Rooting success of cuttings from young Picea abies in transition to flowering competent phase

Abundant flowering occurred in a central Swedish trial with 10-yr-old Picea abies L. (Karst.) cuttings, taken on 4-yr-old seedlings. Large deviations in cone-set between clones were assumed to reflect different stages in tran sition from juvenile to flowering competent phase. Rooting success and firs t-yr growth performance (leader length, leader origin and plagiotropic grow th) were studied on cuttings originating from the upper and lower parts of the crown in 15 clones with heavy cone-set and 15 clones without cones. Twi gs from the lower part of the crown had a significantly higher rooting perc entage. Cone-set did not have an effect on any of the variables analysed. T he results suggest that flowering ability and rooting capacity are independ ent age-related processes, implying that selection for high rooting capacit y in clonal forestry does not reduce flowering competence. The results will have a great impact on breeding of P. abies, since both early flowering an d high rooting ability are important traits for reducing the turnover time of the breeding cycle.