the aim of this study was to assess, for the first time, the viability of the R. okamurae digestate as biofertilizer to growth the Mediterranean forage species Avena strigosa (black oat). Two anaerobic digestates, derived from the anaerobic digestion of the thermally pre-treated (120 °C; 45 min) and the zeolite-assisted mechanically pre-treated invasive macroalgae, were used in this study. Both digestates were compared with a commercial inorganic nutritive solution. The effect of different fertilizers and water availability on forage height, aerial, root and seed biomass, as well as photosynthetic activity and macro- and micronutrient forage content were studied. The control treatment showed the lowest height at the end of the experiment (0.38 m) and the digestate from the thermally pre-treated macroalgae treatment had the highest one (0.59 m). Final fresh and dry aerial biomass was separately significantly dependent on both fertilizer type and water stress. Final root and seed biomass were not significantly different among the treatments studied. The lowest photosynthetic activity was obtained from the control treatment (3.61 µmol m⁻² s⁻¹), while the highest was reached by the digestate where R. okamurae was thermally pre-treated (4.96 µmol m⁻² s⁻¹). The results of this study show that both digestates tested can be used effectively as organic fertilizer in the cultivation of black oats, obtaining production efficiency values similar (digestate from mechanically pre-treated macroalgae) or higher (digestate from thermally pre-treated macroalgae) than inorganic fertilizer.

Response of nutrient supplementation through INM on yield and quality parameters of pomegranate (Punica granatum)

A study was carried out during 2020–21 and 2021–22 at the research farm of Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana to investigate efficacy of different fertilizers on yield, yield attributing characters and biochemical parameter on pomegranate (Punica granatum L.) cv. Bhagwa. Different doses of RDF 50%, 75%, 100% FYM, biofertilizers were evaluated against control by following randomized complete block design, 22 treatments with 3 replications. The results revealed that yield parameters, viz. fruit weight (260.83 g), aril weight (168.00 g), rind weight (92.83g), rind thickness (3.63 mm), fruit length (6.64 cm) and fruit diameter width (4.82 cm), number of fruits per tree (105.61), yield (27.55 kg/tree), fruit firmness (28.76 lb/inch2), fruit cracking (26.17%), fruit set (42.30%), fruit retention (76.19%), fruit drop (23.81%); and biochemical parameters, viz. juice content (35.23%), TSS (14.15 °Brix), acidity (0.82%) and TSS acid ratio (17.37), total sugar (12.06%), reducing sugar (9.86%), non- reducing sugar (2.31%), sugar: acid ratio (41.00) ascorbic acid (16.79 mg/100 g) and anthocyanin content (4.94 mg/100 g) were significantly affected by different organic amendments and biofertilizers treatment against control. Treatment T21-100% RDF + FYM + Azotobacter + PSB proved most effective in enhancing yield attributing characters and biochemical parameters of pomegranate. This treatment gave best result by increasing the nutritional status of the plant through the beneficial effects of different fertilizers.

"Effects of Different Fertilizers on the Yield and Yield Attributing Parameters of Sweet Potato (Ipomoea Batatas L.) in the Eastern Midhill of Nepal"

"Effects of Different Fertilizers on the Yield and Yield Attributing Parameters of Sweet Potato (Ipomoea Batatas L.) in the Eastern Midhill of Nepal"

Fertilizers Containing Balanced Proportions of NH4+-N and NO3−-N Enhance Maize (Zea mays L.) Yield Due to Improved Nitrogen Recovery Efficiency

