scholarly journals Urochloa ruziziensis responses to sources and doses of urea

2016 ◽  
Vol 20 (5) ◽  
pp. 401-407 ◽  
Author(s):  
João E. S. Lima ◽  
Adriano S. Nascente ◽  
Wilson M. Leandro ◽  
Pedro M. da Silveira
Keyword(s):  
Chlorophyll Content ◽  
Dry Matter ◽  
N Fertilization ◽  
N Losses ◽  
Total N ◽  
Rainy Period ◽  
N Sources ◽  
Use Efficiency ◽  
Tiller Density ◽  
Relative Chlorophyll Content

ABSTRACT The use of products that promote reduction of nitrogen (N) losses from the urea fertilizer can contribute to increasing its use efficiency in forage grasses. This study aimed to evaluate the effects of N sources and doses on the growth of Urochloa ruziziensis. The experiment was carried out in the growing season of 2007/2008 in Santo Antônio de Goiás-GO, in a Brazilian Oxisol. A completely randomized block was used, with four replicates in a factorial scheme, corresponding to two N sources (conventional urea and urea with urease inhibitor) and five N doses (0, 50, 100, 200 and 300 kg ha-1), divided into equal applications in five periods (Nov 14 to Dec 13, Dec 14 to Jan 12, Jan 13 to Feb 11 - rainy season, Mar 24 to Apr 22 and Jul 10 to Aug 08 - dry season). The effects of the treatments were evaluated for: shoot dry matter, tiller density, total N content in the leaves and relative chlorophyll content. N fertilizer sources did not affect the evaluated variables; however, N fertilization allowed linear increases in all variables with higher values during the rainy period. The relative chlorophyll content in U. ruziziensis had positive correlation with its dry matter productivity.

John Stewart Turner

1999 ◽  
Vol 47 (4) ◽  
pp. iii
Author(s):  
Kingsley S. Rowan ◽  
David H. Ashton
Keyword(s):  
Chlorophyll Content ◽  
Dry Matter ◽  
Vapor Pressure Deficit ◽  
Acacia Saligna ◽  
Wood Production ◽  
Carbon Isotope Ratios ◽  
Drought Conditions ◽  
Use Efficiency ◽  
Demand Control ◽  
Air Vapor Pressure Deficit

Acacia saligna (Labill.) H.Wendl, a potential crop for forage and wood production, is considered highly drought-resistant. The aim of this study was to characterise some of the physiological traits contributing to drought resistance in A. saligna. Two experiments were conducted: (i) 4-year-old A. saligna were grown in the field under dryland and irrigated treatments and (ii) 6-month-old A. saligna were grown in pots and irrigated to replenish 100% of the transpiration demand (control), or 75% 50% or 25% of the control. Soil-water deficits in the field elicited an increase in osmotic potential in phyllodes. Stomatal conductance was negatively correlated with air vapor pressure deficit under drought conditions in both experiments, whereas under irrigation in the field it was correlated with solar radiation. In the field, dry matter (DM) production under irrigation was only 14% greater (not significant) than under dryland. In the pot experiment, DM production was significantly reduced, and water use efficiency (WUE) and chlorophyll content increased with reduced availability of water. The greater WUE induced by drought could have resulted from stomatal regulation and increased chlorophyll content. Carbon isotope ratios were correlated with the WUE, and may be utilised for selection to further improve the WUE of A. saligna under drought conditions.

Nitrogen use efficiency of different slurry management in the pre-alpine grassland region – a 15N tracing experiment

2020 ◽  
Author(s):  
Marcus Zistl-Schlingmann ◽  
Steve Kwatcho-Kengdo ◽  
Mirella Schreiber ◽  
Bernd Berauer ◽  
Anke Jentsch ◽  
...  
Keyword(s):  
Climate Change ◽  
Soil Nitrogen ◽  
Nitrogen Use Efficiency ◽  
Cattle Slurry ◽  
N Losses ◽  
Nitrogen Use ◽  
Total N ◽  
Plant Nitrogen ◽  
Plant Soil ◽  
Use Efficiency

