Organic Nitrogen Sources Research Articles

Saffron spice quality in response to integrated nutrient management under lesser Himalayan conditions of Rawalakot Azad Jammu & Kashmir

Integrated nutrient management is an environment friendly approach of plant nutrition being used for crop productivity and improvement in soil quality on sustainable basis. A three-year multi-location experiment was conducted to estimate the spice quality of saffron subjected to the integration of organic and inorganic nitrogen sources. At each location, the experiment was laid out in randomized complete block design. The treatments were T1 = control (without organic/inorganic N source/amendment); T2 = Full recommended nitrogen (i.e. urea fertilizer @ equivalent to 100 kg N ha−1; UN100); T3 = Poultry manure (PM) @ equivalent to 100 kg total N ha−1 (i.e. PM100); T4 = Farm yard manure (FYM) @ equivalent to 100 kg total N ha−1 (i.e. FYM100); T5 = PM50+FYM50; T6 = UN75 + PM25; T7 = UN50 + PM50; T8 = UN25 + PM75; T9 = UN75 + FYM25; T10 = UN50 + FYM50; T11 = UN25 + FYM75 and T12 = UN50 + PM25+ FYM25. Among treatments, poultry manure (100%) and urea nitrogen with poultry manure (UN50 + PM50) significantly affected the quality attributes of saffron. On the other hand, among sites, the crocin, picrocrocin and saffranal contents were in order of Khaigala (23.81% crocin, 20.01% picrocrocin and 0.27% saffranal) >Trarkhel (19.04% crocin, 16.99% picrocrocin and 0.25% saffranal) and > Abbaspur (17.80% crocin, 15.45% picrocrocin and 0.23% saffranal). Similarly, among years, the crocin, picrocrocin and saffranal contents were significantly higher in the third year compared to the first and second year. In conclusion, the integration of organic nitrogen sources with inorganic nitrogen has the potential to improve saffron quality.

Bioleaching rare earth elements from coal fly ash by Aspergillus niger

Rare earth elements (REEs) are abundant in certain mining coal, and further enriched in coal fly ash (CFA) after coal combustion. If the appropriate leaching technology is chosen, the CFA can be used as an unconventional source of REEs. In this paper, culture conditions and bioleaching process of Aspergillus niger (A. niger) were optimized, the mechanism of acid production and factors of the bioleaching process of A. niger were discussed, and the bioleaching mechanism of REEs from CFA by A. niger was expounded. The results showed that organic nitrogen sources affected the morphology and acid production capacity of A. niger, and the A. niger used in this study mainly secreted oxalic acid (4.05 mg/L). Secondly, the initial pH value, the most influential factor, further affected the bioleaching process by affecting the acid production of A. niger. Therefore, by optimizing the initial pH value to enhance the acid production capacity of A. niger and developing the best bioleaching system, the CFA can reach a leaching rate of 30.91 % for total REEs. Finally, based on the test results of organic acids and pH, combined with previous studies, we speculated the main mechanism of REES bioleaching from CFA by A. niger as proton exchange and organic ligand complexation. Microbial leaching (e.g., A. niger) integrates economic, environmental, and resource use values.

Abundance and sources of organic nitrogen in fine (PM2.5) and coarse (PM2.5–10) particulate matter in urban Hong Kong

Organic nitrogen (ON) in atmospheric particles is much less monitored compared to inorganic nitrogen (IN), despite its significant contribution to atmospheric N deposition budget. In this study, we expanded a newly developed instrumental method for IN and ON in PM2.5 samples to PM10 samples. We determined the quantities of ON and IN for paired PM2.5 and PM10 samples collected at an urban coastal site in Hong Kong, southern China over a year. These measurements also allowed the determination of IN and ON abundance in the coarse PM (i.e., PM2.5–10) by taking the difference between PM10 and PM2.5. The measurement results show that ON accounted for 27.6 % and 21.1 % of total N in fine and coarse particles, respectively, and was mainly (87.7 %) distributed in the fine mode at the site. The seasonal variation of ON/total N was relatively small in PM2.5 (23.6–30.4 %) while considerably larger in coarse PM (4.3–42.1 %). Analysis aided by concurrently measured source indicators revealed that sea spray, biological particle emissions, and dust mixed with anthropogenic pollutants are potentially significant sources of ON in coarse particles. Positive matrix factorization (PMF) source apportionment further revealed that industrial emissions/coal combustion (43.6 %), soil dust emission (16.3 %), fresh sea salt emission (15.2 %), and aged sea salt (24.9 %) are major sources of PMcoarse-bound ON at the site. The contributions of industrial emissions/coal combustion and soil dust emission to ON were significantly higher in autumn and winter. Fresh sea salt emissions contributed greater proportions to ON in spring and summer, while ON associated with the aged sea salt source was higher in spring and autumn. These findings have advanced our quantitative understanding of the sources of PMcoarse-bound ON, which was scarcely determined in the past. Furthermore, the ON measurement data in fine and coarse particles helps estimate ON deposition, which has been previously under-evaluated.

