nitrogen levels
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2022 ◽  
Vol 13 (1) ◽  
pp. 223-230
Author(s):  
Idrissa Diédhiou ◽  
Pedro Pérez Martínez ◽  
Emmanuel Martínez Castro ◽  
Wilson Geobel Ceiro-Catasú

Maize is the most important crop in Mexico, being central to the diets of consumers, particularly smallholders, and an undetermined amount is allocated as straw, green fodder, and, to a lesser extent, as silage for animal feed. Nitrogen fertilizer is considered one of the most important factors affecting growth, grain yield, and maize biomass production. In this context, the main objective of this study was to evaluate the effects of different levels of nitrogen fertilizer on maize production. A randomized complete block experimental design consisted of three treatments of nitrogen (180, 160, and 80 kg/ha) with three replications and morphological (plant height, stem thickness, and rate of growth), yield, and yield components (cob weight, length, thickness, number of rows per cob, and plant biomass) variables were used. The results suggest that the increase in nitrogen levels increases all the parameters of maize production. However, at 160 kg/ha, the greatest production of fodder was recorded with 5.99 tons/ha, superior to the one reported at 180 kg/ha, which was 5.47 tons/ha. We conclude that the maize fodder production can be optimized with the use of 160 kg/ha in the conditions of the altiplano of San Luis Potosí (Mexico).


2022 ◽  
Vol 21 (1) ◽  
pp. 143-159
Author(s):  
K.M Alsaad

Fourty five local buffaloes naturally infected with A. marginal age of 2-5 years. Clinical signs, present parasireamia haematological and biochemical changes were studied. Thin thick blood smears Stained with Gimsas stain were used to identify the parasite. The results indicated that most of the infected were suffering from mild form of infection and the 1I11p01”l11I1E' clinical signs observed were mild rise of body temperature, increase respiratory and plus rate, weal: ruminal contraction and generalized weakness. Palcness and iteration of mucous membrane, loss appetite, nasal and ocular discharge, coughing, salivation, atarcp, constipation, diarrhea, and rccumbancy. Statistical analysis showc increase (P<0.01) in body temperature, respiratory and pulsera wlflc nigrrificant decrease (P<0.01) in ruminal contraction We. observed. Parasiteamia in infected animals ranged from 1.3- 5.2%. Values of red blood cell, haemoglobin and packed cell volume were significantly low (P<0.01). Total leulcocyric and neutrophils count was significantly increase (P<0.0l). and (P<0.05) respectively. Blood indices values showed a significant increase in (MCHC) (P<0.0l) while (MCV) values showed no difference, reticulocytes were also present mildly biochemical changes indicated higher levels of AST. Total bilirubin (P<0.01). Total protein concentration was less (P<0.01) and no difference was observed inALT and blood urea nitrogen levels between infected and control animals.


2022 ◽  
Vol 12 ◽  
Author(s):  
Mengzhen Li ◽  
Zehui He ◽  
Jiecong Yang ◽  
Qihua Guo ◽  
Heng Weng ◽  
...  

Background and Purpose: Coronavirus disease 2019 (COVID-19) rapidly resulted in a pandemic. Information on patients with a history of cerebrovascular disease (CVD) infected with severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) is limited. This study investigated the clinical features and the risk factors of developing adverse outcomes in patients with COVID-19 and with previous CVD.Methods: This was a single-center retrospective clinical study including all the confirmed cases of COVID-19 at Wuhan Huoshenshan Hospital from February 4 to April 7, 2020. Differences in clinical characteristics were compared between patients with and without a history of CVD. The incidences of severe events comprising all-cause death, intensive care unit admission, shock, and mechanical ventilation usage during hospitalization in two groups were compared using propensity score matching analysis and multivariate logistic regression analyses. Besides, the risk factors of developing severe events in patients with COVID-19 who also have history of CVD were analyzed.Results: A total of 2,554 consecutive patients were included in our study, of whom 109 (4.27%) had a medical history of CVD. Patients with CVD tend to be older and with more comorbidities, including hypertension, diabetes, coronary heart disease, and chronic obstructive pulmonary disease. The levels of white blood cell, neutrophil, C-reactive protein, creatine kinase isoenzymes, and lactate dehydrogenase were higher, whereas the levels of lymphocyte and albumin were lower in the CVD group. Compared to those without CVD, patients with CVD were more likely to have severe events after age matching (12.8 vs. 5.7%, P = 0.012). After adjusting for the confounding effects of age, sex, smoking, and comorbidities, the odds ratio for developing severe events with a history of CVD was 2.326 (95% CI, 1.168–4.630; P = 0.016). Besides, patients with CVD, either with decreased lymphocyte count (OR 9.192, 95% CI, 1.410–59.902, P = 0.020) or increased blood urea nitrogen (OR 5.916, 95% CI, 1.072–32.641, P = 0.041), had a higher risk of developing severe events during hospitalization.Conclusions: Patients with CVD history tend to have adverse clinical outcomes after being infected with SARS-COV-2. Decreased lymphocyte counts and increased blood urea nitrogen levels may be risk factors for adverse outcomes in patients with COVID-19, and had CVD.


