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911.
912.
As a result of the study carried out between 2007 and 2009 in the eastern part of the Black Sea Region of Turkey, 4 genera and 17 species were determined as new records for the Turkish aphid fauna. New recorded species are Aphis arbuti, Aphis cytisorum, Aphis kachkoulii, Cavariella digitata, Chaitophorus kapuri, Chaitophorus longisetosus, Cinara pinivora, Illinoia lambersi, Myzus beybienkoi, Neobetulaphis pusilla, Phyllaphis fagifoliae, Pseudessigella brachychaeta, Schizaphis rotundiventris, Symdobious oblongus, Thecabius lysimachiae, Thelaxes californica and Tinocallis takachihoensis. With these new records, the number of genera increased to 134 and the number of the species in the Turkish aphid fauna amounted to about 480. Since Turkey has a huge range of agricultural crops and a great diversity in its natural flora, research conducted on the Turkish aphid fauna has current and future indications for plant protection.  相似文献   
913.
The compatibility and protectant potential of Calneem® oil derived from the neem tree Azadirachta indica and two parasitoids, Habrobracon hebetor and Venturia canescens, for the control of the rice moth Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) and the tropical warehouse moth Cadra cautella Walker (Lepidoptera: Pyralidae) in stored rice and wheat, were evaluated in the laboratory. Calneem® oil (= neem oil) is a biopesticide produced, registered and marketed in Ghana by AQUA AGRIC Community Projects (AACP/Caldor Ghana Ltd., Tema). It contains 0.3% azadirachtin as its major active ingredient. The oil was emulsified with water using 0.07% soap. Fourth instar moth larvae were held in grain treated with neem oil only, grain treated with one of the parasitoids only, grain treated with a combination of neem and one of the parasitoids, and a control with untreated grain. Neem oil was applied at concentrations from 5,000 to 30,000 ppm. All samples were kept in growth cabinets maintained at 25°C and 65–70% r.h. Adult emergence was recorded after 4 weeks. Parasitoid or neem treatments alone reduced the emergence of C. cephalonica and C. cautella. In general, parasitoid releases were as effective as a combination of neem oil and parasitoids. At the lowest dose, 5,000 ppm, the combination of neem and parasitoid was more effective than the neem alone. The number of adults of H. hebetor and V. canescens that emerged in rice containing either parasitoids alone or in combination with neem oil was similar. This indicates minimal or no adverse effect of neem oil on the two parasitoids. It is thus possible to incorporate neem oil in a well-designed pest management program with parasitoids.  相似文献   
914.

Mitteilungen

Mitteilungen aus der Industrie  相似文献   
915.
There is no available data published related to the dissemination of bacterial canker caused by Clavibacter michiganensis subsp. michiganensis (Cmm) and its genetic diversity in Turkey. It is important to control new introduced inoculum sources by commercial seeds and seedlings. Pathogens were identified by morphological features and the identity was confirmed by PCR amplification using a specific primer PSA-4, PSA-R in addition to microbiological tests. ISSR markers showing high polymorphism ratios were selected and used to characterize Cmm strains. The collected strains were classified into different groups on the basis of ISSR-PCR fingerprints, which showed remarkable genetic specificity and diversity not previously identified in Cmm, suggesting that genetic differences are related to dissemination of the pathogen in the region. This is the first ever study carried out on the characterization of Cmm using ISSR. The selected ISSR primers to characterize Cmm can be used to determine genetic differences in further studies.  相似文献   
916.
BACKGROUND: Isothiocyanates (ITCs) released by the enzymatic hydrolysis of glucosinolates in the Brassicaceae are potentially useful for controlling fungal pathogens. In vitro activity of pure ITCs against Sclerotinia sclerotiorum (Lib.) de Bary was studied by adding them to glass filters in petri dishes and dissolving them in the growing media. RESULTS: Methyl, allyl and benzyl ITCs were the most fungitoxic of the compounds in bioassays with S. sclerotiorum isolate Ss31. In the volatile phase, mycelial growth was completely inhibited by these three compounds. Aromatic ITCs were less toxic in the petri dishes but were more toxic than aliphatic ITCs when dissolved in the agar. Benzyl ITC exhibited the highest inhibitory effect on sclerotial germination, with an EC50 value of 75.1 µmol L?1. Butyl and benzyl ITCs reduced apothecial production of S. sclerotiorum by 92.5% at the highest concentration. In in vivo assay, only allyl and 2‐phenylethyl ITCs reduced disease incidence (by 76.7 and 70% respectively) at low concentrations. CONCLUSION: Sclerotinia sclerotiorum in the soil might be suppressed by the higher concentrations of allyl and benzyl ITCs released from decomposition of Brassica juncea, B. carinata, B. nigra and Sinapis spp. Copyright © 2011 Society of Chemical Industry  相似文献   
917.
Journal of Plant Diseases and Protection - Stem injection of prohexadione carboxylic acid (pca) was tested to prevent blossom infection by the fire blight pathogen Erwinia amylovora on apple trees,...  相似文献   
918.
919.
Deuterium-labeled citronellyl diphosphate and citronellyl beta-D-glucoside were fed to Pelargonium graveolens. Both precursors were converted into cis-/trans-rose oxide. Citronellyl diphosphate is more effectively converted into rose oxide. The phloem exudate of P. graveolens was analyzed after enzymatic cleavage of the glucosidated and phosphorylated volatiles. It could be shown that glucosidically bound citronellol is translocated in the plant. Phosphorylated citronellol could not be detected.  相似文献   
920.
In the lower part of a raised bog profile from Langegger Filz, southern Bavaria, the Pb and Cd concentrations were comparatively low while considerably higher concentrations of both elements were observed in the upper section of the profile. The peat layers with the highest concentrations of Pb and Cd were found to date from the Iron Age, the Roman Age, and the Middle Ages. The Fagus pollen curve reflects the beginning of a beech decline exactly in those peat layers in which the start of the Pb increase is visible. Therefore it appears that metal smelting caused a local release of heavy metals which were subsequently deposited in the raised bog. Metals could only be smelted when wood was cut and burned, and beech charcoal was preferred as it produces relatively high temperatures. The good agreement between the Pb concentration profile and the pollen analyses suggests that the bog provides an accurate record of atmospheric Pb deposition.  相似文献   
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