摘要:

SUMMARYHop plants became infected with the hop strain of arabis mosaic virus (AMV(H)) when grown in hopfield and woodland soil in which infected plants had been growing. Infection occurred in soil infested with the dagger nematodeXiphinema diversicaudatum, but neither in uninfested soil nor in soil previously heated to kill nematodes.X. diversicaudatumtransferred direct from hop soils transmitted AMV(H) to young herbaceous plants and to hop seedlings; some of the hop seedlings developed nettlehead disease. A larger proportion of plants was infected usingX. diversicaudatumobtained from a woodland soil and then given access to the roots of hop or herbaceous plants infected with AMV(H). AMV(H) was transmitted by adults and by larvae, in which the virus persisted for at least 36 and 29 wk, respectively.Difficulties were encountered in detecting AMV(H) in infected hop plants, due partly to the delay in virus movement from roots to shoots. Infection of hop shoots was seldom detected until the year after the roots were infested and sometimes nettlehead symptoms did not appear until the third year. Isolates of arabis mosiac virus from strawberry did not infect hop. The results are discussed in relation to the etiology and control of nettlehead and related diseases of hop.

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1974.tb01361.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

SUMMARYField and insectary tests confirmed that the black‐currant gall mite (Cecidophyopsis ribis) is unable to survive on gooseberry and red currant.A dominant geneCe, controlling resistance to the gall mite, has been transferred from gooseberry to black currant. Resistant, large‐fruited, self‐fertile black currants of commercial potential have been obtained in the third backcross.One accession ofRibes bracteosumand three ofR. americanumproved field susceptible to the gall mite, but twenty‐four accessions of otherRibesspecies remained free from galled buds for at least 3 years in an infecti

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1974.tb01362.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

SUMMARYStrong resistance to American gooseberry mildew (Sphaerotheca mors‐uvae) occurred in eight out of tenF1progenies from crosses of resistant North American Eugrossularia species with European gooseberry cultivars or seedlings. Bimodal segregations in four of theseF1's and in oneF1derived from the wild EuropeanRibes grossularia uva‐crispasuggested that each donor carried a major dominant resistance gene. Such a gene,Sph1was identified in a first backcross fromR. oxyacanthoides.Accessions ofR. oxyacanthoides, R. leptanthumandR. watsonianumproved the most promising donors of resistance to mildew and leaf spot (Pseudopeziza rib

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1974.tb01363.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

The Council of the Association of Applied Biologists is concerned about the standards of presentation and illustration of some papers at meetings of the Association. The following notes have therefore been drawn up to emphasize those points which are considered to require special attention and to assist speakers to present their talks effectively.These notes may be copied in whole or in part without further permission.

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1974.tb01364.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1974.tb01365.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY