Pathogenesis of canine herpesvirus in specific-pathogen-free dogs: 5- to 12-week-old pups     

M J Appel  M Menegus  I M Parsonson  L E Carmichael 《American journal of veterinary research》1969,30(12):2067-2073

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Rubbery Rot (Oospora lactis (Fres.) Sacc.) of Potatoes     

U. R. Humphreys-Jones   《Plant pathology》1969,18(4):186-187

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FACTORS AFFECTING THE LOSS OF TRI-ALLATE FROM SOILS     

ALLAN E. SMITH 《Weed Research》1969,9(4):306-313

Summary. Electron-capture gas chromatography was used to detect tri-allate residues in persistence studies with two soils. At rates equivalent to 0–75, 15 and 3 Ib/ac, 50% of the amount applied was degraded in 8–11 weeks at 25°C in moist Regina heavy clay and Weyburn loam. No loss occurred in sterile soils, indicating that microbial degradation may be a, major factor contributing to tri-allate breakdown.
When aqueous solutions buffered at pH 4–8 were held at 25° G, only 10–15% of the tri-allate was chemically degraded during 24 weeks.
At the normal field rate of 1·25 Ib/ac, tri-allate was not readily leached. From soil columns of Weyburn loam, 5–7% was eluted by 9 in. of water; with clay the corresponding value was 12–13% of the amount applied. When field plots were sprayed with 125 lb/ac in April, tri-allate could still be detected until the soil froze in November.
Facteurs agissant sur la perte de tri-allate dans les sots  相似文献   

TRANSLOCATION OF AMINOTRIAZOLE AND DALAPON IN AG ROPY RON REPENS (L.) BEAUV.     

K. LUND-HÖIE  A. BYLTERUD 《Weed Research》1969,9(3):205-210

Summary. Tracer studies using single drops of solutions containing 3–amino-1,2,4–triazole-5–¹⁴C (aminotriazole-¹⁴C) or 2,2–dichloropropionic acid-2–¹⁴C (datapon-¹⁴C) revealed that in couch plants (Agropyron repens (L.) Beauv.) growing under field conditions in the autumn and at the stage where the aerial shoots were 40–50 cm long, both compounds moved in both symplast and apoplast. Dalapon was less mobile in the symplast than aminotriazole and only negligible amounts of dalapon were translocated to the rhizomes. The nodes of the treated shoots appeared to act as barriers to translocation, a phenomenon more pronounced for dalapon than for aminotriazole.
Application to a basal green leaf led to a more uniform distribution of the compounds within plants and rhizomes than when the application was made to the youngest fully-expanded leaf.
In couch plants with aerial shoots 10–15 cm long treated in the stubble, the distribution of both aminotriazole and dalapon was mainly restricted to the treated shoots. Even 15 days after application only trace amounts of radioactivity could be found in the rhizomes and untreated shoots.  相似文献   

EFFECT OF PYRAZON ON PHOTOSYNTHESIS OF VARIOUS PLANT SPECIES     

Y. ESHEL 《Weed Research》1969,9(3):167-172

Summary. Studies were conducted to determine the influence of pyrazon (5-amino-4-chloio-2-phenyl-3(2H)-pyridazinone) on photosynthesis. A strong inhibiting effect on O₂ evolution from leaf discs of several species was recorded. For most species a concentration of 5 × 10⁻⁵ M caused a reduction of about 50% in the rate of photosynthesis. Photosynthesis of sugar beet, highly resbtant to pyrazon, was reduced to 50% by a concentration of 7–5 × 10⁻⁵ M. Since these differences cannot account for the great divergence in susceptibility to pyrazon, it is suggested that the selectivity of this herbicide results from degradation and differential accumulation in the foliage.
Pyrazon was phytotoxic to plants of tomato and pigweed (Amaranthus retrofiexus L.) kept in the light but not when kept in the dark, after foliage application. The conclusion that pyrazon inhibits the mechanism of photosynthesis and causes starvation for carbohydrates, was strengthened by the fact that external feeding of glucose overcame the toxicity of the compound in tomato plants. These results and a possible mode of selectivity are discussed.  相似文献   

