Pathogenicity of Fusarium oxysporum f. sp. Cepae and its interaction with Pyrenochaeta terrestris on onion   总被引：1，自引：0，他引：1  

August E. Kehr  Muriel J. O'Brien  Elmo W. Davis 《Euphytica》1962,11(2):197-208

Onion breeding lines known to be resistant to Pyrenochaeta terrestris showed, in several locations, root-pruning symptoms that have been usually associated with only the action of P. terrestris. Fusarium oxysporum f. sp. cepae was invariably isolated from affected roots and the stem-plate area of these pink-root-resistant lines. Symptoms not commonly associated with the action of Fusarium, including darkening of dry scales of yellow bulbs and a reddening of scales of white bulbs, were noted. Controlled tests were conducted to establish (a) the pathogenicity of four isolates of F. oxysporum f. sp. cepae, (b) the reaction of onion breeding lines to inoculation at various temperatures with both the pink root and the Fusarium bulb rot organism, and (c) the pathogenic interaction of F. oxysporum f. sp. cepae with P. terrestris. The Fusarium isolates were pathogenic over a wide range of temperatures (20 to 38°C.). Host reaction to the organisms in combination depended on the level of susceptibility that was the greater to one or the other organism. Resistance to one did not markedly modify susceptibility to the other when both were present. Resistance to F. oxysporum f. sp. cepae was found in several onion lines.Horticulturist, Pathologist, and Horticulturist, respectively, United States Department of Agriculture, Beltsville, Maryland, U.S.A.  相似文献   

Behaviour and Socialization of the Wild Timber-Wolf     

M. W. Fox 《The Journal of small animal practice》1964,5(3):249-253

Abstract— A review article dealing with the social behaviour patterns of the wild timber-wolf, an ancestor of the domesticated dog. Investigation of these patterns may help to understand more clearly the behaviour of the dog and the influence of selection and domestication. Such behaviour patterns as flight distance, approach and avoidance behaviour, fear biting and the extinction of fear responses are discussed.
Résumé— –Article rendant compte des types de comportement social du loup des bois, ancêtre du chien domestique. Il se peut que l'étude de ces types aide à comprendre plus clairement le comportement du chien et l'influence de la sélection et de la domestication. On y discute certains types de comportement tels que la fuite, l'approche, l'esquive, l'acte de mordre sous l'effet de la peur, et la disparition des réponses à la peur.
Zusammenfassung— Ein kritischer Artikel, der sich mit den sozialen Verhaltensformen des wilden Canis occidentalis, eines Vorfahrens des Haushundes, befasst. Eine Untersuchung derselben kann dazu beitragen, das Verhalten des Hundes und den Einfluss von Zuchtwahl und Domestikation besser zu verstehen. Es werden Verhaltensformen wie Fluchtweite, Annäherungs- und Ausweichens-verhalten, Beissen aus Furcht und das Erlöschen von Furchtreaktionen diskutiert.  相似文献   

A Case of Nephrolithiasis in the Dog     

R. T. Pepper 《The Journal of small animal practice》1964,5(2):179-181

Abstract— A case of nephrolithiasis in a young boxer bitch is described and the surgical approach outlined.
Résumé— L'auteur décrit un cas de lithiase rénale chez une jeune chienne de race boxer et présente les grandes lignes de la thérapeutique chirurgicale.
Zusammenfassung— Es wird der Fall eines Nierensteinleidens bei einer jungen Boxerhündin beschrieben und ein Abriss des chirurgischen Eingriffs gegeben.  相似文献   

Second European Weed Research Council Symposium on New Herbicides, Paris, 30th November to 1st December 1965     

K. HOLLY 《Weed Research》1966,6(2):179-182

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THE USE OF HERBICIDES IN ALTERNATE HUSBANDRY AS A SUBSTITUTE FOR PLOUGHING     

