Parameter values for the main scenario A and the alternative scenarios. Scenario B values were the same as for scenario A except that the number of parents per grandparent was 3 and annual budget per grandparent was 20.
|Parameters||Main scenario||Alternative scenarios|
|Additive variance ()a||1||1|
|Dominance variance in proportion of the additive variance ()b||0.25||0; 1|
|Narrow-sense heritability (h2) (obtained by changing )c||0.125||0.05; 0.2; 0.5; 1|
|Coefficient of additive variation at mature age adjusted by the correlation between observed value||11||5; 15|
|and value for forestry, % (CVAm)c|
|Number of grandparents (Ngandparents)c||50||50|
|Number of parents mated within each family and expressed per grandparent (p)||6||To be optimised|
|Weight for group coancestry||0||100|
|Breeding population size (NBP)||300||(= 50p)|
|Time not used for testing, years (Tnot − testing)c||5 (top-grafts)||4; 10 (grafts)|
|Testing time, years (Ttesting)c||15||To be optimised|
|The fixed costs per grandparent, “plants”(Cfixed)c||100||0; 200|
|Cost of one parent, “plants”(Cparent)c||50||0; 100|
|Cost of one test plant, “plants”(Cplant)c||1||1|
|Annual budget per grandparent, “plants”(the constraint)c||50||30; 40; 70; 100|
|Annual genetic gain (or group merit), %||To be maximized|
The additive variance in the observed values used for selection. It is convenient to set the additive variance as 1 and to express the other variance components as proportions of the additive variance.
The dominance variance makes up 25% of additive variance in a forest tree breeding population and is a rather typical value used in similar studies (e.g. Danusevičius and Lindgren, 2002).