<p>Grasslands of the alpine and pre-alpine region do not only sustain economic soil functions such as fodder production for local dairy and cattle farming but also important ecological soil functions such as water and nutrient retention, erosion and flood protection and habitat provision for extraordinarily high plant and animal biodiversity. The current management in the more intensively used grasslands in this region is based on fertilization with liquid cattle slurry, which is assumed to be prone to high N leaching and gaseous N emissions with their undesired consequences for soil, air and water quality.</p><p>In order to assess the nitrogen use efficiency and trade-offs such as greenhouse gas emissions and nitrate leaching of liquid slurry surface application under the auspices of climate change, we set up a <sup>15</sup>N cattle slurry labeling experiment, combined with a space for time climate change experiment using plant-soil mesocosms and lysimeters. The <sup>15</sup>N signal was traced in the plant-soil-microbe system for an entire year to assess productivity, plant nitrogen use efficiency, soil nitrogen retention and nitrogen losses. We found surprisingly low plant nitrogen use efficiency (recovery of less than ¼ of the applied <sup>15</sup>N in harvested plant biomass), soil N retention (ca ¼ <sup>15</sup>N recovery) and high environmental N losses (ca ½ of the <sup>15</sup>N tracer remained unrecovered). The estimates of N losses based on unrecovered <sup>15</sup>N were in good agreement with independent measurements of gaseous and hydrological N losses. Due to very high productivity and associated N exports with grass harvests, total N exports exceeded total N inputs. Such soil nitrogen mining was especially pronounced in the climate change treatments and was supported by increased soil nitrogen mineralization.</p><p>We also tested alternative slurry management (slurry injection into the soil, slurry acidification) that is supposed to increase nitrogen use efficiency. Slurry acidification but not slurry injection slightly increased plant nitrogen use efficiency and reduced nitrogen losses, however could overall not prevent significant soil nitrogen mining.</p><p>Consequently, both surface application and the more modern techniques of liquid cattle slurry fertilization showed low nitrogen use efficiency and promoted soil nitrogen mining. This is asking for a re-consideration of traditional fertilization regimes based on solid manure mixed with straw, a management that over historical timescales likely contributed to the build up of the large nitrogen stocks in pre-alpine grassland soils.</p>

scholarly journals Temporal and Organ-specific Responses in NUE Traits to N Fertilization, Fungicide Intensity and Early Sowing in Winter Wheat Cultivars

Agronomy ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 313 ◽  
Author(s):  
Lukas Prey ◽  
Moritz Germer ◽  
Urs Schmidhalter
Keyword(s):  
Winter Wheat ◽  
Harvest Index ◽  
N Uptake ◽  
N Fertilization ◽  
N Use Efficiency ◽  
Control Treatment ◽  
Total N ◽  
Organ Specific ◽  
Use Efficiency ◽  
N Use

Fungicide intensity and sowing time influence the N use efficiency (NUE) of winter wheat but the underlying mechanisms, interactions of plant traits, and the temporal effects are not sufficiently understood. Therefore, organ-specific responses in NUE traits to fungicide intensity and earlier sowing were compared at two nitrogen (N) levels for six winter wheat cultivars in 2017. Plants were sampled at anthesis and at maturity and separated into chaff, grain, culms, and three leaf layers to assess their temporal contribution to aboveground dry matter (DM) and N uptake (Nup). Compared to the control treatment, across cultivars, the treatment without fungicide mostly exerted stronger and inverse effects than early sowing, on grain yield (GY, −12% without fungicide, +8% n.s. for early sowing), grain Nup (GNup, −9% n.s., +5% n.s.) as well as on grain N concentration (+4%, −2% n.s.). Grain yield in the treatment without fungicide was associated with similar total DM, as observed in the control treatment but with lower values in harvest index, thousand kernel weight, N use efficiency for GY (NUE) and N utilization efficiency. Lower GNup was associated with similar vegetative N uptake but lower values in N translocation efficiency and N harvest index. In contrast, early sowing tended to increase total DM at anthesis and maturity as well as post-anthesis assimilation, at similar harvest index and increased the number of grains per spike and total N use efficiency. Total N uptake increased after the winter season but was similar at anthesis. Although the relative N response in many traits was lower without fungicide, few fungicide x interactions were significant, and the sowing date did not interact either with N fertilization for any of the N and DM traits. The results demonstrate the positive effects of fungicides and earlier sowing on various traits related to yield formation and the efficient use of nitrogen and are discussed based on various concepts.

scholarly journals Nitrogen in Water-Portugal and Denmark: Two Contrasting Realities

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1114 ◽  
Author(s):  
Soraia Cruz ◽  
Cláudia M.d.S. Cordovil ◽  
Renata Pinto ◽  
António G. Brito ◽  
Maria R. Cameira ◽  
...  
Keyword(s):  
Water Quality ◽  
Surface Waters ◽  
Mineral Fertilizer ◽  
N Losses ◽  
Total N ◽  
Policy Responses ◽  
Mainland Portugal ◽  
Water Quality Status ◽  
Use Efficiency ◽  
The Impact