THE ADSORPTION OF LINURON, ATRAZINE AND EPTC BY MODEL ALIPHATIC ADSORBENTS AND SOIL ORGANIC PREPARATIONS     

R. J. HANCE 《Weed Research》1969,9(2):108-113

Summary. Model adsorbents were prepared by treating cellulose phosphate powder with a series of alkyltrimethylammonium compounds in which the size of the alkyl group was varied from C₈to C₁₈. The adsorption of linuron, atrazine and EPTC by these materials was found to increase logarithmically with increasing chain length. The extent of the adsorption was large compared with the adsorption of these herbicides by a humic acid and by a preparation made by removing the bulk of the inorganic constituents of a peat soil with a mixture of HCl and HF. Since soil organic matter is thought to contain alkyl groups, it is concluded that the possible influence of such groups should be considered in any discussion of the mechanisms involved in the adsorption of organic molecules by soils.
Adsorption du linuron, de I'atrazine de l'EPTC par des adsorbants de la série aliphatique et des préparations organiques de sol  相似文献   

Immunological studies in the cat. Attempts to induce delayed hypersensitivity     

I D Aitken  H B McCusker 《Research in veterinary science》1969,10(2):208-213

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Cases of Pseudorabies in Free-Living Red Foxes (Vulpes Vulpes) and in Captive Blue Foxes (Alopex Lagopus) in Denmark     

V. Bitsch  Betty Knox  Bente Munch 《Acta veterinaria Scandinavica》1969,10(2):195

In the period December 1967 through April 1969 eight spontaneous cases of pseudorabies in Danish red foxes were demonstrated by virus isolation. One fox had been kept in captivity, the remaining seven were free-living. Five of the foxes were found dead, while three, presenting abnormal behaviour when encountered, had been killed.  相似文献   

THE BASIS OF THE DIFFERENTIAL PHYTOTOXICITY OF 4-HYDROXY-3,5-DI-IODOBENZONITRlLE*     

P. J. DAVIES  D. S. H. DRENNAN  J. D. FRYER  K. HOLLY 《Weed Research》1968,8(3):233-240

Summary. Entry of ioxynil-¹⁴C into portions of leaves was greater with mustard than with barley or pea and was unrelated to stomatal density. Measurement of ioxynil content of sprayed plants showed that by increasing the concentration of ioxynil and adding a surfactant, almost as much ioxynil could be made to enter barley as entered mustard from a lower concentration without surfactant. Auto radiographs showed that a limited amount of ¹⁴C was translocated to a small extent in plants following localized application of ioxynil-¹⁴C. An experiment comparing leaf removal by cutting with destruction of equivalent leaf areas by ioxynil treatment suggested a greater translocated effect of ioxynil with mustard than with pea or barley. Les principes de la phytotoxicité différentielle du 4-hydroxy-3,5-di-iodobetZonitrile II. Absorption et migration  相似文献   

ADSORPTION AND DESORPTION OF SIMAZINE BY SOME ROTHAMSTED SOILS     

J. D. H. WILLIAMS 《Weed Research》1968,8(4):327-335

Summary. The adsorption of simazine from, and subsequent desorption into, 0–01 M calcium chloride solution was investigated using twenty-three Rothamsted soil samples from sites differing greatly in cropping history and manurial treatment. Organic carbon content was the only factor related to the ability of the soils to sorb simazine; this accounted for 90% or more of the variation between soils Equilibrium was attained during adsorption in from fewer than 2 to more than 24 hr. Equilibrium during desorption was only occasionally attained within 24 hr. Differences between theoretically predicted and measured concentrations of simazine in solution following desorption were least for soils that attained equilibrium fastest during adsorption. Differences in adsorption and desorption kinetics between soils could not be related to soil pH, organic carbon content or cropping and manuring history. Comparisons of unlimed and limed soils suggested that no simnazine was lost by acid hydrolysis during the experiments.
Adsorption et désorption de la simazine par quelques sols de Rothamsted  相似文献