2022 ◽  
Vol 52 (7) ◽  
Author(s):  
Pedro Paulo da Silva Barros ◽  
Peterson Ricardo Fiorio ◽  
José Alexandre de Melo Demattê ◽  
Juliano Araújo Martins ◽  
Zaqueu Fernando Montezano ◽  
...  

ABSTRACT: Sugarcane is a good source of renewable energy and helps reduce the emission of greenhouse gases. Nitrogen has a critical role in plant growth; therefore,estimating nitrogen levels is essential, and remote sensing can improve fertilizer management. This field study selects wavelengths from hyperspectral data on a sugarcane canopy to generate models for estimating leaf nitrogen concentrations. The study was carried out in the municipalities of Piracicaba, Jaú, and Santa Maria da Serra, state of São Paulo, in the 2013/2014 growing season. The experiments were carried out using a completely randomized block design with split plots (three sugarcane varieties per plot [variety SP 81-3250 was common to all plots] and four nitrogen concentrations [0, 50, 100, and 150 kgha-1] per subplot) and four repetitions. The wavelengths that best correlated with leaf nitrogen were selected usingsparse partial least square regression. The wavelength regionswere combinedby stepwise multiple linear regression. Spectral bands in the visible (700-705 nm), red-edge (710-720 nm), near-infrared (725, 925, 955, and 980 nm), and short-wave infrared (1355, 1420, 1595, 1600, 1605, and 1610 nm) regions were identified. The R² and RMSE of the model were 0.50 and 1.67 g.kg-1, respectively. The adjusted R² and RMSE of the models for Piracicaba, Jaú, and Santa Maria were 0.31 (unreliable) and 1.30 g.kg-1, 0.53 and 1.96 g.kg-1, and 0.54 and 1.46 g.kg-1, respectively. Our results showed that canopy hyperspectral reflectance can estimate leaf nitrogen concentrations and manage nitrogen application in sugarcane.


2021 ◽  
Vol 26 (6) ◽  
pp. 3031-3039
Author(s):  
MOHAMED MOSALEM ◽  
YASER MAZROU ◽  
SHIMAA BADAWY ◽  
MOHAMED ABD EL-RAHMAN ABD ULLAH ◽  
MOHAMED GHONEIM MUBARAK ◽  
...  

The present experiment was conducted at private farm during 2018/19 and 2019/20 seasons. The investigated area lies within the extremely arid belt, having long hot summer and short warm winter. The main goal of this investigation was to evaluate the effect of different sowing methods on yield components of wheat, using split plot design with three replications. Sowing methods in main plot were broadcasting method, row spacing 10, 15 and 20 cm apart). Nitrogen fertilizer levels in sub plot were 60, 75 and 90 kg N fed-1 (fed = 4200 m-2). The increase percentage due to row spacing at 20 cm apart (M4) compared to broadcasting method (M1) were (23.30 & 26.74%) for spike length; (5.11 & 6.94 %) for 1000 grain weight and (8.02 & 7.74%) for grain yield and according ally (3.07 & 3.08%) for harvest index in both seasons, respectively. Overall, from the present study the sowing method in rows with 20 cm apart and the optimum N fertilizer rate (90 kg fed-1) for durum wheat production in the soils of Qasir, Dakhala oasis on silt loam soil was the best treatment.


