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Albrecht Hase 《Journal of pest science》1931,7(3):25-28
Ohne Zusammenfassung
Mit 1 Abbildung. 相似文献
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Eckhard Koch Annegret Schmitt Dietrich Stephan Carola Kromphardt Marga Jahn Hermann-Josef Krauthausen Gustaf Forsberg Sigrid Werner Tahsein Amein Sandra A. I. Wright Federico Tinivella Maria L. Gullino Steven J. Roberts Jan van der Wolf Steven P. C. Groot 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(1):99-112
The current study was initiated to evaluate the efficacy of physical methods (hot water, aerated steam, electron treatment) and agents of natural origin (resistance inducers, plant derived products, micro-organisms) as seed treatments of carrots for control of Alternaria dauci and A. radicina. Control of both Alternaria species by seed treatment with the resistance inducers was generally poor. Results were also not satisfactory with most of the formulated commercial micro-organism preparations. Based on the average of five field trials, one of these, BA 2552 (Pseudomonas chlororaphis), provided a low but significant increase in plant stand. Among the experimental micro-organisms, the best results were obtained with Pseudomonas sp. strain MF 416 and Clonostachys rosea strain IK726. A similar level of efficacy was provided by seed treatment with an emulsion (1%) of thyme oil in water. Good and consistent control was generally achieved with the physical methods aerated steam, hot water and electron treatment. Aerated steam treatment was, apart from the thiram-containing chemical standard, the best single treatment, and its performance may at least partially be due to extensive pre-testing, resulting in dosages optimally adapted to the respective seed lot. In some of the experiments the effect of the hot water treatment, which was tested at a fixed, not specifically adapted dosage, was significantly improved when combined with a Pseudomonas sp. MF 416 or C. rosea IK726 treatment. The results are discussed in relation to the outcome of experiments in which the same seed treatment methods and agents were tested in other seed-borne vegetable pathosystems. 相似文献
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Splenic haemangiosarcomas are frequently seen in dogs. Because of their bad prognosis differentiation from other benign splenic lesions are of prognostic importance. 相似文献
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Denis J. Sonwa Ousmane Coulibaly A. Akinwumi Adesina Stephan F. Weise Mathurin Tchatat 《Integrated Pest Management Reviews》2002,7(3):191-199
Imports of pesticides have long been subsidised for use in the cocoa agroforests of the humid forest zone of southern Cameroon.
With the liberalisation of the cocoa and pesticides sectors and the devaluation of the local currency (CFA franc), farmers
are facing fluctuations in the price paid for cocoa and the high cost of farm inputs. Without the support of the extension
services, they themselves have developed traditional integrated control methods based on the use of plant extracts mixed with
conventional pesticides. From a survey of 300 cocoa farmers, the study assesses the farmers' command of these methods, the
pests controlled, the problems encountered and the institutional constraints in the definition and dissemination of integrated
control methods. The study concludes with recommendations for research and development towards the better definition and dissemination
of integrated control methods.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Journal of Plant Diseases and Protection - The following text summarizes the different perspectives of presenters participating in the section Plant Protection in the Tropics and Subtropics, 61st... 相似文献
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While the possible negative effect of employer‐sponsored health insurance on labor mobility (job lock) has spawned substantial research, little research has considered differences in job lock between rural and urban areas. Job lock might differ in rural areas because of specific features of rural economies, in particular, the thinness of rural labor markets. This paper estimates measures of job lock for rural and urban areas. Parameter estimates suggest that it is larger in rural areas. The results also indicate that nonwage benefits such as retirement plans, paid vacation, and sick pay are more important factors in married rural workers decisions to change jobs while wages are a more important factor in the transition decisions of single urban workers. 相似文献