scholarly journals Evaluation of the performance of three advisory methods for nitrogen fertilization of sugar beet and potatoes.

1989 ◽  
Vol 37 (2) ◽  
pp. 143-155 ◽  
Author(s):  
J.J. Neeteson
Keyword(s):  
Crop Yields ◽  
Current Method ◽  
Early Spring ◽  
The Other ◽  
Fertilizer N ◽  
Potato Tubers ◽  
Current Recommendation ◽  
Mineral N ◽  
Fertilizer Recommendation ◽  
The Difference

The performances of 3 different N fertilizer recommendation methods were retrospectively tested with data obtained from 150 trials with sugarbeet and 98 trials with potatoes in the Netherlands in 1973-82. The recommendations consisted of applying a fixed N rate in all situations (126 kg N/ha for sugarbeet and 286 kg N/ha for potatoes), the current Dutch method, which takes only the amount of mineral N present in the soil in early spring into account, and a refinement of the current method, which also takes soil type and recent applications of organic manures into account. On av., significantly lower amounts of fertilizer N were recommended with the current method. The difference from the other methods was on av. 25 kg N/ha for sugarbeet and 30 kg N/ha for potatoes. With the refined current method the highest crop yields were obtained but the difference from the other methods was not significant and averaged only 0.3-0.4 t/ha for sugarbeet and 0.1-0.2 t/ha for potatoes. The recovery of fertilizer N by the potato tubers was 2% higher with the current method than with the other methods. Based on these findings it is concluded that the current recommendation method is preferable to the other methods. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Influence of sowing date on the uptake of and responses to soil and fertilizer nitrogen by the spring wheat cultivar Tonic

1995 ◽  
Vol 125 (1) ◽  
pp. 25-37 ◽  
Author(s):  
J. Webb ◽  
R. Sylvester-Bradley ◽  
J. D. Wafford
Keyword(s):  
Grain Yield ◽  
Spring Wheat ◽  
Sowing Date ◽  
N Recovery ◽  
Fertilizer N ◽  
Mineral N ◽  
Optimum Yield ◽  
Sowing Dates ◽  
The Difference ◽  
The Uk

SUMMARYAt 14 sites in the UK, spring wheat (Triticum aestivum) cv. Tonic, was sown on three or four dates at each site between October and March in the 1988/89, 1989/90 and 1990/91 seasons. Responses to spring-applied fertilizer N over the range 0–320 kg/ha were determined. Earlier sowing did not increase uptake of soil N by the crop. Fertilizer N increased grain N offtake by between 25 and 140 kg/ha and yield by between 0·3 and 5·5 t/ha, although grain yield was less responsive to fertilizer N at later sowing dates. Apparent recovery of fertilizer N (AFR) also decreased as sowing was delayed but there was no effect of delayed sowing on the amount of grain produced from each kg of fertilizer N recovered. Because fertilizer N recovery decreased with later sowing, the amount of fertilizer N needed to produce the optimum economic grain yield was not reduced. Neither AFR nor optimum fertilizer (Nopt) was related to optimum yield. Regression of Nopt on the difference between optimum yield and yield without fertilizer N (△y) explained 77% of the variance in Nopt. There was an inverse relationship between △y and soil mineral N (SMN) in spring; regression of △y, on SMN in spring accounted for 29% of the variance in △y Current advisory systems which adjust economic fertilizer N recommendations according to anticipated yield are not justified by these results. Moreover the adjustments made, based on yield expectation, appear about three times as large as those needed to minimize residues of fertilizer N left unrecovered by the crop and to reduce the risk of nitrate leaching in the following winter.

scholarly journals Modeling the Recommendation of Nutrients for Cabbage (Brassica oleracea) Crop

2019 ◽  
Vol 11 (7) ◽  
pp. 220
Author(s):  
Thaísa Fernanda Oliveira ◽  
Leonardo Angelo de Aquino ◽  
Maria Elisa Paraguassu Soares ◽  
Talita Gabriela Gentil ◽  
Flávio Lemes Fernandes ◽  
...  
Keyword(s):  
Brassica Oleracea ◽  
Crop Residues ◽  
Nutrient Supply ◽  
The Other ◽  
Balance Model ◽  
Recovery Efficiency ◽  
Fertilizer Recommendation ◽  
Productive Potential ◽  
The Difference ◽  
Nutritional Balance

