Development of Cutting Propagation Techniques of Deutzia amurensia

Deutzia amurensia is an important ornamental shrub with important medicinal and economic value. In this study, a five-factor (types of cuttings, types and concentrations of rooting hormones, treatment duration, and types of rooting media) and four-level orthogonal experiment was conducted using softwood cuttings and hardwood cuttings of Deutzia amurensia. The results indicated that the two-year-old hardwood cuttings treated with NAA at 500 mg·L^-1 solution for 90 seconds and rooted in  perlite  produced the better rooting percentage of 60.5% and had better survival rate at 89.5%. The treatments were significant and the highest survival rate was 47.4% higher than that of the control. The four-year-old hardwood cuttings produced the lowest survival rate at 82.1%. The rooting percentage decreased with increasing age of hardwood cuttings, i.e. two-year-old cuttings had the highest rooting percentage (60.5%), followed by three-year-old cuttings (39.6%), and four-year-old cuttings (13.8%). The rooting percentage and survival rate of softwood cuttings on Deutzia amurensia were higher than those of hardwood cuttings. The softwood cuttings treated with GGR of 1000 mg·L^-1 solution for 90 seconds and rooted in  vermiculite  produced the highest rooting percentage and the highest survival rate. The highest rooting percentage, 98.3%, was 1.36 times higher than that of the control. The highest survival rate, 95.8%, was 42.4% higher than that of the control. In addition, the survival rate and the rooting percentage of the softwood cuttings did not decrease with hormone treatment duration and concentrations reached 90 seconds and 1000 mg·L^-1. Deutzia amurensia should be regenerated using softwood cuttings during busy growing season. Altermatively, two-year-old hardwood cuttings with hormone treatment could be rooted for commercial production.