The current study aimed to improve the nitrogen recovery efficiency (NRE) of maize under the application of balanced proportions of ammoniacal-nitrogen (NH4+-N) and nitrate-nitrogen (NO3−-N) (1:1), as well as to determine economic impacts of such fertilizers on maize productivity. A 3-year field study was carried out in Sahiwal, Punjab, Pakistan during the 2018–2020 growing seasons with autumn maize. In parallel, multi-location field experiments were conducted at farmer’s fields in Sahiwal during the same growing seasons with autumn maize. The trials compared the effects of different fertilizers like urea, calcium ammonium nitrate (CAN), Sarsabz nitrophos (NP), nitrphos plus (NP Plus), and di-ammonium phosphate (DAP) on maize growth and yield, as well their economic efficiency. The results revealed that the application of Sarsabz NP and CAN increased the maize grain yield by 30%, 13%, 15%, 19%, 15%, and 9% as compared to the control, NP + urea, NP Plus + CAN, NP Plus + urea, DAP + urea, and DAP + CAN, respectively. In addition, the combined application of NP and CAN increased the total N and NO3−-N concentrations, whereas it decreased the NH4+-N concentrations in the soils. By contrast, NP + CAN increased the NH4+-N concentrations in maize leaves as compared to NO3−-N concentrations. Overall, the NRE of maize plants and the net return were higher under combined application of NP and CAN. In conclusion, CAN fertilizer increased the soil NO3−-N concentrations, which thus assimilated in the plants as NH4+ and improved the NRE of maize. Improved NRE thus enhanced maize yield and resulted in the maximum net return as compared to all other fertilizer combinations.

Individual and synergistic effects of different fertilizers and gibberellin on growth and morphology of chili seedlings

Gibberellins (GA3), as well as the basic elements phosphorus (P), nitrogen (N), and potassium (K), are crucial to the growth of chili. This study investigates the effect of different fertilizers and plant growth regulator on the growth and morphology of chili seedlings. Soil application of NPK, urea, SOP, and DAP (2.5 g/L) was applied during sowing, and N in two splits at sowing and after twenty days of sowing while foliar application of GA3 (50 mg/L) was applied after fifteen days of germination. The result of five seedlings' traits plant height (PH), plant girth (PG), plant spread (PS), number of leaves (NOF), and root length (RL) demonstrated a significant difference among growth-related traits in chili seedlings owing to the use of fertilizers, GA3, and their combinations. An optimum level of K and P alone or in combination with GA3 had a significant effect on all traits. PH was particularly influenced by the combination of GA3 with K and P whereas other traits like PG, NOF, PS, and RL are greatly influenced by the application of NPK, urea, SOP, DAP, and their combination with GA3. The study results showed an increase in chili seedlings' growth and morphology in response to various fertilizers and GA3.

Exploring antibiotic resistance load in paddy-upland rotation fields amended with commercial organic and chemical/slow release fertilizer.

Agricultural fertilization caused the dissemination of antibiotic resistance genes (ARGs) in agro-ecological environment, which poses a global threat to crop-food safety and human health. However, few studies are known about the influence of different agricultural fertilization modes on antibiotic resistome in the paddy-upland rotation soils. Therefore, we conducted a field experiment to compare the effect of different fertilization (chemical fertilizer, slow release fertilizer and commercial organic fertilizer replacement at various rates) on soil antibiotic resistome in paddy-upland rotation fields. Results revealed that a total of 100 ARG subtypes and 9 mobile genetic elements (MGEs) occurred in paddy-upland rotation soil, among which MDR-ARGs, MLSB-ARGs and tet-ARGs were the dominant resistance determinants. Long-term agricultural fertilization remarkably facilitated the vertical accumulation of ARGs, in particular that bla ampC and tetO in relative abundance showed significant enrichment with increasing depth. It's worth noting that slow release fertilizer significantly increased soil ARGs, when comparable to manure with 20% replacing amount, but chemical fertilizer had only slight impact on soil ARGs. Fertilization modes affected soil microbial communities, mainly concentrated in the surface layer, while the proportion of Proteobacteria with the highest abundance decreased gradually with increasing depth. Furthermore, microbial community and MGEs were further proved to be essential factors in regulating the variability of ARGs of different fertilization modes by structural equation model, and had strong direct influence (λ = 0.61, p < 0.05; λ = 0. 55, p < 0.01). The results provided scientific guidance for reducing the spreading risk of ARGs and control ARG dissemination in agricultural fertilization.

