Rooting Ability and Properties of Different Varieties of Picea pungens Cutting

The cuttings from 3-year-old mother plant of Picea pungens were chosen to investigate their rooting ability and the optimized combination of rooting agent.Besides,the effect of different cutting conditions on the rooting of different varieties of P.pungens was studied systematically.The results showed that the callus formation of P.pungens cutting started at10 days after cutting,and after 30 days they began to root,and the peak period of rooting was 4070 days after cutting,and 80 days after cutting the rooting rate would reach to 97%.There were significant differences among the five P.pungens varieties on rooting rate and average root length,but the difference on the numbers of rooting was statistically significant.The dominant factor influencing the rooting rate was treating time.The effect of lateral branch types on rooting was extremely different.The rooting rate of first order lateral branches reached 100%,and the second lateral branches reached 88.97%.No significant difference was found between the cutting length and rooting rate and average root length,but very significant difference was found between the numbers of rooting and root effect index;the effect of cutting age on rooting had no significant differences.The optimized treatment of hormone concentration for rooting is to immerse the cuttings in 100 mg/L IBA for 0.5 hours with one-year-old 8-10 cm length first order side branches.