R. A. ARNOTT  C. R. CLEMENT 《Weed Research》1966,6(2):142-157

Summary. It is practicable to use herbicides as an alternative to ploughing grass swards for the preparation of a seedbed for the sowing of cereals and kale. The yields of spring barley and kale following a glaass/clover sward killed with 10 lb/ac amitrole-T were similar to those obtained following ploughing. Yields of tip to 40 cwt/ac of winter wheat were obtained following grass swards killed with amitrole-T compared with up to 45 cwt/ac after ploughing.
The ideal herbicide must kill all plants in a sward and have no residual toxicity to the subsequent crop. At 10 lb/ac, amitrole-T killed most plants in the sword, but it was considered necessary to delay sowing for at least 3 weeks after spraying to minimize the danger of residual toxicity. Ploughing gave the lowest incidence of grasses persisting from the sward. Paraquat did not control clover and Agropyron repens , while broad-leaved weeds were more common on the ploughed than on the sprayed land.
There were differences in the amount of nitrogen mineralized in ploughed and In undisturbed soil, but these were insufficient to affect crop yields materially. When a lower yield followed herbicidal destruction of the sward, this was not accompanied by a reduced percentage nitrogen content.
L'emploi des déherbants pour la rénovation des prairies  相似文献   

Third Report of the Editor of Weed Research Covering the Period 1st January 1964 to 31st December 1965     

J. D. Fryer 《Weed Research》1966,6(2):186-187

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CHEMICAL AND BIOLOGICAL PROPERTIES OF TWO NEW HERBICIDES—IOXYNIL AND BROMOXYNIL     

K. CARPENTER  HELEN J. COTTRELL  W. H. DE  SILVA  B. J. HEYWOOD  W. G. LEEDS  K. F. RIVETT  MARGERY L. SOUNDY 《Weed Research》1964,4(3):175-195

Summary. The preparation of ioxynil, bromoxynil, and their salts is described, and information on solubilities and stability to storage is summarized. Although the toxicology of the herbicides is to be reported in greater detail, a preliminary statement is made here. Evidence of herbicidat activity under glasshouse conditions is indicated briefly, and supports the conclusion that both compounds are effective when applied to the foliage of a wide range of dicotyledon weed species. Seedlings of some weed species resistant to the phenoxy alkanoic acids are controlled under glasshouse conditions at doses as low as 0.125 lb/ac, and ioxynil has a wider range of activity than bromoxynil at these low doses. Graminaceous species tolerate 4–8 lb/ac of both herbicides without injury, and certain leguminous crops tolerate one or other herbicide at doses of 0.5–0.75 lb/ac. The contact action of the herbicides is rapid, there are also slower systemic effects, and seed germination is inhibited. In susceptible species the level of post-emergence activity is shown to be influenced by the growth stage of the weed, the distribution of herbicide on the foliage, and environmental factors of which light intensity appears to be most important.
Propriétés chimiques et biologiques de deux nouveaux herbicides: ioxynil et bromoxynil  相似文献   

TRIALS OF SEED DRESSINGS FOR THE CONTROL OF WHEAT BULB FLY IN SCOTLAND     

P. Osborne    W. D. Gill  E. Dunn 《Plant pathology》1964,13(1):19-19

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Retention of Selenium in Kidneys,Liver and Striated Muscle After Prolonged Feeding of Therapeutic Amounts of Sodium Selenite to Pigs     

P. Lindberg  N. Lannek 《Acta veterinaria Scandinavica》1965,6(1):217

Sodium selenite was mixed in a commercial pig food so as to increase the original selenium content (0.126 ppm) by 1.2 ppm. The supplemented food was given to 7 pigs during 78 days. A control group of as many pigs was given the non-supplemented commercial food. The pigs were killed, starting 4 hours after the last selenium-supplemented food had been given and then with intervals during the next 14 days. Small but significant increases of tissue selenium were noticed in liver and striated muscle as compared with the control animals. The kidneys showed no increase.  相似文献   

Quantitative Determination of Proteolytic,Lipolytic and Haemolytic Activities in Semen of Some Animal Species     

K. Fossum  O. Lyngset  J. Aamdal 《Acta veterinaria Scandinavica》1965,6(1):318

1. Methods for quantitative determination of proteolytic, lipolytic and haemolytic activities and egg yolk factors in semen are described.2. Comparative quantitative determinations of these enzyme activities in the semen of goat, ram, bull, boar, dog and horse have been carried out.3. Special interest attaches to the egg yolk turbidity factor which is found in goat semen and, in small concentrations, also in boar semen.4. As each species appears to have its specific enzyme pattern, regular enzymatic control does not seem to have great significance.  相似文献