Canopy structure and understorey light availability in Nothofagus and podocarp-broadleaf stands in a New Zealand forest

ABSTRACT The ability of some ectomycorrhizal fungi to access organic sources of nitrogen is known to influence decomposition, nitrogen mineralisation and soil carbon storage. The consequences for aboveground ecosystem structure and processes are less well-documented. We used the LAI-2200C Plant Canopy Analyzer to compare leaf area index and understorey light availability of ectomycorrhizal Nothofagus stands and arbuscular mycorrhizal podocarp-broadleaf stands growing on similar soils at a dry forest site in the Wairarapa district of New Zealand’s North Island. N. solandri was the sole overstorey tree in the three Nothofagus stands, and the ericaceous shrub Leucopogon fasciculatus was prominent in the understorey. The three podocarp-broadleaf stands were more diverse and more varied, the major contributors to basal area being Elaeocarpus dentatus, Hedycarya arborea, Cyathea dealbata, Carpodetus serratus and Dacrydium cupressinum. Leaf area index of Nothofagus stands averaged one unit lower (4.04) than that of neighbouring podocarp-broadleaf stands (5.11). Average light availability under Nothofagus stands (3.6–4.9%) was twice that beneath podocarp-broadleaf stands (1.6–2.1%). The lower leaf area index, greater light transmittance, and monodominance of Nothofagus stands probably reflects suppression of arbuscular mycorrhizal species by ectomycorrhizal short-circuiting of the nitrogen cycle. This study expands the evidence of positive feedback mechanisms stabilising ectomycorrhizal dominance in some forests.

Influence of Organic Nitrogen Sources on Aromatic Rice (Oryza sativa L.) Cultivation in the Eastern Plateau and Hill Region of India

The field experiment was conducted at farm of Divyayan Krishi Vigyan Kendra, Ramakrishna Mission Ashrama, Ranchi, Jharkhand, India during kharif season of 2021 following the three times replicated randomized block design with 7 organic N sources (control, 100% FYM, 100% vermicompost (VC), 100% Karanj cake (KC), 50% FYM +50% VC, 50% VC +50% KC, 50% FYM +50% KC) to study the response of transplanted aromatic rice to various organic N sources. The results expressed that N applied through manures ensured higher plant response over control and specifically, that through 50% VC +50% KC recorded the maximum plant height, tillers/m2 and leaves/plant. Further, this combined application of VC and KC also recorded maximum productive tillers/m2 (199.3), panicle length (24.1 cm), filled grains/panicle (172.8), test weight (22.9 g), grain yield (7.37 t/ha), straw yield (9.08 t/ha) and harvest index (44.8%) resulting in higher gross return (₹4,83,590/ha), net return (₹3,37,079/ha) and B:C (3.30). 100% N applied through KC remained as the second-best alternative in ensuring high growth, yield and profitability in aromatic rice.

Development of a green fermentation strategy with resource cycle for the docosahexaenoic acid production by Schizochytrium sp.

The fermentation production of docosahexaenoic acid (DHA) is an industrial process with huge consumption of freshwater resource and nutrient, such as carbon sources and nitrogen sources. In this study, seawater and fermentation wastewater were introduced into the fermentation production of DHA, which could solve the problem of fermentation industry competing with humans for freshwater. In addition, a green fermentation strategy with pH control using waste ammonia, NaOH and citric acid as well as FW recycling was proposed. It could provide a stable external environment for cell growth and lipid synthesis while alleviating the dependence on organic nitrogen sources of Schizochytrium sp. It was proved that this strategy has good industrialization potential for DHA production, and the biomass, lipid and DHA yield reached to 195.8 g/L, 74.4 g/L and 46.4 g/L in 50 L bioreactor, respectively. This study provides a green and economic bioprocess technology for DHA production by Schizochytrium sp.

