摘要:

AbstractThe objectives of this study were to determine the reproductive potential and the time required for completion of the life cycle ofBursaphelenchus xylophilusunder Finnish summer temperature conditions. The reproductive success ofB. xylophiluswas compared with the potential of a Finnish isolate ofB. mucronatus. The latter appeared more successful in reproduction particularly when cultured onFinns syhestriswood.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1993.tb00807.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThe inheritance of resistance toMelampsora. spp. onSalix viminalis, the variation in resistance over space and time, and rust infection rate in relation to the geographic origin of the host was studied. The analysis showed that there was considerable additive genetic variation for rust resistance, that the results did not have high repeatability over space and time, and that the material from southernmost Sweden was most sensitive to the rusts occurring in south Sweden.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1993.tb00808.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThe pathogenicity, physiology and biochemical features of three isolates ofPhytophthora. nicotianaevar.nicotianaefromEucalyptus delegatensisandE. globulusseedlings were investigated. The acid phosphatase zymograms and total protein profiles confirmed the specific identity of the 3 isolates. Despite significant differences in mycelial growth and zoosporangium production, no differences were noted in pathogenicity. Artificial inoculations revealed a variability in resistance toP. nicotianaewithinEucalyptusspecies.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1993.tb00809.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractTwo new diseases have been observed attacking willows in New Zealand. In the first instance black stem cankers formed onS. matsudana × S. alba × S. albacultivars, eventually killing them. In the second instance foliage ofS. gooddingiiandS. amygdaloideswas attacked and premature defoliation occurred. Morphological studies and host inoculations established thatGlomerella miyabeana(Colletotrichum gloeosporioidesanamorph) was the causal agent of both diseases. Foliage of cultivars exhibiting stem cankering was not attacked nor were stems of cultivars with foliar lesions. Electron microscope studies showed that conidia ofColletotrichum gloeosporioidesformed phialidically within acervuli and comdial dimensions varied significantly with hos

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1993.tb00810.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractAccording to the literature the following evidence suggests racial variation in white pine blister rust: changes over site in general level of resistance; interaction of needle spot color types with crosses of western white pine; neutralization of specific resistance reactions; bark reactions and normal cankers on the same tree.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1993.tb00811.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThe histopathology of greenPinus taedaneedles infected withMycosphaerella dearnessiiwas investigated. Cellular abnormalities observed were predominately the collapse of mesophyll cells within the limits of the symptom lesions. The epidermis, hypodermis, endodermis, transfusion tissue, and the vascular system within the lesions were not affected. Resin ducts exhibited cell necrosis and dissolution within and distal from the visible limits of lesions. An intercellular interface was present in non‐collapsed mesophyll cells at lesion limits, and the lateral extension of the interface usually corresponded to the effects observed in resin ducts distal from the lesions. Non‐stromatic hyphae were rare in and distal from lesion tissue, indicating the host tissues were affected in advance of the pathogen. The production of a toxin byM. dearnessiiis suspec

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1993.tb00812.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractDeclining Turkey oaks (Quercus cerris) in Central Italy were studied. Bacteria were isolated from woody tissues between necrotic areas and healthy tissues beneath the bark, from apparently healthy tissues and from exudates oozing from the trunk in spring. A total of 98 bacterial isolates were collected. The determination of the bacteria was by fatty acid profiling and biochemical tests.Erwinia herbicolawas frequently found both in necrotic and healthy tissues. Ice‐nucleation active species were present. None of the species isolated was considered responsible for the decli

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1993.tb00813.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY