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本文介绍了采用气相色谱法用HP-5毛细管柱,以邻苯二甲酸二异戊酯为内标物,氢火焰离子化检测器对嘧菌酯·丙环唑悬乳剂进行定量分析。结果表明,嘧菌酯、丙环唑的线性相关系数为1.0000、1.0000平均回收率为100.15%、99.95%;标准偏差为0.03、0.007;变异系数为0.42%、0.06%。 相似文献
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4月18日,全球农药登记一体化和小作物/特殊作物农药登记研讨会在陕西西安召开。会议由农业部农药检定所(ICAMA)、美国农业部(USDA)和美国环境保护署(USEPA)共同发起并组织召开。农业部农药检定所张延秋所长、顾宝根副所长,美国农业部高级项目主管Jason Sandahl先生, 相似文献
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T. Soliman M. C. M. Mourits A. G. J. M. Oude Lansink W. van der Werf 《Plant pathology》2013,62(5):1106-1113
International agreements on plant health and trade require that regulating a pest should be justified by economic impact assessment. Economic impact assessments are usually qualitative, weakening the objective and transparency of the regulation decision. This study assessed the potential economic impacts of the invasion of the plant pathogenic bacterium ‘Candidatus Liberibacter solanacearum’ into the European Union in order to economically justify a decision on its quarantine status. Direct economic impacts resulting from yield loss in potato and tomato were computed using partial budgeting at a regional scale, while total economic impacts on the potato and tomato markets were computed using partial equilibrium modelling at the EU scale. Annual direct impacts at the most likely infestation level were estimated at €222 m for the whole EU. Uncertainty analysis showed a distribution of foreseeable annual impacts with a 5th percentile of €192 m, and a 95th percentile of €512 m. Increased market prices of potato and tomato resulting from reduced supply were found to increase profits for non‐infested producers and to compensate in part for the production losses of infested producers, with consumers paying for this mitigation of impacts on producers. The expected negative impact on societal welfare at the most likely infestation level is less than the estimated direct impacts, viz. €114 m/year. The potential economic impacts of ‘Ca. L. solanacearum’ in the European Union are demonstrably of major importance. Therefore, a decision to categorize this organism as a quarantine pest is supported. 相似文献
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Transmission of ‘Candidatus Phytoplasma pyri’ by naturally infected Cacopsylla pyri to peach,an approach to the epidemiology of peach yellow leaf roll (PYLR) in Spain
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Peach orchards in the northeast of Spain were severely affected in 2012 by a previously unreported disease in this area. The symptoms included early reddening, leaf curling, decline, abnormal fruits, and in some cases death of the peach trees. All the infected peach samples were positive for ‘Candidatus Phytoplasma pyri’, but none were infected by the ‘Ca. Phytoplasma prunorum’. In this work, potential vectors able to transmit ‘Ca. Phytoplasma pyri’ from pear to peach and between peach trees were studied and their infective potential was analysed at different times of the year. Transmission trials of the phytoplasma with potential vectors to an artificial feeding medium for insects and to healthy peach trees were conducted. Additionally, isolated phytoplasmas were genetically characterized to determine which isolates were able to infect peach trees. Results showed that the only insect species captured inside peach plots that was a carrier of the ‘Ca. Phytoplasma pyri’ phytoplasma was Cacopsylla pyri. Other insect species captured and known to be phytoplasma transmitters were present in very low numbers, and were not infected with ‘Ca. Phytoplasma pyri’ phytoplasma. A total of 1928 individuals of C. pyri were captured in the peach orchards, of which around 49% were phytoplasma carriers. All the peach trees exposed to C. pyri in 2014, and 65% in 2015, were infected by ‘Ca. Phytoplasma pyri’ 1 year after exposure, showing that this species is able to transmit the phytoplasma to peach. Molecular characterization showed that some genotypes are preferentially determined in peach. 相似文献
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Large‐scale virulence tests using trees or saplings are expensive, time‐consuming and require a considerable amount of space. The suitability of using ‘Golden Delicious’ apples as a rapid screen for identifying Ophiostoma novo‐ulmi transformants with reduced virulence was thus evaluated. When a collection of O. novo‐ulmi field isolates belonging to subspecies novo‐ulmi or americana was inoculated to apples, members of subsp. novo‐ulmi induced, on average, larger necrotic lesions than subsp. americana isolates. The size of the lesions on apples was not correlated with mycelial growth rate of isolates on nutrient agar. Insertional mutants from O. novo‐ulmi subsp. novo‐ulmi isolate H327 were inoculated to ‘Golden Delicious’ apples and Ulmus parvifolia × U. americana saplings in parallel experiments. Results clearly indicated that the O. novo‐ulmi transformants included several exhibiting significantly altered levels of virulence. Variability among replicates within a treatment was reduced in apple inoculation data compared to elm sapling data. Overall, the ‘Golden Delicious’ apple assay was found to be an excellent means for rapidly assessing the virulence level of O. novo‐ulmi isolates. 相似文献