2021 ◽  
Vol 186 (2) ◽  
pp. 225-240
Author(s):  
Mazlum AYHAN ◽  
Ferhat KIZILGEÇİ ◽  
Muhammad Aamir IQBAL

Climate change, global warming, environmental pollution, greenhouse gas emissions from agricultural fields, stagnant wheat yields and reduced farm economic returns require optimisation of sources and doses of plant nutrients. A field study was conducted to evaluate wheat response to different forms of fertilisers and nitrogen (N) doses under Mediterranean conditions. The field trial was comprised of fertiliser sources, including chemical fertilisers, compost and leonardite, while different nitrogen levels (0, 80, 160, 240 kg ha-1) were also tested. The experimental variables included yield attributes (height of the, length of the spike, spikelets number per spike, thousand-grain weight and grain yield). In addition, nutritional quality attributes like protein and starch contents were studied along with NDVI values of wheat under different fertilisation regimes. The trial was executed using a randomised complete block (factorial) design using four replications. The results revealed that fertiliser forms and N doses remained ineffective for boosting yield attributes of wheat. For nutritional characteristics of wheat grains, a higher N dose remained instrumental in boosting protein, starch and wet gluten contents. Thus, 240 kg ha-1 of N dose might be recommended for general adoption under Mediterranean conditions; however, study findings are limited in scope and further in-depth studies are needed by testing organic manures from plant and animal origins.


Author(s):  
Jan E. Neuweiler ◽  
Johannes Trini ◽  
Hans Peter Maurer ◽  
Tobias Würschum

Abstract Key message The comparably low genotype-by-nitrogen level interaction suggests that selection in early generations can be done under high-input conditions followed by selection under different nitrogen levels to identify genotypes ideally suited for the target environment. Abstract Breeding high-yielding, nitrogen-efficient crops is of utmost importance to achieve greater agricultural sustainability. The aim of this study was to evaluate nitrogen use efficiency (NUE) of triticale, investigate long-term genetic trends and the genetic architecture, and develop strategies for NUE improvement by breeding. For this, we evaluated 450 different triticale genotypes under four nitrogen fertilization levels in multi-environment field trials for grain yield, protein content, starch content and derived indices. Analysis of temporal trends revealed that modern cultivars are better in exploiting the available nitrogen. Genome-wide association mapping revealed a complex genetic architecture with many small-effect QTL and a high level of pleiotropy for NUE-related traits, in line with phenotypic correlations. Furthermore, the effect of some QTL was dependent on the nitrogen fertilization level. High correlations of each trait between N levels and the rather low genotype-by-N-level interaction variance showed that generally the same genotypes perform well over different N levels. Nevertheless, the best performing genotype was always a different one. Thus, selection in early generations can be done under high nitrogen fertilizer conditions as these provide a stronger differentiation, but the final selection in later generations should be conducted with a nitrogen fertilization as in the target environment.


2021 ◽  
Vol 13 (4) ◽  
pp. 1372-1377
Author(s):  
Abinaya M. ◽  
R. Manivannan ◽  
M.V. Sriramachandrasekharan ◽  
P. Senthilvalavan ◽  
S. Kalaisudarson ◽  
...  

Nitrogen and boron are necessary for the metabolic activities of rice for its growth. With this perspective, a field experiment was conducted in farmer’s field during 2020 at Kuttalam, Mayladuthurai district, Tamilnadu in sandy clay loam(Padugai Series – TypicUstifluvents) to predict the response of rice (Oryza sativa) to different levels of nitrogen(N) and boron (B) application. The treatments consisted of Factor A- Nitrogen levels, 0, 75, 150, 225 kg ha-1 and Factor B- Boron levels 0, 1.5, 3.0 kg ha-1. Fifteen treatments were conducted in a Factorial randomised block (FRBD) design with three replications.  The test crop was rice with a variety ADT 46.    Concerning nitrogen alone, the highest grain (5344 kg ha-1) and straw yield was recorded in N3(225 kg ha-1). Among the boron levels tested, the highest grain (4695 kg ha-1) and straw yield (6509 kg ha-1) was registered in B1 (1.5 kg ha-1) in rice. The highest total nutrient uptake viz., N(88.2 kg ha-1), P(30.5 kg ha-1), K(105.0 kg ha-1) and B(172mg kg-1)  were recorded in N3B1. Among the N alone, the highest total nutrient uptake viz., N(78.1kg ha-1, P(26.3kg ha-1), K (95.8 kg ha-1) and B(156.6 mg kg-1) in N3. Concerning B alone, the highest nutrient uptake viz., N(60.5, kg ha-1) , P(17.8kg ha-1) K(74.9 kg ha-1) and B(112.1mg kg-1) were registered in B1 over other B levels. The highest grain (5631 kg ha-1) was recorded in N3B1 (225 kg N ha-1 and 1.5kg B ha-1) than other interactions. The study concluded that applying nitrogen and boron is required to achieve the maximum yield of rice in sandy clay loam soil.


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