Agricultural activities are responsible for most of the nitrogen (N) inputs that degrade water quality. To elucidate the drivers leading to N pressures on water, we examined the resulting state of surface waters in terms of N concentrations, the impact of this on water quality status and policy responses to these constraints across different climatic and management conditions. Portugal and Denmark were chosen as contrasting case studies for the Driver-Pressure-State-Impact-Response (DPSIR) analysis. Our results showed reductions of 39% and 25% in the use of mineral fertilizer in Portugal and Denmark, respectively, between 2000 and 2010. The N surplus in Portugal varied between 15 and 30 kg N ha−1 between 1995 and 2015. In Denmark, in 2015, this amount was 70 kg N ha−1, representing a 53% decrease from the 1990 value. The average amount of total N discharged to surface waters was 7 kg ha−1 for mainland Portugal in 2015 and 14.6 kg ha−1 for Denmark in 2014. These reductions in the N surplus were attributed to historical policies aimed at N pressure abatement. In Denmark, N losses are expected to decline further through the continuation or improvement of existing national action plans. In Portugal, they are expected to decline further due to the expansion of Nitrate Vulnerable Zones and the introduction of targeted policies aimed at improving N use efficiency and reducing losses to water.

scholarly journals Nutritional status and fruit production of Carica papaya as a function of coated and conventional urea

2016 ◽  
Vol 20 (4) ◽  
pp. 322-328 ◽  
Author(s):  
Gabriel B. da Silva Júnior ◽  
Eduardo M. dos Santos ◽  
Roberto L. Silva ◽  
Ítalo H. L. Cavalcante
Keyword(s):  
Fruit Production ◽  
N Fertilization ◽  
Soil Mineral ◽  
Experimental Conditions ◽  
N Losses ◽  
Mineral N ◽  
N Sources ◽  
N Release ◽  
Coated Urea ◽  
Polymer Coated Urea

ABSTRACT As a strategy to minimize N losses in the soil, mineral N sources, such as polymer-coated urea, have been studied as possibility to increase the synchronization of N release by the fertilizer and its absorption by plants. Thus, this study aimed to evaluate the contents of macronutrients and the production of Formosa papaya as a function of sources and doses of N fertilizer applied as top-dressing in the region of Bom Jesus-PI, Brazil. The treatments were arranged in a 2 x 4 factorial scheme corresponding to N sources (coated urea and conventional urea) and N doses (350, 440, 530 and 620 g plant-1 of N), with four replicates and four plants per plot. The contents of macronutrients in the leaf dry matter and fruit production were evaluated. The sources and doses of top-dressing N fertilization incremented the leaf contents of macronutrients and the production of Formosa papaya hybrid Caliman 01. Under the experimental conditions and based on the macronutrient contents considered as adequate for crop nutrition, associated with maximum fruit production (8.08 kg plant-1), the supply of 525 g of N plant-1 is recommended in the form of coated urea.

The course of fertilizer nitrogen uptake by rainfed sugarcane in Mauritius

1994 ◽  
Vol 122 (3) ◽  
pp. 385-391 ◽  
Author(s):  
K. F. Ng Kee Kwong ◽  
J. Deville
Keyword(s):  
Dry Matter ◽  
N Uptake ◽  
N Recovery ◽  
Dry Matter Accumulation ◽  
Fertilizer N ◽  
N Losses ◽  
Total N ◽  
Fertilizer N Recovery ◽  
The Difference ◽  
Fertilizer N Uptake

SUMMARYThe patterns of N uptake and dry matter synthesis by sugarcane (Saccharum hybrid spp.) were studied at four locations in Mauritius with 15N–labelled ammonium sulphate (100 kg N/ha) applied either in a single dressing in September or in two split applications in September and the following February. More than 80% of the total N recovered at harvest (100–120 kgN/ha) was absorbed by the sugarcane during an active uptake period from October to January. Split application prolonged this active N uptake until April only and had no effect on dry matter accumulation. While total Nabsorbed by above-ground sugarcane showed no decline over time, 10–20 kg N/ha of the 15N–labelled N was lost from the green tops even when the N was applied on two occasions. The fertilizer N losses from above-ground sugarcane were, however, not evident when fertilizer N recovery with time was studied by the difference method. In view of the observed losses of fertilizer N from the aerial parts of sugarcane, measurement of fertilizer N recovery at harvest by the N isotope dilution technique underestimates fertilizer N uptake by sugarcane and attributes too large a fraction of N loss to denitrification/volatilization of NH3.

