摘要:

AbstractThe sequence of events leading to the restoration of an intact periderm surface in the stem bark ofPinus sylvestrisfollowing wounding and challenge withArmillaria ostoyaewas determined. A sub‐erized impervious tissue (SIT) was produced outside the necrophylactic periderm (NP). Al‐thoughA. ostoyaeinitially infected wounded bark with intracelfularly growing hyphae, these died before penetrating deeply into the bark. Later, intercellularly growing rhizomorphs, which had also developed from the inoculum, penetrated the NP and infected the functional phloem/ cambial zone. Compared to the reactions in uninfected wounded bark, theA. ostoyaeinfection delayed the formation of NP and reduced the frequency of cells involved in lignification and in SIT, but increased the number of lignified cell layers. The rhizomorph infection reached deeper and lignification was more pronounced in defoliated seedlings than in non‐defoliated ones. The importance of structural responses in defence againstA. ostoyaeis disc

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1992.tb01434.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractField studies of damage and mortality were carried out through 16 years in six young plantations, mostly ofPinus contorta, but alsoP. sylvestrisandP. sibirica.Differences between pine species,P. contortaprovenances, sites, and soil treatments are reported and discussed, as are influences of environment, climatic conditions, snow cover, and nutrient deficiency.Gremmeniella abietinawas by far the most important cause of mortality; there were great differences between the sites as to development and seriousness. Other important causes of mortality and damage werePhacidium infestans, elk(Alces alcesL.), voles, and snow pressure.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1992.tb01435.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractConcentrations of the stilbene glucosides astringin and isorhapontin, which ranged from 5 to 50 mg/g fresh weight inPicea abiesbark, decreased in response toin vivoinfection with the root‐rot fungusHeterobasidion annosum.The initial concentration of the stilbene astringin was negatively correlated with the depth of hyphal penetration. Resin acid contents increased following infec‐tion, but were not correlated with the depth of hyphal penetration. The spatial distribution of stilbene glucosides in spruce stem, root collar and root bark, and the seasonal variations in con‐centration, were esti

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1992.tb01436.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractSevere damage was caused to coastal forest vegetation by the Libeccio, a sea wind blowing against the Italian coast from W‐SW. The behaviour of common cypress(Cupressus sempervirens), smooth cypress (C.glabra)and Monterey cypress (C.macrocarpa)in response to the Libeccio windstorms of 1990 was compared with that due to treatments with the surfactant ABS (sodium dodecylbenzenesulphonate). As regards both the nature and the intensity of the damage to the leaf waxes, the surge damage caused by the windstorms differed little from that produced artifi‐cially by ABS spr

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1992.tb01437.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractNorway spruce(Picea abies)seedlings, 2–4 years old, were subjected to different degrees of stress. Drought stress affected the predisposition to infection byHeterobasidion annosumin the same way in root wood, stem wood and stem bark. At high water potentials (−3 to −5 bar) resistance was high, at intermediate levels (‐ 5 to ‐ 15 bar) it was low but increased again at water potentials below ‐ 8 to ‐ 15 bar. Neither light nor oxygen deficiencies appeared to have adverse effects on resistance. Total length of unsuberized roots was a sensitive indication of strain on

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1992.tb01438.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY