摘要:

SUMMARYPurified preparations of particles of peanut clump virus (PCV) hadA260/A280values (corrected for light scattering) of 1.00. They contained rod‐shaped particles with sedimentation coefficients of 183Sand 224S, and a density in CsCl of 1.32 g/ml. PCV infected 36 species in 8 plant families. No serological relationship was detected between PCV and barley stripe mosaic, beet necrotic yellow vein,Nicotiana velutinamosaic and tobacco mosaic viruses.PCV was seed‐borne for two generations in groundnut (Arachis hypogaea) but was not seed‐borne in great millet (Sorghum arundinaceum), Phaseolus mungoorNicotiana benthamiana.Seedlings of groundnut, great millet and wheat (Triticum aestivum) became infected when grown in soil from groundnut fields with outbreaks of clump disease, and the infectivity of soil survived air‐drying at 25°C for 3 months. Groundnut seedlings became infected when grown in sterilised soil contaminated with washed roots of naturally‐infectedS. arundinaceumbut not in soil to which roots of naturally infected groundnut or shoots of infected groundnut were added, or in which mechanically inoculated groundnut seedlings were grown at the same time. The patchy distribution of PCV in a crop was related to the infectivity of the soil for groundnut and to the presence ofPolymyxa graminisresting spores which could be detected in the roots ofS. arundinaceumbait seedlings, but not in those of groundnut.The results indicate that PCV is transmitted by a vector that is resistant to air‐drying and closely associated withS. arundinaceumroots. For these reasonsP. graminisis thought to be the v

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1981.tb02998.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

SUMMARYAdult individuals of honey bee colonies in Britain are commonly infected with several small RNA viruses. Black queen cell virus and bee virus Y are the commonest and occur most frequently about June, together withNosema apiswith which both viruses are intimately but independently associated. Bee virus X is less common than bee virus Y and showed no pronounced seasonal fluctuations in local surveys, but was detected mostly in winter and early spring. Sacbrood virus occurred in adults of most local colonies in summer, chronic paralysis virus and cloudy wing particle occurred commonly but without seasonal variations and acute paralysis occurred commonly throughout the active season of bees but does not multiply sufficiently to cause overt disease. Slow paralysis virus was rare.

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1981.tb02999.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

SUMMARYA simple machined dispenser is described, capable of providing rapid repetitive delivery of standard volumes of potato cyst nematode cysts. Standard volumes of cysts of mixed sizes, drawn from unsieved populations ofG. rostochiensis, contain titres of infective eggs and larvae which are largely independent of cyst numbers; the method reduces inoculum variability compared with other cyst inoculation techniques. Standard volumes of cysts of mixed sizes may be used directly as the inoculum for plant resistance testing programmes without the operator error associated with hand‐held scoops or the need for the subjective and time consuming selection of groups of individual cyst

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1981.tb03000.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1981.tb03001.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1981.tb03002.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1981.tb03003.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY