Epsilon Archive for Student Projects

Abstract

A necessary decision when a clonal seed orchard is established is the choice of the clones. The goal of a seed orchard is to produce many seeds of a high genetic quality. Almost all earlier studies have focused on selecting genotypes with good genetic constitution, and little attention has been focused on the options to affect cone yield by clone selection. This study investigates if the cone production of clones can be predicted by the cone set of the selected plus tree or the performance of its ramets in a clone bank.
Two main sources of data for predicting female fertility under seed orchard conditions are used – cone set in a clone bank at Sävar comprising most early plus tree selections in northern Sweden, 748 clones with 4 ramets per clone; and verbal evaluation of cone set from 69 plus tree. These data were compared with female fertility of the same clones growing as grafts on seven locations (seed orchards or clonal tests) No significant relationship was found. This strongly indicates that it is almost impossible to make meaningful predictions of future cone production in seed orchards from cone set information from plus trees or young clone banks. In order to utilize fully the collected data some more calculations and comparisons were made. They show that the clones planted in the clone bank at Sävar behave different due to their origin. The clones with more northern origin grow slower than the other ones and even with the same diameter they produce fewer cones. No relation was found between the origin of the clones and their survival ability.