Cabbage presents high nutrients demand, which requires proposal of recommendation models that are compatible with current productive potential. The objective of this study was to propose a nutritional balance model to recommend nutrients for cabbage. In order to estimate fertilizer recommendation, the system considered the requirement subsystem (REQ), which includes the crop demand and recovery efficiency (RE) of the applied nutrient, and supply subsystem (SUP), which corresponds to the nutrient supply by soil and crop residues. To determine the attributes needed to estimate nutritional demand, values were obtained from literature and from two experiments, one with nitrogen (N) and one with potassium (K). The fertilizer recommendation for N, P and K consisted in the difference between REQ and SUP. For the other nutrients, the system presented only crop export and extraction and not the REQ due to scarcity of data regarding RE. The modeling is a useful tool for recommending fertilization for cabbage and is subject to constant improvements.

scholarly journals An analysis of the response of sugar beet and potatoes to fertilizer nitrogen and soil mineral nitrogen.

1989 ◽  
Vol 37 (2) ◽  
pp. 129-141 ◽  
Author(s):  
J.J. Neeteson ◽  
H.J.C. Zwetsloot
Keyword(s):  
Soil Type ◽  
Field Trials ◽  
Soil Mineral N ◽  
Fertilizer N ◽  
Soil Mineral ◽  
Soil Mineral Nitrogen ◽  
Mineral N ◽  
Organic Manures ◽  
The Difference ◽  
Prior Application

A statistical analysis was performed to investigate if, and to what extent, the response of sugarbeet and potatoes to fertilizer N depended on the amount of mineral N already present in the soil, soil type, and prior application of organic manures. For this purpose the results of 150 field trials with sugarbeet and 98 with potatoes were used. The analysis was focussed on the within-block stratum of variation in yield, where regression models were fitted to describe the response to N. For both sugarbeet and potatoes the best fit was obtained when not only fertilizer N was taken into account, but also soil mineral N, soil type and prior application of organic manures. The response to fertilizer N was weaker as the amount of soil mineral N was larger. The optimum amount of fertilizer N plus soil mineral N required was larger on sandy soils than on loam and clay soils. The difference was about 20 kg N/ha for sugarbeet and 100 kg N/ha for potatoes. When organic manures were applied prior to the application of fertilizer N, the optimum for both sugarbeet and potatoes was 15-50 N/ha lower than without application of organic manures. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Nutrient Expert for High Yield and Use Efficiency in Rainfed Bt Cotton Hybrids

2021 ◽  
Vol 3 ◽  
Author(s):  
Angamuthu Manikandan ◽  
Desouza Blaise ◽  
Sudarshan Dutta ◽  
T. Satyanarayana ◽  
Bhargavi Bussa
Keyword(s):  
Nutrient Uptake ◽  
Crop Yields ◽  
Insect Pests ◽  
Nutrient Balance ◽  
Central India ◽  
The Other ◽  
Utilization Efficiency ◽  
High Yield ◽  
Bt Cotton ◽  
Fertilizer Recommendation

Low cotton productivity in the rainfed cotton grown in central India is attributed to abiotic (water and nutrients) and biotic (insect pests and diseases) stress. Nutrient stress can be overcome by providing nutrients in right amounts and at the right time when the plant needs the most. Field studies in cereal crops have demonstrated fertilizer recommendations by using the Nutrient Expert® (NE) decision support system to improve crop yields. However, such information in the case of the commercial crop, cotton, is scarce. Therefore, on-farm trials were conducted in three districts of Maharashtra, India during 2018–2020 with the hypothesis that the NE-based fertilizer recommendation would lead to higher cotton productivity and savings in fertilizer. Averaged over two seasons and locations, lint yield was significantly greater in the NE based than the recommended dose of fertilizer (RDF), soil test crop response (STCR), and farmers' practice (FP). Internal utilization efficiency (IE) did not differ among treatments for N (4.8 to 5.9 kg lint kg−1 nutrient uptake) and K (6.7 to 7.2 kg lint kg−1 nutrient uptake). With regard to the fertilizer P applied, the FP treatment had the least IE (17.0 kg lint kg−1 nutrient uptake) and was significantly lower than the other treatments. Partial nutrient balance (PNB) did not vary among treatments for applied fertilizer N. The FP treatment had PNB < 1 in case of fertilizer P and ~20 in the case of fertilizer K. This indicates farmers applied excess of P fertilizers. On the other hand, farmers in the region applied very small amount of K. Although the NE treatment had the highest cost of cultivation, net returns were the greatest followed by the STCR and RDF treatments. Our studies demonstrate that the NE-based fertilizer recommendation is not only productive, but also profitable.

