Study on Comparative Testing and Selection of Cunninghamia lanceolata Clones

A comparative experiment with 182 clones of Cunninghamia lanceolata introduced from Guangdong,Guizhou,Hunan provinces and other localities or bred in local areas of Guangxi was conducted.The result showed that there were significant genetic variations among the tested clones,and that the growth rate of the most tested clones,especially the clones introduced from outside of Guangxi,was lower than the local clones as control.The planting stage was significantly correlated to the growth rate and other indexes,the highest coefficient reached 0.988.Compared with clones introduced from other places,the genetic stability of clones selected and bred in Guangxi fluctuated more,and the final selection would take a longer duration,the early-stage selection was riskier for wrong selection or leaky selection with odds of 44.44% and 29.63% respectively.Taking standing volume as the main property index of Q-type sample clustering for each clone tested,and integrating with comprehensive judging analysis,27 clones such as Guangyun No.5,Liu No.327 and Hunan No.46 were screened out for their remarkable growth rate.