Free fatty acids in sunflower oil soap stock progressed the sophorolipid production by Candida catenulata

AbstractSophorolipids are a group of surface‐active glycolipid compounds that can be synthesized by several yeasts, especially the Candida genera. Soap stock is a by‐product of vegetable oils refinery that enriches mono‐unsaturated fatty acids, and its application is interesting as a low‐cost industrial residue in sophorolipid production. In this study, the sophorolipid production was evaluated by Candida catenulate KP324968, using sunflower oil soap stock and glucose as the hydrophobic and hydrophilic carbon sources, respectively. The results indicated the ratio of hydrophobic to a hydrophilic carbon source, initial pH, and type of nitrogen source had significant roles in the performance of the cells. The highest specific biomass growth rate was about 0.0447 ± 0.0013 h−1 and a sophorolipid production rate of 49.96 ± 0.33 mg L−1 h−1 was obtained at a soap stock‐to‐glucose ratio of 1, initial pH of 5.5, and temperature of 30°C. The addition of organic nitrogen sources such as yeast extract and urea obtained a higher sophorolipid production in comparison with ammonium nitrate and potassium nitrate as the mineral nitrogen sources. Usage of both yeast extract and urea increased the sophorolipid production rate by 4.4% and 6.9%, in comparison with separate usage of yeast extract and urea, respectively. The characterization of the sophorolipid confirmed an emulsification index of about 30 ± 2.9% for diesel‐in‐water and 50 ± 3.5% for sunflower oil‐in‐water systems. The critical micelle concentration was determined at 280 mg L−1. The produced sophorolipid at a concentration of 500 mg L−1 showed an antibacterial capacity about of 95.4 ± 1.1%, and 44.7 ± 0.8% against Bacillus subtilis (Gram‐positive) and Escherichia coli (Gram‐negative) bacteria, respectively.

Responses of Worowo [Senecio biafrae (Oliv. & Hiern.) S. Moore] to Composts enriched with Organic Nitrogen Sources

Worowo (Senecio biafrae) is a semi-wild, indigenous and nutritious vegetable. Demand for worowo vegetable is increasing due to its nutritional values, thus necessitating its domestication for increased production. However, there is limited information on soil fertility requirements of worowo and the use of inorganic fertilizers could be expensive and detrimental to environment. Composts, on the other hand are environment-friendly and effective, but their use is constrained by low nitrogen contents, thereby necessitating enrichment with various nitrogen sources. Responses of worowo to organically enriched composts were therefore investigated. Composted Cattle Dung+Sawdust (CDS) and Poultry Droppings+Sawdust (PDS), at 1:1 (w/w) were enriched to 60 g N/ kg with meals from dried bone-BnM, blood-BM, hoof-HM, and horn-HnM, neem-NM and Tithonia leaves-TM. Compost treatments obtained were: CDS and PDS (no enrichment added), CDSBnM, CDSBM, CDSHM, CDSHnM, CDSNM and CDSTM; PDSBnM, PDSBM, PDSHM, PDSHnM, PDSNM and PDSTM. Worowo was raised in pots with CDS, PDS and 60 g N/kg enriched composts at 30 t/ha and control (soil alone), compared with 60 kg N/ha NPK 15-15-15 in a completely randomized design with three replicates. Data generated from the growth indices and edible Shoot Yield (ESY) of worowo (t/ ha), which were measured at 60, 120 and 180 Days After Planting (DAP) were analyzed using ANOVA at α0.05. ¬¬¬¬¬¬The ESY (t/ha) of 60 g N/kg CDSNM (54.93) was significantly higher than NPK (36.53) and others but similar to CDS (50.93) while pots treated with PDS were lowest (8.00). The CDSDNM at 60 g N/kg applied at 30 t/ha could hence be adopted for worowo production.

Effect of Mineral and Organic Nitrogen Sources on Vegetative Development, Nutrition, and Yield of Sugarcane

Although sugarcane yield is directly influenced by the availability of nitrogen (N), the efficiency of mineral N (MN) fertilization is considered to be low due to nitrate leaching and ammonia volatilization. Thus, the search for alternative sources of N that are cheaper and more consistent with sustainable farming practices has been stimulated. As chicken litter is an organic waste with the potential to supply N to major crops, we tested the hypothesis that the use of this litter as a source of organic N (ON) is as efficient as the application of MN (ammonium nitrate) in promoting the growth, nutrition, and yield of sugarcane plants grown during both plant cane and ratoon cane seasons. Experiments were conducted in a 5 × 5 × 2 subdivided plot scheme in the growing area of the Denusa Mill, Destilaria Nova União S/A, located in the midwest region of Brazil, with treatments consisting of five doses each of MN (0, 40, 80, 120, and 160 kg ha−1) and ON (0, 2, 4, 6, and 8 T ha−1), evaluated in two crop seasons (plant cane-2019/2020 and ratoon cane-2020/2021). The application of different doses of MN or ON influenced the height and number of tillers of sugar cane plants, and the application of ON, supplied by chicken litter, to this crop was as efficient as that of MN in promoting plant growth. MN and ON also increased the leaf content of N, P, and K; moreover, the absence of one source of nitrogen was compensated by the other. ON application (up to 4.8 T ha−1) also increased sugarcane yield in addition to promoting growth. Furthermore, this study highlighted the superior quality of the regrowth observed in the IACSP95-5094 cultivar, which manifested in increased tillering and stem diameter, resulting in consistently higher yields in the ratoon crop.

Assessment of Soil Physico-chemical Properties in Direct Seeded Rice and Succeeding Lentil Crop under Integrated Nitrogen and Weed Management Practices in Eastern Uttar Pradesh, India

An experimentation was conducted during 2019-20 and 2020-21 at Banaras Hindu University, Varanasi, to evaluate the direct and residual effect of organic sources of nitrogen and weed management practices on various soil physico-chemical properties. The experiment was laid out in split plot arrangement having four nitrogen management treatments in main plot viz., Control (only P and K), RDF (150-60-60 kg ha-1 N-P2O5-K2O), 75% RDN (Inorganic) + 25% through FYM, 75% RDN (Inorganic) + 25% through Vermicompost and five weed management practices in subplots which consisted of Wheat residue as mulch (4 t ha-1) fb bispyribac Na 25 g a.i. ha-1 (2-4 leaf stage of weed), Pendimethalin 1 kg a.i. ha-1fb bispyribac Na 25 g a.i. ha-1 (2-4 leaf stage of weed), Sesbenia up to 30 days (Brown manuring), Two hand weeding (20 and 40 DAS) and Weedy check and replicated thrice. Results indicated that application of 25% nitrogen through farmyard manure in combination with 75% nitrogen through urea being at par with 75% RDN (Inorganic) + 25% through Vermicompost, brought significant improvement in soil chemical properties (electrical conductivity and pH) but physical property i.e., Bulk density did not turn significant after harvest of direct seeded rice. The treatment also recorded significantly maximum available soil nitrogen, phosphorus and potassium compared to 100% nitrogen through urea and control treatment though remained comparable with 25% nitrogen through vermicompost along with 75% nitrogen through urea during both years. Whereas, in respect to the residual effect of organic sources, improvement in soil properties after harvest of succeeding residual lentil crop was observed, but failed to touch the level of significance in either year of study. Among weed management practices, maximum improvement in soil physicochemical properties was noticed with the use of Sesbania brown manuring for both years after harvest of rice as well as after harvest of succeeding lentil crop but the differences could not reach up to the level of significance.

Green Forage Productivity, Crude Protein Yield, Seed Yield and Production Economics of Dual Purpose Ricebean (Vigna umbellata) as Influenced by Different Organic Sources of Nitrogen

A field experiment was conducted at Central Research Farm, Gayeshpur, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, West Bengal, India during kharif (June–September, 2019 and 2020) to evaluate the influence of different organic nitrogen sources on growth, quality, yield and yield parameters and production economics of dual purpose ricebean (Vigna umbellata) of Bidhan ricebean-2 variety. The experiment was laid out in Randomized Block Design (RBD) with three replications. The organic nitrogen sources used in the experiment were vermicompost, farm yard manure and biocompost. Experiment results revealed that application of 50% RDN through FYM+50% RDN through Vermicompost gave significantly higher leaf–stem ratio and drymatter accumulation. Among other treatments, with application of 50% RDN through FYM+50% RDN through vermicompost significantly highest green forage yield, dry matter yield was observed. Highest seed yield and yield attributes like pods plant-1, seeds pod-1 was observed with application 50% RDN through FYM+50% RDN through vermicompost. Application of 50% RDN through FYM+50% RDN through Vermicompost recorded highest quality parameters like crude protein, crude fat, crude fibre and crude protein yield when compared to other treatments. With respect to economics of different organic and inorganic nitrogen sources, application of 50% RDN through FYM+50% RDN through vermicompost recorded higher gross returns and net returns but higher B-C ratio was noticed with application of 100% RDN through inorganic fertilizers.

Nitrogen metabolism in mycobacteria: the key genes and targeted antimicrobials.

Nitrogen metabolism is an important physiological process that affects the survival and virulence of Mycobacterium tuberculosis. M. tuberculosis's utilization of nitrogen in the environment and its adaptation to the harsh environment of acid and low oxygen in macrophages are closely related to nitrogen metabolism. In addition, the dormancy state and drug resistance of M. tuberculosis are closely related to nitrogen metabolism. Although nitrogen metabolism is so important, limited research was performed on nitrogen metabolism as compared with carbon metabolism. M. tuberculosis can use a variety of inorganic or organic nitrogen sources, including ammonium salts, nitrate, glutamine, asparagine, etc. In these metabolic pathways, some enzymes encoded by key genes, such as GlnA1, AnsP2, etc, play important regulatory roles in the pathogenesis of TB. Although various small molecule inhibitors and drugs have been developed for different nitrogen metabolism processes, however, long-term validation is needed before their practical application. Most importantly, with the emergence of multidrug-resistant strains, eradication, and control of M. tuberculosis will still be very challenging.

Construction and function of a high-efficient synthetic bacterial consortium to degrade aromatic VOCs

Aromatic volatile organic compounds (VOCs) are a type of common pollution form in chemical contaminated sites. In this study, seven aromatic VOCs such as benzene, toluene, ethylbenzene, chlorobenzene, m-xylene, p-chlorotoluene and p-chlorotrifluorotoluene were used as the only carbon source, and four strains of highly efficient degrading bacteria were screened from the soil of chemical contaminated sites, then the synthetic bacterial consortium was constructed after mixing with an existing functional strain (Bacillus benzoevorans) preserved in the laboratory. After that, the synthetic bacterial consortium was used to explore the degradation effect of simulated aromatic VOCs polluted wastewater. The results showed that the functional bacterium could metabolize with aromatic VOCs as the only carbon source and energy. Meanwhile, the growth of the synthetic bacterial consortium increased with the additional carbon resources and the alternative of organic nitrogen source. Ultimately, the applicability of the synthetic bacterial consortium in organic contaminated sites was explored through the study of broad-spectrum activity.

Medium composition and aeration to high (R,R)-2,3-butanediol and acetoin production by Paenibacillus polymyxa in fed-batch mode.

Concerning the potential application of the optically active isomer (R,R)-2,3-butanediol, and its production by a non-pathogenic bacterium Paenibacillus polymyxa ATCC 842, the present study evaluated the use of a commercial crude yeast extract Nucel®, as an organic nitrogen and vitamin source, at different medium composition and two airflows (0.2 or 0.5 vvm). The medium formulated (M4) with crude yeast extract carried out with the airflow of 0.2 vvm (experiment R6) allowed for a reduction in the cultivation time and kept the dissolved oxygen values at low levels until the total glucose consumption. Thus, the experiment R6 led to a fermentation yield of 41% superior when compared to the standard medium (experiment R1), which was conducted at airflow of 0.5 vvm. The maximum specific growth rate at R6 (0.42h-1) was lower than R1 (0.60h-1), however, the final cell concentration was not affected. Moreover, this condition (medium formulated-M4 and low airflow-0.2 vvm) was a great alternative to produce (R,R)-2,3-BD at fed-batch mode, resulting in 30g.L-1 of the isomer at 24h of cultivation, representing the main product in the broth (77%) and with a fermentation yield of 80%. These results showed that both medium composition and oxygen supply have an important role to produce 2,3-BD by P. polymyxa.

