Effect of field peas and wheat on the yield and protein content of subsequent wheat crops grown at several rates of applied nitrogen

1994 ◽  
Vol 34 (5) ◽  
pp. 641 ◽  
Author(s):  
IC Rowland ◽  
MG Mason ◽  
IA Pritchard ◽  
RJ French
Keyword(s):  
N Availability ◽  
Average Increase ◽  
Average Yield ◽  
Response Curves ◽  
Yield Data ◽  
Yield Increase ◽  
Field Peas ◽  
Quadratic Response ◽  
The Difference ◽  
Rate Interaction

The responses of wheat to various rates of N fertiliser were compared following field peas (PW) or wheat (WW) in the previous year. Seventeen trials were carried out at 5 sites between 1986 and 1991. The trials were on medium- and fine-textured soils (clay loams or shallow duplex soils). The overall grain yield of PW appeared greater than WW in 11 trials [was significantly greater in 9 (P<0.05)], and did not appear different in 6 trials. When no N was applied the yield advantage of PW was 41% (PW 1.91 t/ha cf. WW 1.37 t/ha). Quadratic response curves were fitted to all yield data. Rotation x N rate interaction was significant (P<0.05) in 10 comparisons. In 5 trials, while there was a yield increase to N fertiliser with WW, the yields decreased with PW. In 3 trials while there was an increase with WW there was no response with PW or a reduction at higher rates of N. In the remaining 2 trials there were responses with both PW and WW, but this was greater for WW. The response curves in these 10 trials either converged and met, indicating that the difference between rotations was due to N availability, or converged but did not meet, indicating that N was important but did not explain the whole difference. Where there was no interaction between rotation and N rate the response curves were parallel. The type of response could not be predicted. It was not profitable to apply N fertiliser to wheat in the PW rotation in 11 of the 17 trials. The average yield advantage of PW over WW, in the absence of N was 540 kg/ha, while there was an average increase of 1.7% grain protein.

Response of field peas to phosphate fertilization

2003 ◽  
Vol 83 (2) ◽  
pp. 283-289 ◽  
Author(s):  
R. E. Karamanos ◽  
N. A. Flore ◽  
J. T. Harapiak
Keyword(s):  
Uniform Design ◽  
Monoammonium Phosphate ◽  
Canadian Prairie ◽  
Yield Increase ◽  
Seed Moisture ◽  
Field Peas ◽  
Triple Super Phosphate ◽  
Seed Placement ◽  
P Application ◽  
The Impact

Canadian Prairie Provinces in general, and Saskatchewan in particular are major producers of peas worldwide. Individual provincial criteria for P application are considerably different from each other. Further introduction of new pea varieties and the adoption of direct seeding practices prompted us to re-evaluate these criteria. To this end, two experiments with field peas (Pisum sativum L. var. Carneval) were carried out between 1994 and 1998 at nine different locations in Alberta. The first experiment was carried out in 1994 and consisted of three trials with six rates of P (0, 4.4, 8.7, 13, 17.5 and 21.8 kg P ha-1) in the form of monoammonium phosphate (MAP) (12-51-0). To eliminate the impact of varying N rates along with P, a series of 21 trials and a uniform design that included five rates of P (0, 6.5, 13, 19.5 and 26 kg ha-1) in the form of triple super phosphate (0-45-0) and two methods of placement (seed placement or side banding) were subsequently carried out. There was a significant response to P application at all 13 sites of both experiments that contained 10 or less mg of a Modified Kelowna (MK) extractable-P kg-1 of soil. Side banding resulted in significantly higher yield in only three trials. Maximum average yield increase of 645 kg seed ha-1 was obtained with application of 19.5 kg P ha-1; it was influenced by soil texture as the magnitude of response was greater on loamy (535 kg seed ha-1) than on clay loam soils (285 kg seed ha-1). There was no significant yield increase in the trials that contained greater than 10 mg MK-P kg-1 soil. Reduction in plant population was more frequent as a result of seed placement (nine cases with P < 0.1) than side banding in both experiments. The impact of P fertilization on seed moisture was not consistent. The ability to side band or to seed with an increased seed bed utilization may fulfil the need for application of greater rates of P than the ones currently recommended for prairie soils. Key words: Seed placement, side banding, triple super phosphate, monoammonium phosphate

The Dynamic Response of a Simple Elastic System to Antisymmetric Forcing Functions Characteristic of Airplanes in Unsymmetric Landing Impact

1949 ◽  
Vol 16 (3) ◽  
pp. 310-316
Author(s):  
Joseph B. Woodson
Keyword(s):  
Dynamic Response ◽  
Sine Wave ◽  
Response Curves ◽  
Response Factors ◽  
Natural Period ◽  
Wave Pulse ◽  
Pulse Disturbance ◽  
Landing Impact ◽  
Forcing Functions ◽  
The Difference

Abstract This paper presents an analysis of the dynamic response of an undamped mechanical system with one degree of freedom subjected to disturbances which are described by antisymmetric forcing functions. The analysis was undertaken to throw light on the effect on the vibration of the wings caused by unsymmetric landing impact of an airplane. Two types of disturbances are considered; a full-sine-wave pulse, and a pulse which is the difference between two overlapping half sine waves. The results are presented in the form of dynamic-response curves and dynamic-response-factor curves. The numerically greatest dynamic-response factors, approximately 3.24 and −3.26, resulted for a full-sine-wave pulse disturbance with a ratio of duration of impact to natural period, Ti/T ≅ 1.11. When Ti/T is in the neighborhood of 1, the first positive peak of dynamic response is numerically less than the negative and positive peaks which follow it. For much of the range, the positive and negative dynamic-response factors are numerically approximately equal. The analysis was confined to values of Ti/T between 0.33 and 12. As Ti/T increases without limit, the positive and negative dynamic-response factors tend to 1 and −1, respectively.

Log-Logistic Analysis of Herbicide Dose-Response Relationships

1995 ◽  
Vol 9 (2) ◽  
pp. 218-227 ◽  
Author(s):  
Steven S. Seefeldt ◽  
Jens Erik Jensen ◽  
E. Patrick Fuerst
Keyword(s):  
Dose Response ◽  
Logistic Model ◽  
Response Analysis ◽  
Analysis Method ◽  
Weed Science ◽  
Response Curves ◽  
Herbicide Resistant ◽  
Logistic Analysis ◽  
Analysis Methods ◽  
The Difference

Dose-response studies are an important tool in weed science. The use of such studies has become especially prevalent following the widespread development of herbicide resistant weeds. In the past, analyses of dose-response studies have utilized various types of transformations and equations which can be validated with several statistical techniques. Most dose-response analysis methods 1) do not accurately describe data at the extremes of doses and 2) do not provide a proper statistical test for the difference(s) between two or more dose-response curves. Consequently, results of dose-response studies are analyzed and reported in a great variety of ways, and comparison of results among various researchers is not possible. The objective of this paper is to review the principles involved in dose-response research and explain the log-logistic analysis of herbicide dose-response relationships. In this paper the log-logistic model is illustrated using a nonlinear computer analysis of experimental data. The log-logistic model is an appropriate method for analyzing most dose-response studies. This model has been used widely and successfully in weed science for many years in Europe. The log-logistic model possesses several clear advantages over other analysis methods and the authors suggest that it should be widely adopted as a standard herbicide dose-response analysis method.

