本文由陕西省科技统筹创新工程计划项目2014KTCL02-04、陕西珍贵用材树种质资源培育关键技术研究项目20150210169和国家科技支撑计划项目2012BAD22B030204资助,This work was supported by the Overall Planning Project of Science and Technology Innovation in Shaanxi Province 2014KTCL02-04,the Key Technology of Resource Cultivation of the Valuable Wood in Shaanxi 20150210169 and the National Science&Technology Support Plan of China 2012BAD22B030204.