The effect of salinity on corn yield using the CERES-maize model     

José Beltrão  Jiftah Ben Asher 《Irrigation and Drainage Systems》1997,11(1):15-28

In most cases, when calculating soil water availability, only thewater content is considered. The effect of salinity on the wiltingpoint is neglected. The objective of this work is to use asimulation model (CERES-maize) in order to predict cornyields as a function of water salinity under severalenvironmental, agrotechnical, and plant characteristics. A modelis presented in which the wilting point is a function of the soilsalt content. At high salinity, the water content at wilting pointis higher than at low salinity, resulting in an insufficient amountof available water and, therefore, a reduced yield. The modelwas used to simulate several theoretical and experimentalsituations for forage corn and grain corn. Simulation resultsshowed that nitrogen fertilization increases the salinity thresholdvalue and the yield sensitivity (rate of yield reduction per unitof salinity). The also showed that forage corn is more sensitiveto salinity than grain corn. If the soil is not leached, a heaviersoil texture has a higher salinity threshold value. On the otherhand, if the soil is leached, the soil texture has no influence onthe salinity threshold value and the yield is less sensitive tosalinity in sandy soils. The determination coefficient (r²= 0.75) indicated that the results of the simulations were in goodagreement with the field data.  相似文献   

Simulated water and solute distribution from a crossed triple line-source     

D. A. Magnusson  J. Ben Asher 《Irrigation Science》1990,11(1):31-36

Summary Multivariable irrigation experiments are usually expensive and seldom cover the whole range of desired values. The crossed triple line-source (CTLS) was designed to provide a relatively simple and inexpensive irrigation system for creating continuous gradients of more than one variable. A computer model was developed to assist in evaluating the continuously changing multivariable levels, produced by the CTLS, given various inputs. A single sprinkler's distribution function was used in the model's development. The results of the overlapping sprinkling patterns are calculated throughout the experimental area for water depth, salinity level, and Nitrogen concentration. Measured values of irrigation water electrical conductivity (EC_i) and Nitrogen concentration were in good agreement with predicted values.  相似文献   

Erratum to “Application of treated wastewater for cultivation of roses (Rosa hybrida) in soil-less culture” [Sci. Hortic. 108 (2006) 185–193]     

Nirit Bernstein  Asher Bar-Tal  Haya Friedman  Pini Snir  Ilona Rot  Amram Chazan  Marina Ioffe 《Scientia Horticulturae》2007

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Clinical and pathological findings of Babesia infection in dogs   总被引：1，自引：0，他引：1  

PJ IRWIN  GW HUTCHINSON 《Australian veterinary journal》1991,68(6):204-209

The clinical and pathological findings of Babesia infection in 32 dogs in northern Australia are presented. Eleven different breed types were represented from 6 localities in north Queensland and one locality in northern Western Australia. Twenty three (72%) were males. Babesia-infected dogs were grouped by the degree of haematological disturbance and clinical severity: Acute babesiosis (25/32), all pups with severe haemolytic anaemia; subclinical carriers (5/32) with non-specific malaise, characterised haematologically by a normal erythrogram but marked leucopenia; chronic anaemia, observed in 2 adult dogs. Pups were azotaemic (serum urea greater than 6.6 mmol/l) and had elevated serum bilirubin levels (20.8 to 48.5 mmol/l). Total serum protein was usually within the normal range. Pups that died were also hypoglycaemic and severely hyperkalaemic (K+ greater than 10 mmol/l). Low parasitaemias in routine blood smears complicated diagnosis but smears made from ear or toe capillaries, or after haematocrit concentration, greatly enhanced finding parasitised cells. At necropsy, pallor and jaundice were the most consistent observations. Haemoglobinuric nephrosis, an active reticulo-endothelial system and capillaries packed with large numbers of infected erythrocytes were the main histopathological findings. A combination of imidocarb dipropionate at 5 mg/kg body weight, given intramuscularly, with fluid therapy and blood transfusion was the most successful treatment.  相似文献   

Suspected Cryptostegia grandiflora (rubber vine) poisoning in horses     

DR COOK  GW CAMPBELL  AR MELDRUM 《Australian veterinary journal》1990,67(9):344-344

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Creutzfeldt-Jakob disease (spongiform encephalopathy): transmission to the chimpanzee   总被引：48，自引：0，他引：48  

C J Gibbs  D C Gajdusek  D M Asher  M P Alpers  E Beck  P M Daniel  W B Matthews 《Science (New York, N.Y.)》1968,161(839):388-389

Biopsy material taken from the brain of a patient with CreutzfeldtJakob disease with status spongiosus induced a similar fatal encephalopathy in a chimpanzee 13 months after inoculation.  相似文献   

High bedload transport rates in relation to stream power Wadi Mikeimin,Sinai     

Asher P. Schick  Judith Lekach 《CATENA》1981,8(1):43-47

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An outbreak of fatal verminous pneumonia in cattle in north Queensland     

WL TOWNSEND  GW JONES  NP STEWART 《Australian veterinary journal》1992,69(9):231-231

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Raman spectroscopic evidence for two conformations of uncomplexed valinomycin in the solid state     

K J Rothschild  I M Asher  E Anastassakis  H E Stanley 《Science (New York, N.Y.)》1973,182(110):384-386

Raman spectroscopy is applied for the first time to elucidate the different conformations of the carrier transport molecule, valinomycin. Splitting of the ester and amide carbonyl stretch vibrations is observed in the Raman spectrum of crystals of valinomycin grown from both n-octane and acetone. These observations support the contention that some ester carbonyl groups are intramolecularly hydrogen bonded. The Raman spectrum of valinomycin grown from o-dichlorobenzene does not display this feature.  相似文献   

Recommendations of the International Roundtable Workshop on Bovine Spongiform Encephalopathy.     

C J Gibbs  C L Bolis  D M Asher  R Bradley  R W Fite  R T Johnson  B W Mahy  G M McKhann 《Journal of the American Veterinary Medical Association》1992,200(2):164-167

Recommendations of the working party were summarized as follows: Determine the status in all countries of their national cattle herds with respect to BSE. Attempt to develop a test to recognize BSE-infected animals before they become clinically ill. Establish procedures to prevent spread of BSE agent into the cattle populations, especially by eliminating feeds containing rendered ruminant proteins. Review the rendering processes, identify the sources and destinations of rendered products, and suggest appropriate changes if needed. Especially needed are standardized rendering procedures in regard to use of organic solvents, temperature, and duration of heat treatment. Review import and export regulations to reduce the risk of spreading BSE and to maximize opportunities for safe trading in cattle and cattle products. The scrapie-free certification program of the USDA was supported, and similar programs might be considered by other countries. If BSE/scrapie is diagnosed in a given country, determine baseline incidence of CJD in those countries and consider contributing to an international registry. The WHO should address the problems of BSE, formulate policy, participate in and coordinate research, and provide training opportunities for veterinary and human health care workers from eastern European countries and developing nations. Government and private agencies should consider increasing support for research on transmissibility and pathogenesis of CJD, BSE, CWD, scrapie, and transmissible mink encephalopathy. Prepare and publish a critical neuropathologic review of all spongiform encephalopathies, naturally and experimentally transmitted, defining the characteristics of each disease in the various species known to be susceptible. Consider producing guidelines for the biological and pharmaceutical industries with regard to sourcing, collecting, and processing bovine and ovine materials.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献