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101.
102.
Robert A. Haack 《Integrated Pest Management Reviews》2001,6(3-4):253-282
Since 1985, the U.S. Department of Agriculture, Animal and Plant Health Inspection Service has maintained the 'Port Information Network' (PIN) database for plant pests intercepted at the U.S. ports of entry. As of August 2001, PIN contained 6825 records of beetles (Coleoptera) in the family Scolytidae that had been intercepted during the years 1985–2000 from countries outside of North America. Of the 6825 scolytid interceptions, 2740 (40%) were identified to the species level, 2336 (34%) to only the genus level, and 1749 (26%) were identified to only the family level. Of the 49 identified scolytid genera, the 10 most common were Hypothenemus (821 interceptions), Pityogenes (662), Ips (544), Coccotrypes (520), Orthotomicus (461), Hylurgops (327), Hylurgus (266), Tomicus (194), Dryocoetes (166), and Hylastes (142). The 10 most common identified species were Pityogenes chalcographus (565 interceptions), Orthotomicus erosus (385), Hylurgops palliatus (295), Ips typographus (286), Hylurgus ligniperda (217), Ips sexdentatus (157), Tomicus piniperda (155), Hylastes ater (75), Hypothenemus hampei (62), and Polygraphus poligraphus (48). Of these 10 species, H. palliatus, H. ligniperda, and T. piniperda are known to be established in the continental U.S. The scolytids were intercepted from 117 different countries; the top 12 countries were Italy (1090 interceptions), Germany (756), Spain (457), Mexico (425), Jamaica (398), Belgium (352), France (261), China (255), Russia (247), India (224), U.K. (151), and Portugal (150). The scolytids were intercepted in 35 U.S. states and 97 port cities. In general, there was a positive relationship between the number of scolytid interceptions from individual countries and the value of the imports from those countries. Overall, 73% of the scolytids were found in solid wood packing materials, 22% in food or plants, and 5% in other or unspecified materials. The products most commonly associated with scolytid-infested wood packing materials were tiles, marble, machinery, steel, parts, ironware, granite, aluminum, slate, and iron. The food products and plants that were commonly infested with scolytids included nutmeg, palms, coffee beans, kola nuts, and macadamia nuts. 相似文献
103.
104.
David E. Barnekow Stephen M. Brown Sandra L. Byrne Arlene W. Hamburg Mike A. Huskin Andrea M. Leisure 《Pest management science》1995,43(3):211-219
The metabolism of cis- and trans-1,3-dichloropropene (1,3-D) was studied in soybean plants grown in soil treated 24 days prior to planting with [U-14C]E- and Z-1,3-dichloropropene at 380 liters ha?1. Isolation and identification of the 14C residue from soybean plants at 84 days (forage) and 176 days (mature) after application showed that no 1,3-dichloropropene or its putative metabolites, 3-chloroallyl alcohol and 3-chloroacrylic acid, could be detected in any of the tissues. The components of the 14C residue included major plant constituents (i.e. fatty acids, protein, pigments, organic acids, sucrose and other carbohydrates, and lignin). 相似文献
105.
武威地区天然草地有毒植物及其防除 总被引:12,自引:2,他引:10
对武威地区天然草地有毒植物的种类,分布及其对草地的危害情况进行了调查研究,结果表明,全区天然草地共有毒植物172号,分属31科84属,平均2.15种/m^2,盖度达4.41%地上部分生物量11.28g/m^2。对草地危害的主要黄花棘豆,甘肃棘豆,小花棘豆,狼毒和马草,受侵害的草地主要是山地草甸和山地草原,通过分析,提出了有毒植物防除和利用的建议。 相似文献
106.
番茄及其近缘野生种茎段原生质体培养的研究 总被引:3,自引:0,他引:3
利用番茄茎段作为原生质体来源的外植仁,在适宜的培养基中,成功地获得了野生秘鲁番茄(Lycopersicon peruvianum Mill.)、栽培番茄‘粤农2号’(Lycopersicon esculentum ‘Yuenong No.2’)和番茄近缘里生种类番茄茄(Solanum lycoersicoides Dun.)的再生植株。3种材料的再生植侏移植到土壤中均能正常生长,植株性状与对照无差 相似文献
107.
Cogongrass ( Imperata cylindrica (L.) Beauv.), an invasive C4 perennial grass, negatively influences native plant communities by forming dense monotypic stands that alter ecosystem properties and lower local species diversity. A hypothesized mechanism by which cogongrass achieves competitive dominance is a novel use of below-ground vegetative disturbance of neighboring vegetation (i.e. puncturing). However, very little empirical evidence is found in the peer-reviewed literature to quantify this phenomenon, much less establish it as a true form of competitive interaction. The present field study was conducted to quantify the occurrence of rhizome-mediated, below-ground vegetative penetration, both interspecifically and intraspecifically, document how this phenomenon is influenced by spatial location relative to the cogongrass stand, and determine the role that above-ground and below-ground biomass might have in the process. Analyses of 100 sod samples indicated that rhizome-mediated, below-ground vegetative penetration is a much larger intraspecific phenomenon than an interspecific one. The data also strongly suggested spatial location as a significant factor, with most penetrations occurring in the interior of a cogongrass stand as opposed to the advancing border. Significant correlations between rhizome-mediated, below-ground vegetative penetration and above-ground cogongrass biomass were found in the overall plot analysis and most strongly in the advancing border of the cogongrass stands. 相似文献
108.
The recent upsurgence ofBemisia tabaci (Genn.) as an important insect pest and vector ofTomato yellow leaf curl virus (TYLCV) is directly linked to serious damage to tomato crops grown throughout Japan. The molecular genetic identification
and phylogenetic relationships of 12B. tabaci populations collected from representative locations in Japan were determined based on the mitochondrial cytochrome oxidase
I (mtCOI) sequence. Phylogenetic analysis of the whitefly mtCOI sequence indicated that both the invasive B and Q biotypes
now occur in Japan. The Q biotype was found at four locations: Mihara in Hiroshima, Nishigoshi in Kumamoto, Miyanojo and Okuchi
in Kagoshima prefectures; the remaining eight collections were identified as the B biotype. This is the first report of the
introduction of Q biotype in Japan.
http://www.phytoparasitica.org posting July 21, 2006. 相似文献
109.
Two trials were conducted in 2002 with 14-day-old spring canola (Brassica napus L.) seedlings to evaluate the effects of previous leaf injuries of different cultivars on subsequent injury by western black
flea beetle (WBFB),Phyllotreta pusilla Horn (Coleoptera: Chrysomelidae), under greenhouse conditions in Colorado (USA). Previous leaf cutting was found to have
only minor effects on subsequent infestation and injury by WBFB, and such effects may be cultivar-specific. Only IMC205 showed
significant differences by more than one parameter during these studies; cultivars Excel and 46A65 showed no responses in
injury or infestation between previously cut and uncut plants.
http://www.phytoparasitica.org posting Nov. 14, 2005. 相似文献
110.
随着转基因植物的大规模商业化种植,其对蜂类等有益昆虫的影响成为研究转基因生物风险评估的主要内容。一方面蜜蜂等蜂类取食植物花粉,有可能直接接触到杀虫蛋白,产生毒性效应;另一方面转基因植物的性状、营养成分等可能发生变化,对蜜蜂的行为可能产生潜在影响。本文综述了目前转基因植物对蜂类昆虫安全性研究进展,并提出克服转基因植物对非靶标生物可能的负面效应的治理对策,以期对转基因植物生物安全性的研究提供科学依据。 相似文献