Contributions to the knowledge of conifer aphid fauna in Turkey and their zoogeographical distribution

The Aphidoidea (Homoptera) has 29 species which attack coniferous trees in Turkey. The family Aphididae has 25 (Aphidinae, 1; Lachninae, 22; Mindarinae, 2) species and the Adelgidae, 4. The tribe Cinarini in Lachninae has alone 22 species most of which are important. Especially Cinara cedri Mimeur on Cedrus libani and C. pilicornis (Hartig) on Picea spp. are harmful species. Schizolachnus pineti (Fabricius) is also very important. An Eastern Palearctic species in the tribe Macrosiphini in Aphidinae, Elatobium momii (Shinji), is numerous on Abies bornmülleriana in Bursa-Uluda forests. Pineus orientalis (Dreyfus) in the family of Adelgidae (Chermesidae) is the most destructive in our Picea orientalis forests in Artvin area (Eastern Black-Sea Section). 21 species out of 29 aphids on coniferous trees are of European origin; only 4 are Mediterranean, 2 Caucasus and Turkistan, one Eastern Palearctic and one of Cosmopolitan origin.     

Changes in clinical values of cattle infected with Clostridium chauvoei CH3 strain and a local Kad1 strain. Haematological values

Clostridium chauvoei CH3 and Kad1 strains were found to cause marked changes in the blood parameters during the course of blackleg disease. These changes displayed by CH3 were found to be more marked than the local Kad1 strain. Results of changes in the haematological values in calves infected with blackleg organisms, showed an increase in RBC, PCV, Hb and the total leukocyte count. MCHC and MCH remained within normal range values, however, a terminal significant increase of MCV was obtained. Thrombocytes showed a steady drop after infection to the time of death of the animals.     

Electroencephalographic observation on sheep and cattle with experimental cerebrocortical necrosis

Nine Suffolk sheep and 4 Holstein cattle were employed to observe electroencephalographic changes in experimental cerebrocortical necrosis. Amprolium (600 mg/kg/day) alone was given intraruminally 6 sheep and 4 cattle, all of which showed neurological signs and abnormal electroencephalograms. Both amprolium and thiamine (200 mg/day) and thiamine (50 mg/day) alone were given 2 and 1 sheep, respectively, as controls, which did not show any abnormal signs. Abnormal electroencephalograms included continuous slow waves and long-lasting spindles, both of which appeared diffusely and were seen subclinically or with neurological signs. The spindles consisted of slow waves or sharp- (or spike-) and-slow-wave complexes with or without convulsive seizures even during the convulsion stage. Conversely, the seizures occurred with the spindles or slow waves.     

Freezing of stallion semen with addition of glycine betaine

The effect of addition of glycine betaine to a lactose-EDTA freezing medium on the post-thaw motility of stallion semen was determined. The first three semen-rich fractions of nine stallions were collected with an open-end Krakow artificial vagina on consecutive weekdays. Semen was frozen using the Hannover method with freezing media containing glycine betaine in various concentrations from 0 to 5%. After thawing, sperm motility was analysed both by a light microscope and by a Hamilton-Thorn Motility Analyser. Total and progressive post-thaw motilities of semen containing 0.25-3% glycine betaine did not differ significantly from the total and progressive post-thaw motilities of semen frozen without glycine betaine. The total and progressive post-thaw motilities of semen containing 4 or 5% glycine betaine were significantly lower (P < 0.001) than those of semen without glycine betaine. In conclusion, glycine betaine did not show any beneficial effect on the post-thaw motility of stallion semen when semen was frozen using the Hannover method.     

Detection of feline coronavirus infection in captive cheetahs (Acinonyx jubatus) by polymerase chain reaction.

Feline coronavirus genetic elements were detected by polymerase chain reaction from blood, fecal samples, and effusive fluid collected from 33 cheetahs in the U.S.A. Feline coronavirus-specific serum antibodies were also measured by indirect immunofluorescence. Ten cheetahs were positive for viral shedding by polymerase chain reaction, whereas 13 were seropositive by immunofluorescence. Results of serology did not consistently correlate with shedding of virus, and the capture antigen used for detection of feline coronavirus-specific antibodies had a significant impact on results. Testing of samples from one population over a 1-yr period indicated chronic infection in some animals. These relatively healthy carrier animals were a source of virus for contact animals. Screening programs in cheetah populations for feline coronavirus infection may be most reliable if a combination of serologic analysis and viral detection by polymerase chain reaction is used.     

The EFSA quantitative approach to pest risk assessment – methodological aspects and case studies

A new method for pest risk assessment and the identification and evaluation of risk‐reducing options is currently under development by the European Food Safety Authority (EFSA) Plant Health Panel. The draft method has been tested on pests of concern to the European Union (EU). The method is adaptable and can focus either on all the steps and sub‐steps of the assessment process or on specific parts if necessary. It is based on assessing changes in pest population abundance as the major driver of the impact on cultivated plants and on the environment. Like other pest risk assessment systems the method asks questions about the likelihood and magnitude of factors that contribute to risk. Responses can be based on data or expert judgment. Crucially, the approach is quantitative, and it captures uncertainty through the provision by risk assessors of quantile estimates of the probability distributions for the assessed variables and parameters. The assessment is based on comparisons between different scenarios, and the method integrates risk‐reducing options where they apply to a scenario, for example current regulation against a scenario where risk‐reducing options are not applied. A strategy has been developed to communicate the results of the risk assessment in a clear, comparable and transparent way, with the aim of providing the requestor of the risk assessment with a useful answer to the question(s) posed to the EFSA Plant Health Panel. The method has been applied to four case studies, two fungi, Ceratocystis platani and Cryphonectria parasitica, the nematode Ditylenchus destructor and the Grapevine flavescence dorée phytoplasma. Selected results from these case studies illustrate the types of output that the method can deliver.     

Cobalt reduces nitrate inhibition of nodulation in mungbean (Vigna radiata)

 A cobalt-mediated decrease in ethylene production reduced the inhibition of nodulation by nitrate in Vigna radiata (mungbean). Nitrate increased the ethylene production in 5-day-old seedlings, while it caused a reduction in the nodulation status (nodule number and nodule weight) and nodule efficiency (acetylene reduction activity) in mungbean plants. The application of cobalt chloride inhibited nitrate-affected ethylene production and also decreased the inhibitory effect of nitrate on nodulation. The effect of cobalt was most marked on nodule number. Received: 6 August 1999