摘要:

Agropyronmosaic virus (AMV) from Ontario and wheat streak mosaic virus (WSMV) from Alberta readily infected wheat (Triticum aestivumL.) causing mosaic symptoms that could be differentiated only when carefully compared. All isolates of AMV infectedAgropyron repens(L.) Beauv. but not oats (Avena sativaL.). WSMV infected oats but notA. repens. Hordeummosaic virus (HMV) from Alberta caused mottle rather than streak symptoms on wheat, rye, and other common hosts of WSMV, and did not infectA. repens, but, like AMV, it was not transmitted byAceria tulipae(K.), the vector of WSMV. It infectedHordeum jubatumL., which is not susceptible to AMV or WSMV. It ranked between AMV and WSMV in longevity and tolerance to heat and pH. The particles were flexuous rods similar to those of WSMV, which appear less flexuous and slightly shorter than particles of AMV.The temperatures at which the viruses multiplied and caused symptoms on wheat ranged from 15° to 33 °C for WSMV and 10° to 30° for AMV. HMV multiplied at all temperatures from 10° to 33 °C but caused symptoms only at 10° to 30 °C.Specific antisera were prepared by partially purifying the viruses by differential centrifugation of juice from diseased wheat, emulsifying the juice with adjuvant, then injecting rabbits intramuscularly. The precipitation titers against their homologous viruses were 1/640, 1/1280, and 1/1280 for the WSMV, AMV, and HMV antisera respectively. The WSMV antiserum did not react with the heterologous viruses, but two HMV antisera had a precipitation titer of 1/16 against AMV, and an AMV antiserum had a titer of 1/10 againt WSMV. Cross absorption of each of the antisera with the heterologous viruses did not reduce the titers against the homologous viruses.The infection of wheat with a mild strain of any of the three viruses protected against later infection by a severe strain of the same virus. Both AMV and HMV were synergistic in combination with WSMV. Serological tests demonstrated that both AMV and HMV multiplied in wheat simultaneously inoculated with both viruses, but systemic infection with either virus protected the plants against later infection by the other.Despite general similarities in physical characteristics and effects on wheat, specific differences in other characteristics show that AMV, HMV, and WSMV are sufficiently different to be designated as different viruses rather than closely related strains of one virus.

ISSN:0008-4026    

DOI:10.1139/b66-131

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Chromosome numbers are reported for 65 species of Canadian arctic plants. The chromosome numbers ofParrya arcticaR. Br. (2n = 14 and ca. 21) and ofPuccinellia poaceaTh. Sor. (2n = 14) are reported for the first time. New numbers are recorded for some species and many species are shown to contain two or more chromosome races. A rationale supporting the counting of chromosomes from populations throughout the ranges of all plant species is given.

ISSN:0008-4026    

DOI:10.1139/b66-132

出版商:NRC Research Press    

年代:1966

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b66-133

出版商:NRC Research Press    

年代:1966

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b66-134

出版商:NRC Research Press    

年代:1966

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b66-135

出版商:NRC Research Press    

年代:1966

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b66-136

出版商:NRC Research Press    

年代:1966

数据来源: NRC