Preliminary Study On Introduction,Cultivation And Grafting Of Pinus Densiflora Var.Zhangwuensis In Beijing Area

Pinus densiflora var.zhangwuensis is a new species of tree found in Zhanggutai District of Liaoning Province in 1990.It has a very high value of application and promotion.Currently,it has been introduced and promoted in large scale in Liaoning Province,Heilongjiang Province,Gansu Province,Shanxi Province,Shaanxi Province,Inner Mongolia Autonomous Region and other places,and no larce-scale introduction promotion has been officially conducted in the Beijing region.Due to the limited number of seeds of Pinus densiflora var.zhangwuensis and the unstable genetic traits of seedlings,the only grafting technique that can be applied in production practices is not comprehensive enough,and effective cultivation and breeding techniques are urgently needed.Pinus sylvestris var.mongolica is a variant of Pinus sylvestris.Its excellent biological characteristics such as drought resistance,cold-resistance,adaptability,and fast-growing are recognized by many forestry workers.This study uses it as a comparative tree species,and in order to fully demonstrate the excellent biological characteristics of Pinus densiflora var.zhangwuensis.In this experiment,through the research of planting Pinus densiflora var.zhangwuensis in Beijing Area in 2012 and 2016,we have initially explored suitable grafting breeding and cultivation management measures in Beijing Area,in order to provide certain reference and technical support for the introduction and extension of Pinus densiflora var.zhangwuensis in Beijing Area in the futureThe main results are as follows:(1)Pinus densiflora var.zhangwuensis introduced survival rate in Beijing Area can reach more than 90%,and the overall growth condition is better than Pinus sylvestris var.mongolica,and there is no obvious pests and diseases.Under the same management and protection measures,the seedling height,ground diameter,and annual growth of Pinus densiflora var.zhangwuensis of 5a and 6a were significantly higher than Pinus sylvestris var.mongolica of the same age(2)There was a significant difference in the survival rate of grafting under different grafting times and scion types.The time selection of Grafting can guarantee higher survival rate in the morning between late April and early May.The survival rate of grafting is higher when the length of the scion slice is controlled between 6cm and 7cm.The source of scion did not have a significant effect on graft survival.(3)In the cultivation process of Pinus densiflora var.zhangwuensis,single application or mixed application of ABT No.3 rooting powder and microbial inoculants can significantly increase ground diameter,seedling height,annual growth and biomass,and ABT No.3 rooting powder has the best effect..(4)In the cultivation process of Pinus densiflora var.zhangwuensis,single application of ABT No.3 rooting powder can significantly increase the content of chlorophyll content?soluble sugar and soluble protein.The use of microbial inoculants alone can significantly increase the soluble protein and chlorophyll content,also increase the soluble sugar content,but the effect is not significant.Mixed application is better than single application.