Cutting Position Effects And Rooting Characteristics Of Selected Clones From Platanus Occidentalis L. Provenance Testing

In this study,54 clones are selected both among and within provenience/families. All the selected clones are taken as experimental materials to study rooting character. And the forty seven open pollination Platanus occidentalis families were introduced from United States of America. The main conclusions are as follows:(1)The survival rates are extremely different in various clones. Through statistical analysis, we find that SJ has excellent rooting ability, NY and BHS choice are moderate, and SX has the worst rooting ability.(2)The survival rates in different parts of grain from various clones'branches have very significant differences. The most significant one is at the base of the cuttings with the survival rate of 43.89%; the next is the central part, and the survival rate is 29.2%, which is a bit of different from the base; the last one is the top part which is poor with the survival rate of only 14.91%, which is not appropriate for cuttings.(3)The survival rates differ greatly among various clones from the same family, the fact of which demonstrates that environmental factors have close relationship with the survival rate. The dependency analysis shows that apart from the sea level (Fvalue=0.9), other climate factors have an important effect on the survival rate, including relative humidity, which is the most influential effect, and F value reaches 23.89; in frost-free days, it relatively has little impact, only 5.14.(4) Judging from the origin place of Platanus occidentalis, the clones with higher survival rate are those introduced from Mississippi and Alabama, while the clones introduced from Louisiana have lower survival rate. The analysis on the relationship between survival rate of various clones with geographical, climate factor in original place shows:Introduction of the origin of correlation coefficients of latitude and survival rate reached significant level, longitude and correlation coefficients of survival rate reached a significant level, and the altitude of the introduced origin with survival rate is a negative correlation (coefficient 0.0505), longitude is a positive correlation (coefficient of 0.14171).(5)The analysis of annual clone seedling height, ground diameter, the number of leaves and other rooting characters shows:From the point of all the different clones in seedling height, ground diameter and leaf number in rooting time, different groups,different clones and between different location areas reached the very significant level.(6)Through survival rate of various clones and annual growth, we initially select BHS29,SJ31,SJ8,BHS36,DY36,SX36,SJ36,SJ10,NY38,NY44,BHS18,SJ7,DY16 as good clones.