Clearance and Dry Friction Study in a Nonlinear Torsional Vibration of a Rotating Machinery

1999 ◽  
Author(s):  
Kazuki Mizutani ◽  
Hossain Md. Zahid
Keyword(s):  
Torsional Vibration ◽  
Dry Friction ◽  
Friction Torque ◽  
Frictional Property ◽  
Behavioral Characteristics ◽  
Spring Stiffness ◽  
Response Curves ◽  
Friction Models ◽  
The Difference ◽  
Friction Study

Abstract Clearance problem in coupling is often experienced in a rotary torsional vibration system. We tried to analyze the qualitative and quantitative characteristics of torsional vibration by modeling the bilinear spring stiffness with changing friction torque. Symmetric and asymmetric spring stiffness with friction models are developed to investigate the behavioral characteristics of the system for simulations and experiments. The frequency response curves and time response curves with external sinusoidal excitation are observed by several non-dimensional numerical simulations. The thoroughly experiments are done to understand the actual phenomena of torsional vibration, verification of models and adjustability of simulations. The frictional property considered as dry friction in coupling is found very significant parameter to reduce the vibration within a tolerable range in both of the simulations and experiments. The difference between the results getting from simulations and experiments are also demonstrated in this paper elaborately.

Productivity of crops grown on raised beds on duplex soils prone to waterlogging in Western Australia

2007 ◽  
Vol 47 (11) ◽  
pp. 1368 ◽  
Author(s):  
D. M. Bakker ◽  
G. J. Hamilton ◽  
D. J. Houlbrooke ◽  
C. Spann ◽  
A. Van Burgel
Keyword(s):  
Grain Yield ◽  
Western Australia ◽  
Arable Land ◽  
Experimental Period ◽  
Grain Yields ◽  
Yield Increase ◽  
Field Peas ◽  
Yield Difference ◽  
Raised Bed ◽  
Flat Ground

Waterlogging of duplex soils in Western Australia has long been recognised as a major constraint to the production of agricultural crops and pastures. The work described in this paper examines the application of raised beds to arable land that is frequently waterlogged for the production of crops such as wheat, barley, field peas, lupins and canola. Raised beds are 138 cm wide, seed beds separated by 45 cm wide furrows 183 cm apart. These beds were made with a commercial bed former. Seven sites were selected across the south-eastern wheat belt of Western Australia with the experimental areas varying in size from 10 to 57 ha. These large sites were used to accommodate commercial farm machinery. Each site had raised beds formed with a commercial bedformer. The production from the bedded areas was compared with crops grown conventionally on flat ground under minimum tillage as the control. The experiments were established in 1997 and 1998 and the sites were monitored for a maximum of 5 years. In 11 of the 28 site-years of the experiments, grain yields on the raised beds were statistically significantly higher than the yield from crops grown on the control, with an average yield increase of 0.48 t/ha. Across the whole dataset, growing crops on raised beds did not produce significantly lower yields. Below average rainfall was received for much of the experimental period at several sites. Growing season rainfall had a large effect on grain yield and high rainfall over a period of 40 days after seeding significantly increased the grain yield difference between the raised bed and the control. These data indicate that the use of raised beds lead to higher grain yields when seasonal conditions are appropriate.

scholarly journals Effect of Site Specific Nitrogen Management on Seed Nitrogen—A Driving Factor of Winter Oilseed Rape (Brassica napus L.) Yield

Agronomy ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1364 ◽  
Author(s):  
Remigiusz Łukowiak ◽  
Witold Grzebisz
Keyword(s):  
Oilseed Rape ◽  
Field Experiments ◽  
Winter Oilseed Rape ◽  
Brassica Napus L ◽  
N Accumulation ◽  
Yield Increase ◽  
N Supply ◽  
Site Diversity ◽  
Rate Interaction ◽  
N Pool

It has been assumed that the management of both soil and fertilizer N in winter oilseed rape (WOSR) is crucial for N accumulation in seeds (Nse) and yield. This hypothesis was evaluated based on field experiments conducted in 2008/09, 2009/10, 2010/11 seasons, each year at two sites, differing in soil fertility, including indigenous N (Ni) supply. The experimental factors consisted of two N fertilizers: N and NS, and four Nf rates: 0, 80, 120, 160 kg ha−1. Yield, as governed by site × Nf rate interaction, responded linearly to Nse at harvest. The maximum Nse (Nsemax), as evaluated by N input (Nin = Ni + Nf) to WOSR at spring regrowth, varied from 95 to 153 kg ha−1, and determined 80% of yield variability. The basic reason of site diversity in Nsemax was Ni efficiency, ranging from 46% to 70%, respectively. The second cause of Nse variability was a shortage of N supply from + 9.5 soil to −8.8 kg ha−1 to the growing seeds during the seed filling period (SFP). This N pool supports the N concentration in seeds, resulting in both seed density and a seed weight increase, finally leading to a yield increase.

Metabolic Responses to Thermal Stressors of Altitude-Acclimated Rats

1958 ◽  
Vol 195 (3) ◽  
pp. 739-743 ◽  
Author(s):  
Henry B. Hale ◽  
Roy B. Mefferd
Keyword(s):  
Urine Volume ◽  
Temperature Response ◽  
Ground Level ◽  
Metabolic Responses ◽  
Control Group ◽  
Response Curves ◽  
Level Pressure ◽  
Metabolic Functions ◽  
Per Se ◽  
The Difference

Fasting 24-hour exposures of altitude-acclimated rats (380 mm Hg, 18,000 ft. simulated) to ground level pressure (750 mm Hg) at either cold (3°C), neutral (24°C), or hot (35°C) temperatures seldom resulted in return of their metabolic functions to preacclimative ‘normalcy.’ Although the control and altitude-acclimated groups both were accustomed to neutral temperatures (24° and 26°C), quantitative differences at ground level and altitude occurred in various indices of water, mineral and nitrogen metabolism. Of the 32 physiologic variables studied, only 4 (ratio of urine volume/ water intake, and urinary excretion of potassium, creatinine and glycine) failed to differentiate the responses of the altitude- and ground-accustomed rats. The temperature response curves of the altitude group tended to parallel the corresponding ones for the control group, but most variables were on higher or lower planes. The difference in plane resulted either from the effects of the return to ground level pressure, or from nonreversible effects of acclimation to altitude per se.

scholarly journals Environment-specific selection to identify high yielding wheat genotypes and response to fungicide application

Revista CERES ◽  
2017 ◽  
Vol 64 (2) ◽  
pp. 167-175 ◽  
Author(s):  
Giovani Benin ◽  
Lindolfo Storck ◽  
Volmir Sergio Marchioro ◽  
Elesandro Bornhofen ◽  
Leomar Guilherme Woyann ◽  
...  
Keyword(s):  
Triticum Aestivum L ◽  
Control Treatment ◽  
Environment Interaction ◽  
Yield Data ◽  
Wheat Genotypes ◽  
Fungicide Application ◽  
Year Effect ◽  
The Difference ◽  
And Control ◽  
All Diseases

ABSTRACT Selection of disease resistant genotypes is the main goal of wheat (Triticum aestivum L.) breeding programs. However, because of the lack of genotypes resistant to all diseases and the strong influence of the environment on the level of resistance of the genotypes, the use of fungicides is necessary in the cultivation of wheat. The objective of this study was to compare the gain in yield and the selection efficiency of wheat genotypes due to the fungicide application in trials carried out in different sites and years. This study used grain yield data from 816 wheat genotypes evaluated in 248 advanced trials at eight sites during the years from 2004 to 2012. The gain resulting from fungicide application for a given genotype was estimated by the difference between yield of plots on which fungicide was applied and control treatment. The greatest gains with fungicide application were observed in sites with lower average temperatures and higher rainfall indices, such as Campo Mourão, Castro, Não-Me-Toque and Guarapuava. On the other hand, the lowest gains with fungicide application occurred in Dourados and Palotina, environments where crops in general suffer water stress and present higher average temperatures. The year effect resulted in yield increases due to fungicide application ranging from 16.9 to 60.7%. The selection and evaluation of the response to the application of fungicide in wheat should be environment-specific to maximize the use of genotype x environment interaction.

Adenosine participates in regulation of smooth muscle relaxation in aortas from rats with experimental hypothyroidism

2002 ◽  
Vol 80 (6) ◽  
pp. 507-514 ◽  
Author(s):  
G Baños ◽  
F Martínez ◽  
J I Grimaldo ◽  
M Franco
Keyword(s):  
Smooth Muscle ◽  
Adenosine Receptor ◽  
Adenosine Receptors ◽  
Muscle Relaxation ◽  
Rat Aorta ◽  
Smooth Muscle Relaxation ◽  
Vascular Relaxation ◽  
Response Curves ◽  
The Difference ◽  
The Right

The contribution of adenosine receptors was evaluated in vascular relaxation in experimental hypothyroidism. Hypothyroid aortic rings contracted less than normal controls with noradrenaline, phenylephrine, and KCl; the difference was maintained after incubation with 1,3-dipropyl-8-p-sulfophenylxanthine (an A1 and A2 adenosine receptor blocker). The vascular relaxation induced by acetylcholine or carbachol was similar in normal and hypothyroid aortic rings. However, adenosine, N6-cyclopentyladenosine (an A1 adenosine receptor analogue), and 5'-N-ethylcarbox amidoadenosine (an A2 and A3 adenosine analogue) induced vasodilation that was larger in hypothyroid than in normal aortas. Nω-nitro-L-arginine methyl ester shifted the dose-response curves of adenosine, N6-cyclopentyladenosine, or 5'-N-ethylcarboxamidoadenosine to the right in both normal and hypothyroid vessels. The blocker 1,3-dipropyl-8-p-sulfophenylxanthine significantly reduced adenosine-induced relaxation in the hypothyroid but not in the normal aortic vessels. These results suggest that in hypothyroid aortas, a larger adenosine-mediated vasodilation is observed probably due to an increase in receptor number or sensitivity.Key words: adenosine receptors, nitric oxide, hypothyroidism, smooth muscle, rat aorta.

The ecology of Ramalina menziesii. VI. Laboratory responses of net CO2 exchange to moisture, temperature, and light

1987 ◽  
Vol 65 (1) ◽  
pp. 182-191 ◽  
Author(s):  
U. Matthes-Sears ◽  
T. H. Nash III ◽  
D. W. Larson
Keyword(s):  
Dark Respiration ◽  
Net Photosynthesis ◽  
Co2 Exchange ◽  
Response Curves ◽  
Central California ◽  
Photosynthetic Rates ◽  
Chlorophyll Contents ◽  
The Mean ◽  
The Difference ◽  
Thallus Water Content

The response of net CO2 exchange to thallus water content, thallus temperature, and photosynthetically active radiation was measured in the laboratory for two morphologically different forms of Ramalina menziesii collected from a coastal and an inland habitat in central California. Equations describing the response curves are fitted to the data and compared statistically for the two sites during two seasons. Significant differences were present for all responses both in summer and winter but were more pronounced for net photosynthesis than for dark respiration. The main differences between the two forms were in the absolute rates of net photosynthesis; a maximum of 6.2 was measured for the inland form but only 3.6 mg∙g−1∙h−1 for the coastal form. Chlorophyll contents were also different between the two forms, indicating that chlorophyll is the likely cause for the difference in net photosynthetic rates. Net photosynthetic rates were higher at low temperatures during winter than during summer, but otherwise seasonal variations in the gas exchange responses were relatively minor. Both forms of the lichen are light saturated at quantum fluxes greater than 200 μE∙m−2∙s−1. Both show an optimum temperature for maximum CO2 exchange at 25 °C, well above the mean operating temperature of R. menziesii in the field.

Sign in / Sign up

Export Citation Format

Share Document