Rate and timing of nitrogen fertilization of Russet Burbank potato: Nitrogen use efficiency

2004 ◽  
Vol 84 (3) ◽  
pp. 845-854 ◽  
Author(s):  
B. J. Zebarth ◽  
Y. Leclerc ◽  
G. Moreau
Keyword(s):  
Dry Matter ◽  
N Fertilization ◽  
N Use Efficiency ◽  
Fertilizer N ◽  
Inorganic N ◽  
N Accumulation ◽  
N Supply ◽  
Soil Inorganic N ◽  
Use Efficiency ◽  
N Use

This study evaluated rate and timing of N fertilization effects on the N use efficiency characteristics of rain-fed Russet Burbank potato. Trials conducted in 1999–2001 included different rates of fertili zer N (0–160 kg N ha-1 in 1999 and 0–200 kg N ha-1 in 2000 and 2001) applied either at planting according to normal grower practice, or at hilling, the latest time that granular fertilizer can practically be applied. Whole-plant dry matter and N accumulation were determined at topkill. Soil inorganic N content was measured to 30-cm depth at planting and at tuber harvest. Soil N supply (plant N accumulation plus soil inorganic N content at harvest with no fertilizer N applied) varied from 77 to 146 kg N ha-1 depending on the year. Crop N supply (soil N supply plus fertilizer N applied) was a better predictor of plant N accumulation than fertilizer N rate, and was used to remove the confounding effect of variation in soil N supply when making among-year comparisons for N use efficiency characteristics. Nitrogen uptake efficiency (NUpE; plant N accumulation/crop N supply) decreased with increasing rates of N applied at hilling N rate in 1999, which was a dry year, but was not influenced by at-hilling N rate in 2000 and 2001, or by at-planting N rate in any year. Nitrogen use efficiency (NUE; dry matter accumulation/crop N supply) and N utilization efficiency (NUtE; dry matter accumulation/plant N accumulation) decreased curvilinearly with increasing crop N supply in each year. Similar relationships between NUE and crop N supply, and between NUtE and plant N accumulation, among the 3 yr of the study suggest that these relationships are largely independent of seasonal climatic variation, and are primarily genetically controlled. Timing of N fertilization had no effect on any N use efficiency parameter, with the exception of reduced NUpE associated with split N application in 1999. This suggests that under rain-fed potato production in Atlantic Canada, timing of N fertilization has no significant effect on N use efficiency of Russet Burbank potato in years of adequate soil moisture, but NUpE may be decreased by split application of N in dry years. Key words: Solanum tuberosum, soil inorganic N, apparent fertilizer N recovery

scholarly journals Glutacetine® Biostimulant Applied on Wheat under Contrasting Field Conditions Improves Grain Number Leading to Better Yield, Upgrades N-Related Traits and Changes Grain Ionome

Plants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 456
Author(s):  
Victor Maignan ◽  
Patrick Géliot ◽  
Jean-Christophe Avice
Keyword(s):  
Grain Yield ◽  
Temperate Climate ◽  
Grain Number ◽  
N Losses ◽  
Total N ◽  
P Content ◽  
Grain Number Per Spike ◽  
Grain Yield Components ◽  
Use Efficiency ◽  
Mn Content

Wheat is one of the most important cereals for human nutrition, but nitrogen (N) losses during its cultivation cause economic problems and environmental risks. In order to improve N use efficiency (NUE), biostimulants are increasingly used. The present study aimed to evaluate the effects of Glutacetine®, a biostimulant sprayed at 5 L ha−1 in combination with fertilizers (urea or urea ammonium nitrate (UAN)), on N-related traits, grain yield components, and the grain quality of winter bread wheat grown at three field sites in Normandy (France). Glutacetine® improved grain yield via a significant increase in the grain number per spike and per m2, which also enhanced the thousand grain weight, especially with urea. The total N in grains and the NUE tended to increase in response to Glutacetine®, irrespective of the site or the form of N fertilizer. Depending on the site, spraying Glutacetine® can also induce changes in the grain ionome (analyzed by X-ray fluorescence), with a reduction in P content observed (site 2 under urea nutrition) or an increase in Mn content (site 3 under UAN nutrition). These results provide a roadmap for utilizing Glutacetine® biostimulant to enhance wheat production and flour quality in a temperate climate.

scholarly journals Nitrate Uptake and Nitrogen Use Efficiency of Two Sweetpotato Genotypes during Early Stages of Storage Root Formation

