Growth Index Analysis of Mature Fruits of Pinus koraiensis in the Hunshandake Sandy Land
Pinus sylvestris var.mongolica is an excellent species for sand control and afforestation in the Khorchin and Hunshandake sandy lands.However,the economic benefits of young artificial forests of Pi-nus sylvestris var.mongolica are relatively low.Grafting Pinus koraiensis onto Pinus sylvestris var.mongolica rootstocks provides a new approach to managing these forests.In 2019,Pinus koraiensis was grafted onto Pinus sylvestris var.mongolica at the Huangyugou Sand Control and Afforestation Farm in Keshiketeng Qi.Some Pinus koraiensis began bearing fruit in 2021.In the first half of 2023,most areas of Chifeng,including Keshiketeng Qi,experienced extreme drought,leading to a decrease in the yield of Pinus koraiensis cones.In October 2023,a line transect survey was conducted to investigate the growth and fruiting conditions of the grafted Pinus koraiensis.Results showed that using an empirical grouping method,fruits were classified into two groups based on whether the mature fruit length exceeded 11 cm.The average values of fruit length and diameter between the two groups showed significant differences,while other indicators did not.This indicates that the size of Pinus koraiensis cones is mainly influenced by genetic factors.Using cluster analysis,fruits were divided into three groups:large,medium,and small.Except for the variance in height growth of the scion in 2019 and 2023 and the number of mature fruits,the average values of six indicators,including the height of grafted trees with medium-sized fruits,rootstock crown width,graft junction height,scion crown width,height growth in 2020,and height growth in 2021,showed significant differences compared to large and small fruits.Under drought conditions,grafted trees with medium-sized fruits showed better vegetative growth than those with large or small fruits.Investigating the length,diameter,and quantity of mature Pinus koraiensis cones grafted onto Pinus sylvestris var.mongolica helps distinguish the gender type of Pinus koraiensis or select specific types for breeding.
万方数据
维普
