Effects of placement of urea with a urease inhibitor on seedling emergence, N uptake and dry matter yield of wheat

Growth chamber studies were conducted to determine the effect of seed-placed and surface dribble-banded urea fertilizer, with and without the addition of two levels of the urease inhibitor N-(n-butyl) thiophosphoric triamide (nBTPT) on seedling emergence, vegetative yield and nitrogen accumulation of hard red spring wheat. Seedling emergence was reduced with increasing applications of seed-placed urea, but nBTPT reduced the damage from seed-placed urea. The 0.15% inhibitor level was as effective as the 0.25% level in reducing seedling damage. Vegetative yield increased with application of urea fertilizer but no difference in vegetative yield resulted from varying fertilizer placement or additions of nBTPT. Nitrogen accumulation increased with increasing N application and with the use of the urease inhibitor, indicating an increase in N availability due to slowing of urea hydrolysis. Use of the urease inhibitor nBTPT shows promise in reducing seedling damage from seed-placed urea fertilizer and increasing the utilization of seed-placed and surface-applied urea fertilizer on a black Chernozemic soil. Further studies are in progress to assess the performance of nBTPT under field conditions. Key words: N-(n-butyl) thiophosphoric triamide

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Stimulation of Common Cocklebur (Xanthium pensylvanicum) and Redroot Pigweed (Amaranthus retroflexus) Seed Germination by Injections of Ethylene into Soil

Weed Science ◽

10.1017/s0043174500061129 ◽

1980 ◽

Vol 28 (5) ◽

pp. 510-514 ◽

Cited By ~ 18

Author(s):

G. H. Egley

Keyword(s):

Seed Germination ◽

Laboratory Tests ◽

Seedling Emergence ◽

Amaranthus Retroflexus ◽

Redroot Pigweed ◽

Plastic Bags ◽

Viable Seeds ◽

Chamber Studies ◽

Growth Chamber Studies ◽

Stimulation Of

The effects of ethylene upon germination of common cocklebur (Xanthium pensylvanicumWallr.) and redroot pigweed (Amaranthus retroflexusL.) seeds were studied. In laboratory tests with seeds in sealed flasks in the dark, 10 μl/L ethylene increased germination of redroot pigweed seeds from 7% to 52% at 30 C, and increased germination of large and small common cocklebur seeds from 30% and 0% to 100% and 90% respectively, at 25 C. At least 12 h of exposure to ethylene was necessary for appreciable stimulation of germination. In growth chamber studies with known numbers of seeds in pots of soil, ethylene at 11 kg/ha was injected into the soil, and the pots were enclosed in plastic bags for 24 h. One such injection at 2 weeks after planting, and successive injections at 2, 3, and 4 weeks, significantly increased redroot pigweed seedling emergence, and significantly decreased the numbers of dormant, viable seeds remaining in the soil. When pots were not enclosed, injections did not significantly effect redroot pigweed seeds, but significantly increased common cocklebur seedling emergence and decreased the number of viable common cocklebur seeds remaining in the soil.

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Modeling weed emergence as influenced by burial depth using the Fermi-Dirac distribution function

Weed Science ◽

10.1017/s004317450009278x ◽

1997 ◽

Vol 45 (2) ◽

pp. 242-248 ◽

Cited By ~ 10

Author(s):

Eric P. Prostko ◽

Hsin-I Wu ◽

James M. Chandler ◽

Scott A. Senseman

Keyword(s):

Distribution Function ◽

Abiotic Factors ◽

Seedling Emergence ◽

Model Parameters ◽

Burial Depth ◽

Data Sets ◽

Downy Brome ◽

Dirac Distribution ◽

Chamber Studies ◽

Growth Chamber Studies

Research was conducted to determine the suitability of the Fermi-Dirac distribution function for modeling the seedling emergence of downy brome, johnsongrass, and round-leaved mallow, as influenced by burial depth. Six sets of previously published emergence data were used to formulate the model and test its adequacy. Two independent johnsongrass emergence data sets were used to validate the model. Constant temperature growth chamber studies were conducted to evaluate the effects of temperature and moisture on the model parameters. The Fermi-Dirac distribution function was found to adequately describe the seedling emergence of downy brome, johnsongrass, and round-leaved mallow as indicated by a good visual data fit, narrow confidence intervals for the model parameters, and regression analysis of observed vs. modeled data. Although this function is a model used in physical science, its parameters can be related to abiotic factors such as soil texture, temperature, and moisture.

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Seed Germination and Seedling Emergence of Scotch Broom (Cytisus scoparius)

Weed Science ◽

10.1614/ws-09-078.1 ◽

2009 ◽

Vol 57 (6) ◽

pp. 620-626 ◽

Cited By ~ 7

Author(s):

Timothy B. Harrington

Keyword(s):

Seed Germination ◽

Temperature Regime ◽

Root Biomass ◽

Seedling Emergence ◽

Soil Drought ◽

Dark Light ◽

Scotch Broom ◽

Effects Of Temperature ◽

Chamber Studies ◽

Growth Chamber Studies

Scotch broom is a large, leguminous shrub that has invaded 27 U.S. states. The species produces seeds with a hard coat that remain viable in the soil for years. Growth-chamber studies were conducted to determine effects of temperature regime and cold-stratification period on seed germination. Seedling emergence, mortality, and biomass also were studied in response to sulfometuron and metsulfuron herbicides and variation in soil texture and watering regime. Germination was greatest for a dark/light temperature regime of 15/20 C. Initial rates of germination increased as stratification period was varied from 0 to 60 d, but final germination after 90 d did not differ significantly among periods. Applied alone or in combination, sulfometuron and metsulfuron decreased biomass and increased mortality of seedlings. Mortality from simulated soil drought was greater in the presence versus absence of sulfometuron (20 and 6% mortality, respectively) probably because the herbicide reduced root biomass by 58 to 95%. Invasiveness of Scotch broom is facilitated by a prolonged period of germination across a broad temperature range. Increased control of Scotch broom seedlings with sulfometuron is likely if application is timed to expose recently emerged seedlings to developing conditions of soil drought.

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Biochar and urease inhibitor mitigate NH3 and N2O emissions and improve wheat yield in a urea fertilized alkaline soil

Scientific Reports ◽

10.1038/s41598-021-96771-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Khadim Dawar ◽

Shah Fahad ◽

M. M. R. Jahangir ◽

Iqbal Munir ◽

Syed Sartaj Alam ◽

...

Keyword(s):

Nitrous Oxide ◽

Grain Yield ◽

Block Design ◽

N Uptake ◽

Nitrous Oxide Emissions ◽

N2o Emissions ◽

Urease Inhibitor ◽

Alkaline Soil ◽

Total N ◽

N Assimilation

AbstractIn this study, we explored the role of biochar (BC) and/or urease inhibitor (UI) in mitigating ammonia (NH3) and nitrous oxide (N2O) discharge from urea fertilized wheat cultivated fields in Pakistan (34.01°N, 71.71°E). The experiment included five treatments [control, urea (150 kg N ha−1), BC (10 Mg ha−1), urea + BC and urea + BC + UI (1 L ton−1)], which were all repeated four times and were carried out in a randomized complete block design. Urea supplementation along with BC and BC + UI reduced soil NH3 emissions by 27% and 69%, respectively, compared to sole urea application. Nitrous oxide emissions from urea fertilized plots were also reduced by 24% and 53% applying BC and BC + UI, respectively, compared to urea alone. Application of BC with urea improved the grain yield, shoot biomass, and total N uptake of wheat by 13%, 24%, and 12%, respectively, compared to urea alone. Moreover, UI further promoted biomass and grain yield, and N assimilation in wheat by 38%, 22% and 27%, respectively, over sole urea application. In conclusion, application of BC and/or UI can mitigate NH3 and N2O emissions from urea fertilized soil, improve N use efficiency (NUE) and overall crop productivity.

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Development of an Online Tool for Tracking Soil Nitrogen to Improve the Environmental Performance of Maize Production

Sustainability ◽

10.3390/su13105649 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5649

Author(s):

Giovani Preza-Fontes ◽

Junming Wang ◽

Muhammad Umar ◽

Meilan Qi ◽

Kamaljit Banger ◽

...

Keyword(s):

Real Time ◽

N Uptake ◽

Growing Season ◽

Weather Data ◽

N Availability ◽

Soil N ◽

N Losses ◽

Online Tool ◽

Support Tool ◽

Soil N Availability

Freshwater nitrogen (N) pollution is a significant sustainability concern in agriculture. In the U.S. Midwest, large precipitation events during winter and spring are a major driver of N losses. Uncertainty about the fate of applied N early in the growing season can prompt farmers to make additional N applications, increasing the risk of environmental N losses. New tools are needed to provide real-time estimates of soil inorganic N status for corn (Zea mays L.) production, especially considering projected increases in precipitation and N losses due to climate change. In this study, we describe the initial stages of developing an online tool for tracking soil N, which included, (i) implementing a network of field trials to monitor changes in soil N concentration during the winter and early growing season, (ii) calibrating and validating a process-based model for soil and crop N cycling, and (iii) developing a user-friendly and publicly available online decision support tool that could potentially assist N fertilizer management. The online tool can estimate real-time soil N availability by simulating corn growth, crop N uptake, soil organic matter mineralization, and N losses from assimilated soil data (from USDA gSSURGO soil database), hourly weather data (from National Weather Service Real-Time Mesoscale Analysis), and user-entered crop management information that is readily available for farmers. The assimilated data have a resolution of 2.5 km. Given limitations in prediction accuracy, however, we acknowledge that further work is needed to improve model performance, which is also critical for enabling adoption by potential users, such as agricultural producers, fertilizer industry, and researchers. We discuss the strengths and limitations of attempting to provide rapid and cost-effective estimates of soil N availability to support in-season N management decisions, specifically related to the need for supplemental N application. If barriers to adoption are overcome to facilitate broader use by farmers, such tools could balance the need for ensuring sufficient soil N supply while decreasing the risk of N losses, and helping increase N use efficiency, reduce pollution, and increase profits.

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Morphological and Physiological Root Traits and Their Relationship with Nitrogen Uptake in Wheat Varieties Released from 1915 to 2013

Agronomy ◽

10.3390/agronomy11061149 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1149

Author(s):

Guglielmo Puccio ◽

Rosolino Ingraffia ◽

Dario Giambalvo ◽

Gaetano Amato ◽

Alfonso S. Frenda

Keyword(s):

Durum Wheat ◽

Root System ◽

N Uptake ◽

Specific Root Length ◽

Root Traits ◽

Wheat Breeding ◽

N Availability ◽

Wheat Varieties ◽

Uptake Efficiency ◽

Positive Effects

Identifying genotypes with a greater ability to absorb nitrogen (N) may be important to reducing N loss in the environment and improving the sustainability of agricultural systems. This study extends the knowledge of variability among wheat genotypes in terms of morphological or physiological root traits, N uptake under conditions of low soil N availability, and in the amount and rapidity of the use of N supplied with fertilizer. Nine genotypes of durum wheat were chosen for their different morpho-phenological characteristics and year of their release. The isotopic tracer 15N was used to measure the fertilizer N uptake efficiency. The results show that durum wheat breeding did not have univocal effects on the characteristics of the root system (weight, length, specific root length, etc.) or N uptake capacity. The differences in N uptake among the studied genotypes when grown in conditions of low N availability appear to be related more to differences in uptake efficiency per unit of weight and length of the root system than to differences in the morphological root traits. The differences among the genotypes in the speed and the ability to take advantage of the greater N availability, determined by N fertilization, appear to a certain extent to be related to the development of the root system and the photosynthesizing area. This study highlights some variability within the species in terms of the development, distribution, and efficiency of the root system, which suggests that there may be sufficient grounds for improving these traits with positive effects in terms of adaptability to difficult environments and resilience to climate change.

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Genotypic Difference in the Responses to Nitrogen Fertilizer Form in Tibetan Wild and Cultivated Barley

Plants ◽

10.3390/plants10030595 ◽

2021 ◽

Vol 10 (3) ◽

pp. 595

Author(s):

Shama Naz ◽

Qiufang Shen ◽

Jonas Lwalaba Wa Lwalaba ◽

Guoping Zhang

Keyword(s):

Wild Barley ◽

Growth Parameters ◽

Inorganic Nitrogen ◽

N Uptake ◽

Total Soluble Protein ◽

Organic N ◽

Genotypic Difference ◽

N Availability ◽

Tibetan Wild Barley ◽

Cultivated Barley

Nitrogen (N) availability and form have a dramatic effect on N uptake and assimilation in plants, affecting growth and development. In the previous studies, we found great differences in low-N tolerance between Tibetan wild barley accessions and cultivated barley varieties. We hypothesized that there are different responses to N forms between the two kinds of barleys. Accordingly, this study was carried out to determine the response of four barley genotypes (two wild, XZ16 and XZ179; and two cultivated, ZD9 andHua30) under 4Nforms (NO3−, NH4+, urea and glycine). The results showed significant reduction in growth parameters such as root/shoot length and biomass, as well as photosynthesis parameters and total soluble protein content under glycine treatment relative to other N treatments, for both wild and cultivated barley, however, XZ179 was least affected. Similarly, ammonium adversely affected growth parameters in both wild and cultivated barleys, with XZ179 being severely affected. On the other hand, both wild and cultivated genotypes showed higher biomass, net photosynthetic rate, chlorophyll and protein in NO3− treatment relative to other three N treatments. It may be concluded that barley undisputedly grows well under inorganic nitrogen (NO3−), however in response to the organic N wild barley prefer glycine more than cultivated barely.