1998 ◽  
Vol 123 (5) ◽  
pp. 814-820 ◽  
Author(s):  
Margarita R. Villagarcia ◽  
Wanda W. Collins ◽  
C. David Raper
Keyword(s):  
Nutrient Solution ◽  
Dry Matter ◽  
N Availability ◽  
Dry Matter Accumulation ◽  
Storage Root ◽  
Storage Roots ◽  
Total N ◽  
Use Efficiency ◽  
Complete Nutrient Solution ◽  
N Use

Soil N availability is an important component in storage root production of sweetpotato [Ipomoea batata (L.) Lam.]. A controlled-environment experiment was conducted to characterize effects of N availability on patterns of dry matter, nonstructural carbohydrates, and N accumulation, and to determine possible components of N use efficiency that vary between two genotypes of sweetpotato. Rooted cuttings of `Jewel' and MD810 were transplanted into pots filled with sand and kept in a growth chamber for 72 days. Plants were watered during the first 30 days with a complete nutrient solution that contained 14 mm NO3- and then for the next 42 days with one of three complete nutrient solution that contained either 2, 8, or 14 mm NO3-. At 30, 44, 58, and 72 days after transplanting, three plants from each cultivar and treatment combination were sampled and separated into leaves, stems plus petioles, fibrous roots, and storage roots. Each plant fraction was freeze-dried, weighed, ground, and analyzed for total N, soluble sugars, and starch. Availability of N in the substrate, which limited dry matter accumulation at 2 mm NO3-, was nonlimiting at 8 and 14 mm NO3-. In both genotypes, net assimilation rate, efficiency of N use (i.e., increments of dry matter accumulated per increment of N taken up), and proportion of dry matter allocated to storage roots were greater for N-stressed (2 mm NO3-) than N-replete (8 and 14 mm NO3-) plants. For the N-stressed plants, however, efficiency of N use was greater in MD810 than in `Jewel'. Although rate of NO3- uptake per unit fibrous root mass was similar in the two genotypes under the N stress treatment, MD810 had greater uptake rate than `Jewel' under nonlimiting availability of NO3- in the substrate. The increased rate of uptake under nonlimiting NO3- supplies apparently was related to enhanced rates of carbohydrate transport from shoots to roots. As tissue concentration of N declined in response to the lowest application of NO3-, shoot growth was limited prior to, and to a greater extent than, the photosynthetic rate. The resulting relative decline in sink activity of shoots thus presumably increased the availability of carbohydrates for transport to roots.

scholarly journals Dry matter and nitrogen accumulation and use in spring barley

2011 ◽  
Vol 49 (No. 1) ◽  
pp. 36-47 ◽  
Author(s):  
N. Przulj ◽  
V. Momčilović
Keyword(s):  
Dry Matter ◽  
Spring Barley ◽  
Grain Filling ◽  
Nitrogen Accumulation ◽  
Dry Matter Accumulation ◽  
Hordeum Vulgare L ◽  
N Losses ◽  
N Accumulation ◽  
Total N ◽  
Growing Conditions

During growth, kernel of cereals can be provided with carbohydrate and nitrogen (N) from the translocation of pre-anthesis accumulated reserves stored either in the vegetative plant parts or from current assimilation during kernel development. This study was conducted to assess the effects of nitrogen level and cultivars on dry matter and N accumulation and mobilization during pre-anthesis and post-anthesis. Twenty two-rowed spring barley (Hordeum vulgare L.) cultivars were grown on a non-calcareous chernozem soil in four growing seasons (1995–1998) atNovi Sad (45°20'N, 15°51'E,86 m a.s.l.) at two nitrogen levels. Dry matter accumulation before anthesis ranged from less than 50% in unfavorable to 90% in favorable growing conditions. Dry matter translocation occurred in favorable growing conditions only. Pre-anthesis accumulated N represented 57–92% and 54–129% of total N at maturity at the low and high N levels, respectively. Translocated N represented 41–85% and 37–153% of grain N at the low and high N level, respectively. N losses occurred in favorable growing conditions when anthesis N exceeded 150 kg/ha. N accumulation during grain filling was in negative correlation with dry matter and N accumulation before anthesis. The N harvest index was 0.57–0.63 and 0.71–0.74 in unfavorable and favorable growing conditions, respectively. Selection of genotypes with a higher ability of pre-anthesis reserve utilization or genotypes with longer leaf area duration after anthesis may be two possible solutions in spring barley breeding for Mediterranean growing conditions.

Sign in / Sign up

Export Citation Format

Share Document