Investigations in crop husbandry. II. On the age of seed beans

1935 ◽  
Vol 25 (3) ◽  
pp. 361-368
Author(s):  
F. H. Garner ◽  
H. G. Sandees
Keyword(s):  
Field Experiments ◽  
Early Spring ◽  
The Other ◽  
Large Seed ◽  
Other Hand ◽  
Crop Husbandry ◽  
The Difference ◽  
Different Strains

1. New and old seed beans have been compared for three years, in the last two of which precise field experiments have been conducted with two different strains.2. In general new seed gave higher yields than old seed, but the difference was only of the order of 10 per cent. There was some evidence that conditions when the seed was harvested might be more important than age.3. New seed produced more branches in early spring, and a greater number of pod-bearing stems at harvest; on the other hand, old seed produced stems that were more thickly podded at harvest, and pods that contained a greater number of beans.4. In one case abnormally large seed produced very vigorous plants, and very large beans at harvest.

Interférence du chénopode blanc (Chenopodium album), chez l'avoine et la luzerne : seuils de nuisibilité

1984 ◽  
Vol 62 (12) ◽  
pp. 2594-2599 ◽  
Author(s):  
Anne-Marie Lapointe ◽  
Jean-Marc Deschênes ◽  
Paul Gervais ◽  
Claudel Lemieux
Keyword(s):  
Soil Type ◽  
Crop Yields ◽  
Chenopodium Album ◽  
Growth Conditions ◽  
The Other ◽  
Vegetative Stage ◽  
Close Relationship ◽  
Negative Effect ◽  
The Difference ◽  
Number Of Individuals

The competitive threshold of Iamb's-quarters (Chenopodium album L.) in alfalfa and oats was studied in the greenhouse and in the field. In oats, the competitive threshold of Iamb's-quarters was reached at a density of 1000 plants/m2 in the field. In the greenhouse, the weed could not compete with oats when both were sown simultaneously. When Iamb's-quarters was sown 15 days earlier than oats, crop yields were significanty reduced under a density of 800 plants/m2. The competitive threshold of Iamb's-quarters in alfalfa was reached at a density of 200 plants/m2 in the greenhouse and 1000 plants/m2 in the field. The difference between the results of the two experiments was mainly caused by the growth conditions (soil type, fertility, humidity) which were quite different and influenced both the weed and the crop. Two harvest treatments were compared and it seems preferable to take the first cut of alfalfa at the 10% bloom stage rather than at the vegetative stage. A cut taken at the vegetative stage had a negative effect on alfalfa. This effect did not seem related to the weed but rather to a weakening of the legume. A close relationship existed between the number of individuals per square metre and the biomass of Iamb's-quarters, on one hand, and the yield of alfalfa or oats, on the other hand. The classes of Iamb's-quarters with the largest densities, or the highest biomass, were the most competitive.

scholarly journals Transformation of Nitrogen Fertilizers in Greenhouse Experiments

2002 ◽  
Vol 51 (1-2) ◽  
pp. 147-156 ◽  
Author(s):  
Erika Nótás ◽  
K. Debreczeni ◽  
K. Fischl ◽  
Keyword(s):  
Soil Moisture ◽  
Difference Method ◽  
N Uptake ◽  
First Year ◽  
Fertilizer N ◽  
Plant N Uptake ◽  
Mineral N ◽  
After Effect ◽  
Gaseous Loss ◽  
The Difference

The primary (1 st year) and the after-effects (2 nd , 3 rd year) of N fertilizers (KNO 3 , NH 4 Cl) on the soil-plant-atmosphere system were studied in a three-year greenhouse pot experiment with and without maize plants. The two- and three-year balances of the fertilizer N uptake and gaseous N losses were also analyzed. The cumulative values of the gaseous losses showed a similar trend in all years, significant differences were not obtained. On the basis of the three-year balance, the gaseous loss in the planted and unplanted pots was 18-22% and about 37-39%, respectively. Consequently, there was a 50% decrease in denitrificated gaseous losses of fertilizer N due to plant N uptake. The cumulative gaseous loss, calculated by the difference method, was significantly higher in cases of KNO 3 applications than in NH 4 Cl treatments, as an assumed  consequence of the intensive denitrification. It was found that the gaseous loss was not influenced by soil moisture.  In contrast to the gaseous losses, the values of plant N uptake and soil mineral N content showed significant differences in the years studied, as a result of the quick transformation of mineral N to organic N, the non-complete homogenization of the total soil amount, the seasonal climatic differences in the greenhouse during the years studied, and consequently the different microbiological activity. The plant N uptake was found to depend significantly on the fertilizer N form. Results obtained by the difference method and the 15 N-tracer technique were very similar. In the case of KNO 3 treatment and higher soil moisture (WHC = 80%) plant N uptake was more intensive, ranging between 48-57% (calculated by the difference method), and 35-51% (calculated by the 15 N- tracer method) in the first year (1993). It can be concluded that 60-100% of the fertilizer N was used from the soil by plant uptake and gaseous losses, which depends mainly on the treatments and the soil moisture during the first year. These values changed between 7-17% in the 1 st year after-effect and between 1-5% in the 2 nd year after-effect.

