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Paleomnlagnietic polarity changes have been detected in nine deep-sea sedimentary cores (from the Pacific-Antarctic Basin) in which an extinction horizon of a radiolarian assemblage was previously independently determined. The depths of the polarity change 0.7 million years ago and the faunal boundary are closely correlated, confirming that the faunal extinction was locally virtually synchronous. Although the reason for the faunal extinction is unknown. the possibility of causal relationships between faunal extinction and factors directly involved with sedimentation rate, sedimentation rate variation, and sediment type appears to be excluded. 相似文献
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Summary Pulverized, undecayed wood was shown to be, in general, inhibitory to attempts to use enzyme-linked immunosorbent assay (ELISA)
in detecting and quantifying the decay fungus Postia placenta (Fr.) M. Lars. et Lomb. Nevertheless, the assay was still able to adequately detect the presence of P. placenta at a greater than 1: 10,000 dilution even in the presence of 0.1 g/ml spruce wood. The use of polyvinyl pyrrolidone did not
improve ELISA performance but adsorbent polystyrene had some effect on the assay sensitivity. 相似文献
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Grace E. Goodell 《国际虫害防治杂志》2013,59(3):252-253
Abstract Metsulfuron methyl (Ally‐Dupont), a sulphonylurea herbicide, was tested at rates of 0.5–2.0 g a.i./ha for the control of Striga hermonthica (Del.) Benth. in two cultivars of sorghum in pot experiments. There was good to excellent Striga control at 1.0–2.0 g a.i./ha applied either pre‐emergence or post‐emergence to CSH‐1 or N‐13 sorghum. The herbicide was unacceptably toxic to the Striga‐susceptible CSH‐1 cultivar when applied pre‐emergence, thus eroding any benefits of Striga control. In the Striga‐tolerant N‐13 cultivar there were considerable increases in the growth of infected plants. The herbicide was better tolerated from post‐emergence applications by both cultivars, and CSH‐1 plants recovered enough growth from Striga infection to produce grain yields at 1–5 and 2.0 g a.i./ha. Herbicide application at 4 weeks after planting sorghum was less damaging than at 2 weeks. Herbicide safening with 1,8‐naphthalic anhydride did not provide any additional benefits with post‐emergence application. The efficacy of the pre‐emergence herbicide was similar with surface or incorporated application. 相似文献
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Christa K. Goodell Jianqiang Zhang Erin Strait Karen Harmon Devi Patnayak Tracy Otterson Marie Culhane Jane Christopher-Hennings Travis Clement Pamela Leslie-Steen Richard Hesse Joe Anderson Kevin Skarbek Amy Vincent Pravina Kitikoon Sabrina Swenson Melinda Jenkins-Moore Jodi McGill Rolf Rauh William Nelson Catherine O’Connell Rohan Shah Chong Wang Rodger Main Jeffrey J. Zimmerman 《Canadian journal of veterinary research》2016,80(1):12-20
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Peter B Goodell 《Pest management science》2009,65(12):1293-1297
In defining the integrated control concept, Stern, Smith, van den Bosch and Hagan described ‘understanding the ecosystem’ as a key underpinning of the concept. In following years, Stern and van den Bosch continued to refine and expand the role of the ecological landscape. They and their colleagues developed cultural practices that took advantage of this understanding to limit the need of pesticide intervention in cotton in the San Joaquin Valley during the 1960s and 1970s. Research and extension activities in the intervening years built upon those fundamental concepts using geospatial tools and analytical techniques to refine current understanding and develop ecological landscape level approaches to manage Lygus hesperus (Knight) in San Joaquin Valley cotton, Gossypium hirsutum (L.) and more recently G. barbadense (L.). The result has been a significant drop in insecticide use against L. hesperus, with less than one application per season during the 1990s and early 2000s. Copyright © 2009 Society of Chemical Industry 相似文献