Premium
Defence reactions of Norway spruce ( Picea abies Karst.) to controlled attacks of Ips typographus (L.) (Col., Scolytidae) in relation to tree parameters
Author(s) -
Baier P.
Publication year - 1996
Publication title -
journal of applied entomology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.795
H-Index - 60
eISSN - 1439-0418
pISSN - 0931-2048
DOI - 10.1111/j.1439-0418.1996.tb01656.x
Subject(s) - picea abies , phloem , biology , karst , bark (sound) , botany , bark beetle , positive correlation , ecology , medicine , paleontology
The defence reactions of 105 Norway spruce trees in response to controlled attacks of Ips typographus were analysed and five groups with different defence reactions were recognized. Growth‐ and vigour‐indices showed no significant correlation with the induced reactions, but parameters of bark anatomy were most important. Due to secondary radial growth, the formation of periderm was intensified. Thereby, the density and thickness of radial resin ducts in the phloem increased, the number of boring attempts decreased and the number of boring attempts, defended by primary resin exudation, increased. Seasonal changes in the defence reaction could partly be traced back to changes in starch reserves in the phloem. Temporary changes in carbohydrate and water balance may affect the defences, but structural and anatomical properties of the bark govern the basic conditions for the responses to invading bark beetles.