Study on Softwood Cutting Propagation of Viburnum japonicum

Experiments were conducted during 2015 and 2017 on cultivation of Viburnum japonicum seedlings by cuttings from different lignified branches of 2 ~ 3 year. Cuttings were soaked 0.5 and 1 hour by different concentrations (0, 100, 200 and 300 mg·L-1) of ABT No.1, NAA and 863, and planted on sub-top soil and mixed substrate (ratio of sub-top soil, perlite and peat of 3:1:1). Determinations were implemented on adventitious root characteristics, root system and survival rate of cuttings. The result demonstrated that lignified cuttings treated by three regulators planted in June had more than 60 percent of survival rate and had rooting 30 days later, while half lignified cuttings had only 30% of survival rate and had rooting 20 days late. Rooting effect of cuttings treated by ABT-1 was better than that by NAA and 863 rooting agent. The survival rate of softwood cuttings treated by regulators increased significantly (P<0.05), and the highest survival rate of cuttings were soaked 1 hour in 200 mg·L-1 of three regulators. The survival rate of half lignified cutting treated by 1 hour in the solution of concentration of 100 mg·L-1 and 200 mg·L-1 was significantly higher than that of soaking 0.5 h, but the survival rate decreased at 300 mg·L-1. The average number of rooting was the highest in the two different substrates soaked in 200 mg·L-1 for 1.0 h, which exceeded 60 panicles and was significantly higher than that of other treatments (P<0.05). The average root length and root effect index were the best when the mixture was soaked in 300 mg·L-1 for half an hour, and the average value was 11.22 cm and 11.75, respectively. The mixed medium was more suitable for rooting, and the survival rate of the mixed medium was higher than that of pure yellow core soil at the overall level from 1.0 percent to 12.0 percent. On the whole, the best efficiency combination of cuttage breeding was to soak half an hour in 200 mg·L-1 of ABT-1 with the mixed substrates.