Detection of a broad range of potato viruses in a single assay by mechanical inoculation of herbaceous test plants   总被引：1，自引：0，他引：1  

J. T. J. Verhoeven  J. W. Roenhorst 《EPPO Bulletin》2003,33(2):305-311

To optimize mechanical inoculation of test plants as part of the regulated post-entry quarantine testing of stolon- and tuber-forming Solanum spp. (including potato), nine test plant species have been screened for their ability to detect 22 potato-infecting viruses. These included all the common mechanically transmissible potato viruses and most of the viruses found in potato incidentally. The symptoms observed after mechanical inoculation are shown for each combination of test plant species and virus. Under given conditions, Nicotiana occidentalis -P1 and Nicotiana hesperis -67A were found to detect reliably 20 and 18 out of 22 viruses respectively. These and former results on the seed-transmissible viruses and Andean potato mottle virus demonstrate that these Nicotiana species are very suitable for post-entry quarantine testing. Addition of either Chenopodium amaranticolor or Chenopodium quinoa to these two species may slightly extend the range of viruses. Therefore, using C. amaranticolor / C. quinoa , N. hesperis -67A and N. occidentalis -P1 for the biological screening of imported Solanum spp. will improve both the efficiency and the quality of post-entry quarantine testing.  相似文献   

Sectioned pelvic fin ray ageing of muskellunge Esox masquinongy from a Virginia river: comparisons among readers, with cleithrum estimates, and with tag–recapture growth data     

T. O. BRENDEN  E. M. HALLERMAN  & B. R. MURPHY 《Fisheries Management and Ecology》2006,13(1):31-37

Abstract  The potential utility of pelvic fin rays as ageing structures was evaluated for southern US muskellunge Esox masquinongy Mitchill populations by comparing age estimates among three readers and against cleithrum estimates, and by comparing observed length changes of tagged fish with changes predicted from growth equations based on pelvic fin ray age estimates. Mean coefficient of variation in age estimates among all readers and between the two readers with prior ageing experience was 17.8% and 5.6%, respectively. Exact and within 1-year agreement rates between pelvic fin rays and cleithra were 76% and 100%, respectively. Mean (± 2 SE) estimated absolute error between observed and predicted length changes for 13 tagged muskellunge was 30 ± 14 mm. This evaluation indicated that pelvic fin rays may prove to be a useful, non-lethal method for ageing muskellunge in southern US waters. Validation studies are still needed to ensure that growth rings form consistently throughout fish's life span.  相似文献   

Linear methods to estimate kinships from genetic marker data for the construction of core sets in genetic conservation schemes     

H. Eding  T. H. E. Meuwissen 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2003,120(5):289-302

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THE TRAVERTINE RECORD OF BLAKE SEA     

Macdougal DT  Sykes G 《Science (New York, N.Y.)》1915,42(1073):133-134

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Illusive memory     

T WB 《Science (New York, N.Y.)》1884,3(59):345

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THE STRUCTURE OF PANTOTHENIC ACID     

Williams RJ  Major RT 《Science (New York, N.Y.)》1940,91(2358):246-247

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水杨酸对桃树花期抗寒性的影响   总被引：6，自引：1，他引：5  

郭守华  杨晴  杨晓玲  张曼 《园艺学报》2004,31(5):675-675

在华北和东北地区桃树花期低温(0℃左右)引起坐果率严重下降的现象时有发生。以管理手段延迟花期成本较高。水杨酸(SA)能诱导抗氰呼吸，有产热效应。本试验对施用外源SA降低桃树花期低温伤害的效应进行了研究，期望为桃树花期提供低成本的抗寒手段。  相似文献   

Crystalluria. Observations, interpretations, and misinterpretations     

C A Osborne  T D O'Brien  H K Ghobrial  L Meihak  J B Stevens 《Veterinary Clinics of North America: Small Animal Practice》1986,16(1):45-65

Crystalluria results from oversaturation of urine with crystallogenic substance. However, oversaturation may occur as a result of in vitro as well as in vivo events. The microscopic appearance of crystals only represents a tentative identification of their composition because variable conditions associated with their formation, growth, and dissolution may alter their appearance. Definitive identification is dependent on physical methods such as optical crystallography, x-ray diffraction, and electron microscopic analysis.  相似文献   

植物病原荧光假单胞杆菌数值分类研究     

杨合同  任欣正 《植物病理学报》1994,24(2):139-145

 采用数值分类法研究了来自21种寄主植物96个病原荧光假单胞菌菌株(包括5株非荧光菌)的分类问题。结果表明,所有参试荧光菌菌株可分成两大组,第一组(组I)生长较慢,精氨酸双水解酶呈阴性,营养谱窄,多数菌株不利用DL-苯丙氨酸,L-苯丙氨酸,L-羟脯氨酸,L-异亮氨酸,L-色氨酸,L-瓜氨酸,DL-nor-缬氨酸,L-胱氨酸,单宁酸和鼠李糖作为唯一碳源,不能利用天冬氨酸作为唯一碳源和氮源,而第二组(组Ⅱ)的菌株可利用这些化合物。组I的菌株可分为10个亚组(I₁-I₁₀),亚组与致病变种或命名种基本对应,与寄主来源密切相关;亚组间的区别在于它们利用底物的能力不同。组Ⅱ均具有精氨酸双水解酶,营养谱广泛。  相似文献   

Association of tumor-associated antigen on the proliferation of bovine leukemia virus-infected lymphoblastoid B-cell lines.     

M P Yang  R Goitsuka  H Tsujimoto  M Onuma  A Hasegawa 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(4):757-761

The association of tumor-associated antigen (TAA) on the proliferation of BLV-infected lymphoblastoid B-cell lines (BL2M3 and BL312) was investigated. Flow cytometric analysis of the expression of TAA with monoclonal antibody (mAb) c143 showed high expression of TAA on the surfaces of BL2M3 and BL312 cells. A large amount of TAA was found in the culture supernatant of BL2M3 and BL312 cells as well as in the lysates of BL2M3 and BL312 cells. Culture supernatant but not lysates of BL2M3 and BL312 cells promoted the growth of either BL2M3 cells or BL312 cells. Furthermore, this growth promoting activity in culture supernatants of BL2M3 and BL312 cells was inhibited in a dose-dependent manner when cultured with mAb c143. These results suggested that TAA may be involved in the growth factor-mediated cell growth of bovine B-lymphoblastoid cell lines expressing TAA on their cell surface.  相似文献