THE INFLUENCE OF IRRIGATION, FERTILIZING AND MCPA ON THE COMPETITION BETWEEN SPRING CEREALS AND WEEDS     

H. SUOMELA  J. PAATELA 《Weed Research》1962,2(2):90-99

Summary. The average air-dry yield of weeds on fallow plots was about four times as large (2660 kg/ha) as the yield of weeds which developed among spring cereal crops (740 kg/ha). Application of fertilizers increased the number of weeds and their average weight on both irrigated and non-irrigated plots. Treatment with MCPA reduced the weed yield to 36% on fallow plots and to 26% on weedy cereal plots. It was more effective on fertilized plots than on unfertilized plots, but irrigation made little difference to its effectiveness. The space left by the destroyed weeds was mainly occupied by Agropyron repens . Oats were better able to compete with weeds than were wheat and barley. On unfertilized and non-irrigated plots spraying with MCPA (1-26 kg/ha) at the beginning of shooting significantly reduced the yields of weed-free barley. The yields of sprayed oats and wheat were also below the yields from the unsprayed although the reductions were not significant at the 5% level. However, on a number of fertilized and irrigated plots, both weedy and hand-weeded , on which the plants had better growing conditions, MCPA resulted in a significant increase in the grain yield of barley and oats.
Influence de l'irrigation, de la fertilisation et du MCPA sur la compétition entre céréales de printemps et mauvaises herbes  相似文献   

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   

Glucuronic acid metabolism in dairy cows. Excretion in the urine     

J Ushijima  K Koyama  A Yuasa 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1964,26(1):43-51

  相似文献   

Inheritance of tolerance to halo blight in bean     

P N Patel  J C Walker 《Phytopathology》1966,56(6):681-682

  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

  相似文献   

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   

An attempt to reduce calcium phosphate deposits on cobaltic oxide pellets by citric acid treatment     

E D Andrews  B J Stephenson  C E Isaacs 《New Zealand veterinary journal》1964,12(5):113-117

  相似文献   

Mycotoxicoses. 3. Antifungal and antimycotoxic activity of 8-hydroxyquinoline under laboratory and simulated field conditions     

J Forgacs  H Koch  R H White-Stevens 《Avian diseases》1963,7(1):56-66

  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   

Adsorption of Chlorpropham by Different Soils     

H. A. ROBERTS  B. J. WILSON 《Weed Research》1965,5(4):348-350

  相似文献