Chemical composition,toxic and development- and reproduction-inhibiting effects of some essential oils against Tetranychus urticae Koch (Acarina: Tetranychidae) as fumigants

Journal of Plant Diseases and Protection - The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most serious pests of many crops both indoors and outdoors in...     

Mass trapping using a new-designed light trap as a viable alternative to insecticides for the management of dipteran pests of cultivated mushrooms

Journal of Plant Diseases and Protection - In Turkey, mushroom flies (Diptera: Phoridae, Sciaridae, Scatopsidae, Cecidomyiidae) are the most serious insect pest problems, affecting the cultivation...     

Bactericides against Pasteurella multocida in whole blood, plasma and lung lavage fluid of untreated and immunized young swine and calves

The investigation of bactericidal effects in the whole blood and plasma of young pigs and calves against Pasteurella multocida has shown that such effects only come into being or are activated during the direct interaction between the host and pasteurellae, with effects being increased in previously immunized animals. The same is true for the antibodies which are detectable by indirect haemagglutination. There is no bactericidal effect in the concentrated lung lavage fluid against pasteurellae.     

Production of N2 and N2O from nitrate ingested by sheep

Supplementing ruminants with nitrate reduces their enteric methane (CH₄) emissions; however, the greenhouse gas (GHG) mitigation achieved can be partially offset by small emissions of nitrous oxide (N₂O), a more potent GHG. Sheep were dosed intraruminally with ¹⁵ to investigate whether dietary is a precursor of N₂O and/or di‐nitrogen gas (N₂), and to quantify the amounts of recovered as N₂O and N₂ in gas emissions from sheep adapted or not adapted to dietary . Ruminally cannulated sheep were adapted to a hay diet supplemented with (n = 3; 10 g /kg DM) or urea (n = 3; 5.3 g urea/kg DM). On the day of the experiment all sheep were dosed intraruminally with ¹⁵ and quickly moved into gas‐tight chambers to enable recovery of ¹⁵N in N₂O and N₂ to be measured. Measurements of gases accumulating in the chambers were made over 10 successive 50 min periods; this enabled the amount of N₂O produced, and the recovery of ¹⁵‐N in N₂O and N₂ to be determined over a total of 10 hr. Only 0.04% of labelled ‐N was recovered as N₂O, and this was not dependent (p > .05) on whether or not the animals had been adapted to dietary . Approximatively 3% of ¹⁵‐N was recovered as ¹⁵N₂, which was also not dependent (p > .05) on whether sheep had been adapted to . Because the kinetics of rumen ammonia (NH₃) were uncertain, the recovery of ¹⁵N from in rumen NH₃ could not accurately be quantified, but our results suggest that approximately 76% of dietary was converted to NH₃ in the rumen. We conclude that the small amount of recovered in N₂ was evidence of denitrification, previously thought not to occur in the rumen.     

Beobachtungen zur Ökologie und Bekämpfung des Eichenwicklers (Tortrix viridana L.) in Westfalen

Ohne Zusammenfassung Mit 9 Abbildungen     

Investigation of outer membrane proteins of Pasteurella. 2: Iron-regulated outer membrane proteins of Pasteurella multocida and Pasteurella haemolytica

Pasteurella multocida and Pasteurella haemolytica produce specific proteins in the outer membrane under iron-depleted conditions. Pasteurella multocida serovar A expresses these proteins of molecular masses of 76 and 96 kDa as determined by electrophoresis. The analogous serovar D produces a further iron-regulated protein of 85 kDa. The Pasteurella haemolytica strains of serovar A1, A6 and T contain iron-regulated outer membrane proteins of molecular masses of 71, 77 and 100 kDa. These proteins possess binding positions for iron ions. Both Pasteurella multocida and Pasteurella haemolytica strains utilize iron from porcine and bovine transferrin, but not from haemin and haemoglobin.     

Evaluation of some selective insecticides and their combinations with summer oil for the control of the pear psyllaCacopsylla pyri

A field trial was carried out to evaluate the efficacy of several selective insecticides for the control of pear psyllaCacopsylla pyri (L.) (Hemiptera: Psyllidae) in two successive years. Three insect growth regulators (IGRs) — diflubenzuron, pyriproxyfen and teflubenzuron, and an amin-hydrazine derivative — amitraz, were evaluated singly and in combination with summer oil (1%). All insecticides were applied at recommended label rates in both years. When compared with the untreated control, all insecticides alone and their combinations with summer oil, except for pyriproxyfen alone, provided control of young (1st and 2nd instars) nymphs. However, combined applications of these insecticides and summer oil were more effective than either insecticide alone for controlling the egg and young nymph stages of the pest. The products were less effective against older (3rd–5th instars) nymphs, even in combination with summer oil, and failed to suppress the population of older nymphs. Adding oil to sprays also delayed oviposition by winterform and summerform females. With the exception of oil with amitraz, combinations of insecticides with summer oil did not cause any phytotoxicity during the study.