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Effect of different levels of humic acids on the nutrient content, plant growth, and soil properties under conditions of salinity

Soil and Water Research ◽

10.17221/4/2010-swr ◽

2011 ◽

Vol 6 (No. 1) ◽

pp. 21-29 ◽

Cited By ~ 65

Author(s):

H. Khaled ◽

H.A. Fawy

Keyword(s):

Plant Growth ◽

Humic Substances ◽

Humic Acids ◽

Foliar Application ◽

N Uptake ◽

Seedling Emergence ◽

Dry Weight ◽

Nutrient Content ◽

Nutrient Elements ◽

A Minor

In this study, the effects were investigated of salinity, foliar and soil applications of humic substances on the growth and mineral nutrients uptake of Corn (Hagein, Fardy10), and the comparison was carried out of the soil and foliar applications of humic acid treatments at different NaCl levels. Soil organic contents are one of the most important parts that they directly affect the soil fertility and textures with their complex and heterogenous structures although they occupy a minor percentage of the soil weight. Humic acids are an important soil component that can improve nutrient availability and impact on other important chemical, biological, and physical properties of soils. The effects of foliar and soil applications of humic substances on the plant growth and some nutrient elements uptake of Corn (Hagein, Fardy10) grown at various salt concentrations were examined. Sodium chloride was added to the soil to obtain 20 and 60mM saline conditions. Solid humus was applied to the soil one month before planting and liquid humic acids were sprayed on the leaves twice on 20<sup>th</sup> and 40<sup>th</sup> day after seedling emergence. The application doses of solid humus were 0, 2 and 4 g/kg and those of liquid humic acids were 0, 0.1 and 0.2%. Salinity negatively affected the growth of corn; it also decreased the dry weight and the uptake of nutrient elements except for Na and Mn. Soil application of humus increased the N uptake of corn while foliar application of humic acids increased the uptake of P, K, Mg,Na,Cu and Zn. Although the effect of interaction between salt and soil humus application was found statistically significant, the interaction effect between salt and foliar humic acids treatment was not found significant. Under salt stress, the first doses of both soil and foliar application of humic substances increased the uptake of nutrients.

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Response of Rice Nitrogen Physiology to High Nighttime Temperature during Vegetative Stage

The Scientific World JOURNAL ◽

10.1155/2013/649326 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Song Chen ◽

Xiaoguo Zhang ◽

Xia Zhao ◽

Danying Wang ◽

Chunmei Xu ◽

...

Keyword(s):

N Uptake ◽

Plant Morphology ◽

Carbohydrate Content ◽

Shoot Biomass ◽

Nitrogen Accumulation ◽

Root Volume ◽

Nitrogen Levels ◽

Soluble Leaf Protein ◽

Nitrogen Concentrations ◽

Positive Effect

The effects of night temperature on plant morphology and nitrogen accumulation were examined in rice (Oryza sativaL.) during vegetative growth. The results showed that the shoot biomass of the plants was greater at 27°C (high nighttime temperature, HNT) than at 22°C (CK). However, the increase in both shoot and root biomasses was not significant under 10 mg N/L. The shoot nitrogen concentrations were 16.1% and 16.7% higher in HNT than in CK under 160 and 40 mg N/L. These results suggest that plant N uptake was enhanced under HNT; however, the positive effect might be limited by the N status of the plants. In addition, leaf area, plant height, root maximum length, root and shoot nitrogen concentrations, soluble leaf protein content, and soluble leaf carbohydrate content were greater in HNT than in CK under 40 and 160 mg N/L, while fresh root volume, root number, and the content of free amino acid in leaf were not significantly different between HNT and CK regardless of nitrogen levels. Moreover, leaf GS activity under HNT was increased at 160 mg N/L compared with that under CK, which might partly explain the positive effect of HNT on soluble protein and carbohydrate content.

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