Synergistic impacts of climate change and human activities on spatiotemporal organic nitrogen burial variation in a plateau lake in southwest China

ABSTRACT The concentration and sources of organic nitrogen (ON) in lake sediments affect lake nitrogen cycles. However, the factors influencing ON accumulation rate (ONAR) are unclear. We collected 3 sediment cores from northern, eastern, and southern Dianchi Lake (DC-N, DC-E, and DC-S, respectively) in July 2014, to study the effects of autochthonous and allochthonous sources of ON. The ON and ONAR increased 2.4–5.1 and 2.6–4.8 times, respectively, from 1900 to 2000, especially since the 1980s, when algal blooms have occurred more frequently. The ON decreased in the order DC-S > DC-N > DC-E, whereas the ONAR decreased in the order DC-N > DC-S > DC-E, suggesting that ONAR was influenced by ON content as well as the depositional environment. The total concentrations of n-alkanes (n-C12 to n-C34) ranged from 4719 to 61 960 ng g−1 in the 3 sediment cores, with proportions varying with vertical depth. The sources of ON were mainly allochthonous (soil erosion and terrestrial plants) and autochthonous (algal and aquatic plants) in DC-S and DC-N, respectively, and primarily mixed planktonic and terrestrial in DC-E. The stochastic impacts by regression on population, affluence, and technology (STIRPAT) model revealed that a 1% increase in air temperature and nitrogen fertilizer corresponded to an increase in ONAR by 23–33% and 20–79% in the Dianchi Lake basin, especially in DC-S and DC-E. However, a 1% increase in urban land area reduced ONAR by 2–11%, especially in DC-N. Our study suggests that the spatial and temporal ONAR in Dianchi Lake may increase in response to a warmer and wetter climate combined with increasing chemical nitrogen fertilizer application.

Effects of organic and inorganic nitrogen sources on the transcriptome of gellan gum biosynthesis by Sphingomonas paucimobilis.

Investigate the effects of different nitrogen sources on the metabolic characteristics of Sphingomonas paucimobilis during gellan gum (GG) production was helpful for developing optimized conditions that are widely applicable to all GG production processes. We compared the effects of organic nitrogen (ON) and inorganic nitrogen (IN) sources during GG production using transcriptome sequencing. Our results showed that compared with the IN source, the ON source effectively improved the cell number and GG production of S. paucimobilis during fermentation. There were significant differences in gene transcription levels between the ON and IN groups at different fermentation times. The transcriptional levels of multiple genes in the pathways from α-D-glucose-1P to glyceraldehyde-3P were reduced in the ON group, whereas those of multiple genes in the pathways from glyceraldehyde-3P to acetyl-CoA were significantly enhanced in the ON group after 12 h of fermentation. The transcription levels of multiple genes participating in the citrate cycle and upstream of fatty acid metabolism pathways were significantly enhanced in the ON group after 12 h of fermentation. Except for the transcripts per million (TPMs) of pgm and rfbA genes in ON, which were significantly higher than those in IN at 12 h after fermentation, the TPMs of the majority of genes in ON were significantly lower than those in IN. The transcription levels of genes participating in the transformation of N-acetyl-D-glucosamine (GlcNAc) to UDP-N-acetyl-alpha-D-glucosamine (UDP-GlcNAc) were enhanced in the ON group during the fermentation process.

A Paradigm Shift towards Beneficial Microbes Enhancing the Efficiency of Organic and Inorganic Nitrogen Sources for a Sustainable Environment

The use of beneficial microbes as biofertilizer has become fundamental in the agricultural sector for their potential role in food safety and sustainable crop production. A field trial was conducted to study the influence of beneficial microbes on the efficiency of organic and inorganic sources. The experiment was conducted in two consecutive years (2008–2009 and 2009–2010) in a farmer’s field at Dargai Malakand Division. A randomized complete block design was used with four replications. The results revealed a significantly higher straw and grain nitrogen concentrations for the treatments receiving 50% N from urea + 50% N from FYM + BM, followed by the treatments receiving 50% N from urea + 50% N from (FYM + PM) + BM and 120 kg N ha−1 from urea fertilizer, respectively. Comparing the relevant treatments with and without BM, an increasing trend in N concentrations in straw and grain was observed with BM. The results revealed the highest grain total nitrogen, straw total nitrogen and total nitrogen uptake by wheat crop for the treatments receiving 120 kg N ha−1 from urea, followed by the treatments receiving 50% N from urea + 50% N from PM + BM and 50% N from urea + 50% N from (FYM + PM) + BM. Moreover, after comparing the relevant treatments with and without BM, for the parameters mentioned, an increasing trend in nitrogen uptake was observed. Significantly higher total soil nitrogen was obtained for treatment with 50% N from urea + 50% N from FYM + BM, followed by the treatment with 50% N from urea + 50% N from (FYM + PM) + BM or 50% N from urea + 50% N from PM + BM, respectively, as compared to the control treatment plot. Markedly higher soil mineral nitrogen was obtained for the 50% N from urea + 50% N from (FYM + PM) + BM treatment, followed by the treatment with 50% N from urea + 50% N from FYM + BM and 50% N treatment from urea + 50% N from PM + BM, compared to the control treatment. Comparing the relevant treatments with and without BM, an increasing trend in total soil N (g kg−1 soil) and soil mineral N (mg kg−1 soil) was noted with BM application. From the results, a significant increase in soil organic matter status (g kg−1 soil) due to application of organic and inorganic fertilization was summarized. Significantly higher soil organic matter (g kg−1 soil) was recorded for the treatment receiving 50% N from urea + 50% N from FYM + BM compared to untreated control plots. Our study further revealed an increasing trend in soil organic matter status (g kg−1 soil) when comparing the relevant treatments with and without BM.

Impact of humic acid with organic and inorganic nitrogen sources on growth and yield traits of maize (Zea mays L.)

Impact of humic acid with organic and inorganic nitrogen sources on growth and yield traits of maize (Zea mays L.)

Deciphering of Microbes × Nitrogen source fertilizers Interaction for improving nitrogen use efficiency in spring maize

In this study the influence of combined use of organic and inorganic nitrogen (N) sources along with the beneficial micro-organisms on grain N uptake, N use efficiency and N utilization efficiency in maize was evaluated. Organic fertilizer (FYM) and inorganic N source (synthetic fertilizer) was applied in ratio viz. (0:100, 25:75, 50:50, 75:25 and 100:0) with and without beneficial micro-organism. Different levels viz. 100, 150 and 200 kg ha−1 of N was used to accelerate the efficiency of N. Results showed that combination of FYM and inorganic N (50:5) along with the application of beneficial micro-organism significantly increased the total N uptake, N utilization efficiency, highest stover grain and grain protein. However, maximum N uptake and protein contents were recorded with application of 150 kg N ha−1. Application of N (100 kg ha−1) gave the highest N-use efficiency and N utilization efficiency. In conclusion, N application level of 100 kg N ha−1, beneficial micro-organism and 50:50 ratio of inorganic and organic N was proved better in enhancing N-use efficiency and grain quality of maize.

15N tracing reveals preference for different nitrogen forms of Fusarium oxysporum f. sp. cubense tropical race 4.

Plant uptake of nitrogen is often associated with increased incidence of banana Fusarium wilt, a disease caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4). However, the nitrogen metabolic preferences of Foc TR4 pathogens remain unknown. In this study, we investigated the ecophysiological patterns of Foc TR4 grown on different combinations of organic and inorganic nitrogen. Potato Dextrose Agar (PDA) and Rose Bengal Medium (RBM) were used as an organic nitrogen source, which was sequentially replaced with inorganic N (0, 50% or 90%) in the form 15NH4NO3 or NH4 15NO3 to reveal preferential assimilation of ammonium or nitrate. The results showed that mycelium biomass and nitrogen content decreased significantly, while the carbon content and C:N ratio increased in Foc TR4 grown on media containing inorganic nitrogen sources. Mycelium biomass was negatively correlated with C:N ratio. Mycelium 15N abundance increased significantly between the PDA50 + A50/RBM50 + A50 treatments (50% organic nitrogen+50%15NH4NO3) and the PDA10 + A90/RBM10 + A90 treatments (10% organic nitrogen+90%15NH4NO3). These results indicate that the higher C:N ratio reduced mycelium growth by reducing its biomass and diameter and showed that Foc TR4 preferred to use ammonium nitrogen to promote the growth. These findings suggest that treating banana crops with a combination of organic and inorganic (i.e., nitrate) nitrogen could be a better way to defend against Fusarium wilt of banana.