Enhancement of ADP-induced Platelet Aggregation by Adrenaline in Vivo and Its Prevention

1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Endothelial Surface ◽  
Important Interaction ◽  
Blood Coagulability ◽  
The Difference

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

Energy Approximation

2017 ◽  
Author(s):  
Philip Isett
Keyword(s):  
Main Lemma ◽  
The Other ◽  
Coarse Scale ◽  
Continuous Solutions ◽  
Material Derivative ◽  
Energy Variation ◽  
Energy Approximation ◽  
The Difference ◽  
Derivatives Of

This chapter presents the equations and calculations for energy approximation. It establishes the estimates (261) and (262) of the Main Lemma (10.1) for continuous solutions; these estimates state that we are able to accurately prescribe the energy that the correction adds to the solution, as well as bound the difference between the time derivatives of these two quantities. The chapter also introduces the proposition for prescribing energy, followed by the relevant computations. Each integral contributing to the other term can be estimated. Another proposition for estimating control over the rate of energy variation is given. Finally, the coarse scale material derivative is considered.

Pengaruh Unsur Budaya Lokal dalam Ungkapan Berbahasa Perancis

Metahumaniora ◽  
2017 ◽  
Vol 7 (3) ◽  
pp. 378
Author(s):  
Vincentia Tri Handayani
Keyword(s):  
Mental Representation ◽  
Cultural Context ◽  
Oral Tradition ◽  
Minimal Element ◽  
The Other ◽  
Local Culture ◽  
Community Groups ◽  
Cultural Community ◽  
The Difference ◽  
Complex Words

AbstrakFolklor yang menghasilkan tradisi lisan merupakan perwujudan budaya yang lahirdari pengalaman kelompok masyarakat. Salah satu bentuk tradisi lisan adalah ungkapan yangmengandung unsur budaya lokal dalam konstruksinya yang tidak dimiliki budaya lainnya.Ungkapan idiomatis memberikan warna pada bahasa melalui penggambaran mental. Dalambahasa Perancis, ungkapan dapat berupa locution dan expression. Perbedaan motif acuansuatu ungkapan dapat terlihat dari pengaruh budaya masyarakat pengguna bahasa. Sebuahleksem tidak selalu didefinisikan melalui unsur minimal, tidak juga melalui kata-kata,baik kata dasar atau kata kompleks, namun dapat melalui kata-kata beku yang maknanyatetap. Hubungan analogis dari makna tambahan yang ada pada suatu leksem muncul dariidentifikasi semem yang sama. Semem tersebut mengarah pada term yang diasosiasikan danyang diperkaya melalui konteks (dalam ungkapan berhubungan dengan konteks budaya).Kata kunci: folklor, ungkapan, struktur, makna idiomatis, kebudayaanAbstractFolklore which produces the oral tradition is a cultural manifestation born out theexperience of community groups. One form of the oral tradition is a phrase that containsthe elements of local culture in its construction that is not owned the other culture. Theidiomatic phrase gives the color to the language through the mental representation. InFrench, the expression can consist of locution and expression. The difference motivesreference of an expression can be seen from the influence of the cultural community thelanguage users. A lexeme is not always defined through a minimal element, nor throughwords, either basic or complex words, but can be through the frost words whose meaningsare fixed. The analogical connection of the additional meanings is on a lexeme arises fromthe identification of the same meaning. The meaning ‘semem’ leads to the associated termsand which are enriched through the context (in idiom related to the cultural context).Keywords : folklore, idioms, structure, idiom meaning, cultureI PENDAHULUAN

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