Resistance to the green spruce aphid (Elatobium abietinum Walker) in progenies of Sitka spruce (Picea sitchensis (Bong) Carr.)

Damage caused by Elatobium abietinum was estimated as needle loss in a progeny trial of Sitka spruce in Denmark in 1990 and 1992. The parents of the progeny had been selected for putative aphid resistance during a massive attack of aphids in 1957. Needle loss was significantly less in the progeny than in a standard provenance, Family heritability was estimated as 0.72 (P > 0.0001). Aphid damage had an impact on growth and vigour of trees following warm winters in 1989 and since, but no correlation could be found between growth parameters and damage of different families. Due to high heritability and large variation, high gains are expected by breeding. Practical and theoretical consequences of including aphid resistance in breeding programmes of Sitka spruce are discussed. (C) 1997 Elsevier Science B.V.