Ten geleide     

J. Dekker  H. de Fluiter 《European journal of plant pathology / European Foundation for Plant Pathology》1969,75(1-2):7-7

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On the existence in France of pancreatic necrosis in the rainbow trout (Salmo gairdneri). (Preliminary note)     

P Besse  P de Kinkelin 《Bulletin de l'Académie vétérinaire de France》1965,38(5):185-190

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Closing of the International Symposium Plant Diseases and Pests in a Developing Europe     

H. J. de Fluiter 《European journal of plant pathology / European Foundation for Plant Pathology》1967,73(1):169-170

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Continuous Conduction of Action Potentials by Peripheral Myelinated Nerve Fibers     

de No RL  Honrubia V 《Science (New York, N.Y.)》1963,140(3565):383

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De Levenswijze en de Bestrijding van de Rondknopmijt van Zwarte Bes,Cecidophyopsis ribis     

M. van de Vrie 《European journal of plant pathology / European Foundation for Plant Pathology》1967,73(5-6):170-180

The biology, ecology and control of the black currant gall mite,Cecidophyopsis ribis, formerly calledPhytoptus ribis, Eriophyes ribis orCecidophyes ribis, was studied in the field. These observations rendered the following results. The number of mites in the infested buds varied greatly according to the season; low numbers were present during May, June and July, high numbers during November until April. The number of generations is unknown. The migration period is closely related to the development of the host plant; mites migrate during the blossom period in spring. Newly formed axillary buds are infested while a larger proportion of the mites congregate in the tips of the shoots; these mites infest the axillary buds after the end of the migration period. Dissemination of the mites can take place by wind transportation, leaping, insect transportation, and transportation by man. Buds on the basal parts and on the terminal parts of newly formed shoots appeared to be more heavily infested than buds on the middle parts of the shoots. This preference can be explained by the behaviour of the mites; the basal buds are infested during the migration period, the terminal buds are infested by the mites from the growing tips. Damage consists of deformation of the buds which do not give flowers, and the transmission of reversion virus which causes sterility of the host plant. Control can be achieved by frequent applications of endosulfan. In nurseries endrin can be applied to prevent infestation.Samenvatting De levenswijze van de rondknopmijtCecidophyopsis ribis werd onder veldomstandigheden bestudeerd. Daarbij bleek dat gedurende de periode van oktober tot april grote aantallen mijten in de aangetaste knoppen aanwezig kunnen zijn. Infectie van de nieuwe knoppen vindt plaats vanaf half april tot half mei; er is een duidelijk verband tussen het ontwikkeljngsstadium van de waardplant en het tot stand komen van de infectie. De mijten vertonen een voorkeur voor de knoppen aan de basis en aan de einden der scheuten. Verplaatsing vindt plaats door het lopen langs de takken; de mijten kunnen ook meegedragen worden door insekten of verplaatst worden door de wind. Schade ontstaat doordat de aangetaste knoppen niet uitlopen en de rondknopmijten het brandnetelbladvirus overbrengen. Als ziektebeeld ontstaat dan het zgn. brandnetelblad; door dit virus wordt onvruchtbaarheid van de struiken veroorzaakt. Bestrijding van de mijten is mogelijk door toepassing van endosulfan en endrin gedurende de migratieperiode. Op vruchtdragende struiken kan endrin niet toegepast worden in verband met het tijdens de oogst aanwezige residu van dit rniddel.Gedetacheerd bij het Proefstation voor de Fruitteelt in volle grond, Wilhelminadorp.  相似文献   

Parathion-resistentie van het fruitspint     

M. van de Vrie 《European journal of plant pathology / European Foundation for Plant Pathology》1954,60(1):78-78

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Der Ernteverlust als Summe einzelner Faktoren     

H. Güde 《Forstwissenschaftliches Centralblatt》1957,76(1-2):1-14

Ohne Zusammenfassung  相似文献   

Vagus indigestion related to a liver hemangioma.          下载免费PDF全文

R A Curtis  J J de Groot 《The Canadian veterinary journal. La revue veterinaire canadienne》1967,8(3):75-76

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Dictyocaulus viviparus in calves: effect of rotational grazing on the development of infections.     

M Eysker  J H Boersema  J B Cornelissen  F N Kooyman  W A de Leeuw 《Veterinary parasitology》1992,41(1-2):127-135

A study was made of the possibility of reducing lungworm infections in young grazing calves by rotational grazing for weekly periods on six paddocks. For this purpose three groups of four calves each were grazed on separate pastures in 1989, whereas a fourth group served as a permanently housed control group. Two groups of calves were infected experimentally with six doses of 10 larvae of Dictyocaulus viviparus during the first 3 weeks on pasture. In the third group, low natural infections with overwintered larvae occurred. One of the experimentally infected groups was rotationally grazed for weekly periods on six small plots while both other groups were set-stocked. Faecal larval counts and worm counts in tracer calves demonstrated lower lungworm infections in the rotationally grazed group than in both set-stocked groups. However, the numbers of worms found after challenge infection and subsequent necropsy were relatively high in the rotationally grazed group, indicating that development of immunity was less than in both other groups. Owing to the dry weather conditions in the summer of 1989, no serious clinical signs of husk developed in any of the three groups. These dry conditions, however, did not prevent the build-up of heavy pasture infectivity with gastrointestinal nematodes resulting in heavy worm burdens and serious clinical signs in tracer calves grazing for 4 days in August and September-October, respectively. This implies that rotational grazing did not have a clear effect on build-up of gastrointestinal nematode infections.  相似文献   

Mechanism of resistance to fenarimol in Aspergillus nidulans     

M.A. de Waard  J.G.M. van Nistelrooy 《Pesticide biochemistry and physiology》1979,10(2):219-229

Mycelial uptake of [¹⁴C]fenarimol (10 μg/ml) by 20 fenarimol-resistant mutants of Aspergillus nidulans was compared with uptake by wild-type strain 003. Uptake of the fungicide during the initial 10 min of incubation was significantly lower in all mutant strains than in the wild-type strain indicating that resistance is related with reduced uptake. Upon prolonged incubation a gradual decrease of accumulated radioactivity in the wild-type strain was observed. A few mutants displayed resistance to unrelated chemicals such as p-fluorophenylalanine or d-serine; this phenomenon appeared not to be due to a decreased uptake of the corresponding natural amino acids. Incorporation of [³H]adenine and [¹⁴C]leucine by mycelium of mutant M193 was hardly inhibited after 5 hr of incubation with the fungicide, whereas a distinct effect was found with the wild-type strain. At this time also fungitoxicity to the wild-type strain became apparent. Probably, this effect is indirectly caused by inhibition of ergosterol biosynthesis. Mycelium of mutant M193 incorporated [¹⁴C]acetate slightly less effectively than the wild-type strain. After 2 hr of incubation with this radiochemical leakage of [¹⁴C]acetate metabolites from mycelium of the mutant strain was observed. This indicates that resistance might be correlated with increased excretion of fungal metabolites, which in turn may be related with reduced fitness of fenarimol-resistant mutants.  相似文献