Publikasjoner

NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.

1991

Sammendrag

The Eurasian sprucc bark beetle, Ips typogaphus carries spores of several fungi induding Ophiostoma bicolor, O. pellicillatum and O. polonicum. However, after attack on Norway spruce trees O. polonicum is the pioneer invader of the sapwood while other species follow. To determine the causes behind this distinct succession experiments were performed comparing growth rate, tolerance to oxygen-deficient conditions and to spruce resin between these early invaders. In sealed tubes with limited oxygen. O. polonicum grew for a longer time than three other species regularly associated with I. typagraphus in Norway. The non-volatile components of lesion resin induced by fungal attack, as opposed to preformed resin, inhihited the growth of all species, but partirularly O. polonicum. O. polonicum grew rapidly on malt agar, but not faster than some of the other species associated with I. typographus. It is concluded that rapid growth and the abilily lo tolerate low oxygen pressure are important attributes for primary invaders, allowing tree resistance mechanisms to be overcome following mass inoculation.

Sammendrag

Support is given for the dark respiration as a limiting factor for growth at low temperatures. The existence of a so-called alternative respiration that is not linked to the growth process, supports this hypothesis, because of its possible function as a stabilizing factor (overflow function). Physiological mechanisms influencing plant survival in a cold environment and tree-line forming processes are discussed.