Tree breeding for
resistance conference in
By: Þröstur Eysteinsson
The Nordic Group for the Managemant
of Genetic Resources of Trees held its annual conference in
The invited speaker, Dr. Alvin Yanchuk
from the BC Ministry of Forests, Victoria, British Columbia, Canada, covered
the topic well in a keynote paper titled “Tree Breeding for Resistance to
Biotic and Abiotic Stresses:new
targets for old programs?“ Among the things he pointed out was the need to
conserve genetic diversity, taking the example of Pinus
lambertiana, where only 2% of trees have genetic
resistance to white pine blister rust (Cronartium ribicola). That small proportion of the population is
essential to successful breeding for blister rust resistance. If forest
management does not insure conservation of genetic diversity, the resistance
trait could be lost from some populations.
A total of 17 papers and 5 posters were presented. Six of
them dealt with various aspects of resistance to root- and stem rot fungi, the
general message being that considerable genetic variation exists within tree
species that can be utilised in breeding for
resistance. Six papers/posters dealt with various forms of abiotic
damage, usually related to climatic adaptation. Here again, a great deal of
variation exists within populations with which to work in breeding and
selection. Expression of genes involved in adaptive traits can also be modified
by the environment during seed formation. A smaller number of papers/posters
dealt with other fungal diseases, herbivory
resistance and technical aspects of breeding for resistance.
On an excursion to Jutland, the participants visited
several experiments and seed orchards of a variety of tree species, including
Sitka and Norway spruce, Douglas-fir and the Danish specialty; Christmas trees.