Improvement of soil fertility and rice yield after long-term application of cow manure combined with inorganic fertilizers

Fertilization is an effective technique to improve soil fertility and increase crop yield. The long-term effects of different fertilizers on soil considerably vary. Over 38 consecutive years of different fertilization positioning experiments in a double cropping rice field of Qiyang Red Soil Experimental Station, seven different fertilization treatments including CK (no fertilization), NPK (nitrogen, phosphorus, and potassium fertilizer), M (cow manure), NPKM (nitrogen, phosphorus, and potassium with cow manure), NPM (nitrogen and phosphorus with cow manure), NKM (nitrogen and potassium with cow manure), and PKM (phosphorus and potassium with cow manure) were applied to study the effects on rice yield, soil fertility, and nutrient apparent balance in a paddy field. The results showed that the annual average yields of rice in NPKM, NPM, NKM, PKM, M, NPK and CK treatments ranged from 6 214 to 11 562 kg ha–1. Yields under long-term organic and inorganic treatments (NPKM, NPM, NKM and PKM) were 22.58, 15.35, 10.53 and 4.41%, respectively, greater than under the NPK treatment. Soil organic carbon (SOC), total nitrogen (TN), available nitrogen (AN) and available potassium (AK) concentration with long-term organic and inorganic treatment (NPKM, NPM, NKM and PKM) were significantly higher than in inorganic fertilizer (NPK) treatments. Soil total phosphorus (TP) and available phosphorus (AP) contentration with organic fertilizer combined with inorganic N and P fertilizer treatment (NPKM, NPM and PKM) were significantly higher than with inorganic fertilizer alone (NPK treatments). The average annual rice yield (11 562 kg ha–1), SOC (20.88 g kg–1), TN (2.30 g kg–1), TP (0.95 g kg–1), TK (22.50 g kg–1) and AP (38.94 mg kg–1) concentrations were the highest in the NPKM treatment. The soil AN concentration (152.40 mg kg–1) and AK contentration (151.00 mg kg–1) were the highest in the NKM treatment. N and P application led to a surplus of nitrogen and phosphorus in the soil, but NPKM treatment effectively reduced the surplus compared with other treatments. Soils under all treatments were deficient in potassium. Correlation analysis showed that SOC, TN, AN, TP, and AP contentration was significantly correlated with rice yield; the correlation coefficients were 0.428, 0.496, 0.518, 0.501, and 0.438, respectively. This study showed that the combined application of N, P, and K with cow manure had important effects on rice yield and soil fertility, but balanced application of N, P, and K with cow manure was required.

Effects of Different Fertilizers on Soil Microbial Diversity during Long-Term Fertilization of a Corn Field in Shanghai, China

The long-term applications of different fertilizers (chicken manure, swine manure, and organic fertilizer) on the microorganisms of a corn field were investigated. The microbial communities during four periods (seedling, three-leaf, filling and mature periods) were comprehensively studied with molecular biology technology. Results showed that most nutrient contents (organic matter, nitrogen, phosphorus, and potassium) and levels of several heavy metals (As, Pb, and Cr) in the chicken and swine manures were higher than those in the organic fertilizer. The alpha diversity varied during the long-term fertilization, and the chicken manure was the best fertilizer to maintain the abundance of microorganisms. The microbial community of soil changes over time, regardless of the addition of different fertilizers. The correlations between environmental factors and microbial communities revealed that nutrient substances (available nitrogen, available potassium, and NO3-N) were the most significant characteristics with the chicken and swine manures, while organic matter and nitrogen exhibited similar effects on the microbial structure with the organic fertilizer. The Pearson correlations of environmental factors on genus were significantly different in the organic fertilizer tests compared with the others, and Pseudomonas, Methyloligellaceae, Flavobacterium, and Bacillus showed significant correlations with the organic matter. This study will provide a theoretical basis for improving land productivity and sustainable development in corn fields.