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81.
Accessions of Australian Nicotiana species suitable as indicator hosts in the diagnosis of plant virus diseases 总被引:2,自引:0,他引:2
P. Van Dijk F. A. Van Der Meer P. G. M. Piron 《European journal of plant pathology / European Foundation for Plant Pathology》1987,93(2):73-85
When screening the genusNicotiana for sensitive and differential hosts for a group of mechanically transmissible plant viruses with narrow host ranges, development of systemic symptoms was alsmost exclusively observed in species of three closely related sections of the subgenusPetunioides. These species wereN. miersii (sectionAcuminatae),N. bigelovii andN. clevelandii (Bigelovianae) andN. benthamiana, N. cavicola, N. ingulba, N. occidentalis, N. rosulata andN. rotundifolia (Suaveolentes). Except forN. benthamiana andN. clevelandii, which are already known for their large virus ranges, they are new experimental hosts that appeared very useful for detection of viruses and for differentiation of viruses that closely resemble each other in host range. Accessions of the same species often varied largely in local and systemic viral response. EspeciallyN. benthamiana-9,N. miersii-33 andN. occidentalis-37B (code numbers given by Tobacco Research Laboratory, Oxford, N.C., USA) are recommended for routine inoculation tests. The sensitiveSuaveolentes species mentioned are native to the arid parts of Australia. Collections of these species deserve attention in studies on virus diseases of unknown etiology where experimental hosts are lacking.Samenvatting In het genusNicotiana werden vatbare, gevoelige en differentiële toetsplanten opgespoord door toetsing van vooral de collectie van het Tobacco Research Laboratory (Oxford, N.C., VS) met een aantal virussen waarvoor weinig of geen bruikbare toetsplanten bekend waren. Systemische reacties werden bijna uitsluitend in soorten van drie nauw verwante secties van het subgenusPetunioides waargenomen. Deze soorten warenN. miersii (sectieAcuminatae),N. bigelovii enN. clevelandii (Bigelovianae) enN. benthamiana, N. cavicola, N. ingulba, N. occidentalis, N. rosulata enN. rotundifolia (Suaveolentes). Behalve voor virusvermeerdering bleken deze soorten ook zeer geschikt te zijn voor differentiatie van virussen of virusstammen met een bijna gelijke waardplantenreeks.Collectienummers van één en dezelfde soort konden sterk in lokale en systemische reactie verschillen. VooralN. benthamiana-9,N. miersii-33 enN. occidentalis-37B kunnen voor routine-inoculaties worden aanbevolen. Met uitzondering vanN. benthamiana enN. clevelandii zijn de genoemde soorten of genotypen nieuwe experimentele waardplanten voor de virologie. De soorten die van de sectieSuaveolentes worden genoemd, zijn inheems in de woestijnachtige gebieden van Australië. Verzamelingen daarvan verdienen nadere aandacht bij de diagnostiek van virusziekten waarvoor nog geen experimentele waarplanten voorhanden zijn. 相似文献
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84.
Genetic diversity of Pueraria lobata (kudzu) and closely related taxa as revealed by inter-simple sequence repeat analysis 总被引:4,自引:0,他引:4
Kudzu (Pueraria lobata) is a noxious weed infesting some areas of the USA. Knowledge of its genetic variation in both native and invasive areas can lead to effective biological control measures. Inter-simple sequence repeat (ISSR) variations were studied in P. lobata and its four closely related congeneric species (P. edulis, P. montana, P. phaseoloides and P. thomsoni). ISSR results allowed a clear separation of these five species. For P. lobata, 108 plants from China and USA were analysed. The samples from the US were genetically closer to Chinese P. lobata populations than to other congeneric populations. High genetic differentiation was found for P. lobata, P. montana and P. thomsoni in Chinese samples. High genetic diversity and low population differentiation was found in P. lobata samples of the US. This supports the hypothesis of multiple introductions into the USA from different sources in Japan or China, followed by subsequent gene exchange and recombination. 相似文献
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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
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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
89.
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
90.
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