Study On Regeneration Technique Of Acer Truncatum Elite Trees

In recent years, the usage of Acer truncatum seed forbio-energy development and edible oil is in national plans. As barren hills and landscaping tree species, the Acer truncatum reproduces mostly by seedling propagation. Because of the existence of the juvenile period, the Acer truncatum enters the stage of fruiting late. The space of fruits is small. The natural variability is high, while superior strain rate is low, which results in low yield of Acer truncatum fruit. Research on asexual propagation technique is important to the development and utilization of Acer truncatum.Thus, experiment of one year old rootstock rapid breeding and superior tree grafting were conducted.1)After one months’ collection and preservation, germination rate of Acer truncatum seeds could reach to 100% with testa and endotesta removed. While germination rate were 89% with endotesta remained and 70% with testa removed.The germination rate and speed were higher (92%) under hormone treatment compared with cold stratification treatment and water soaking treatment. After gauze treatment of seeds with testa removed, the seed germination rate was slightly increased from 81.7% to 87.9%, which indicated that the substances contained in endotesta inhibited the germination of seeds.2)The study showed that root stock growth of greenhouse seedling was higher than that of direct seeding of field in the same period. And grafting standard can be achieved earlier, germination rate and grafting rate were improved significantly under greenhouse seedling. Average seedling height and diameter of greenhouse seeding in January 20th were significantly higher than those of greenhouse seeding as well as field direct seeding in April, and was improved 24.43%、24.76%a、18.57% and 18.70% respectively.3)In May 14th and June 19th, the seedlings were sprayed on the leaves. The compound fertilizer had significant influence on the growth of seedlings. Compared with the control, the seedling height and ground diameter were increased by 23.24% and 24.56%, respectively.4)The grafting experiment showed that the thicker the one-year rootstock diameter, the higher the grafting survival rate was. While the diameter was above 7mm, grafting survival rate was 75%.The grafting survival rate was 55.1% and 58.82% under T-shaped budding and block bud grafting respectively. After twice grafting, There was no significant difference between current rootstock grafting survival rate(60%) and one-year stump plant grafting survival rate(62.3%). Thus current rootstock grafting could greatly shorten the life of grafted seedlings through grafts taking.5)Through plant tissue culture, primary results showed that the best sampling period was April. The optimum conditions for the disinfection and sterilization of explants were 1% or 2% NaClO solution of 10min. The suitable hormone germination of axillary bud was DKW+6-B A0.15mg/L+IBA0.01 mg/L+TDZ0.02mg/L.