The type, position and age effect on the cutting reproduction of Picea crassifolia and its rooting mechanism in the Qilian Mountains  

作　　者：Jianjun Kang Wenzhi Zhao Ming Zhao Guangyu Li Jiqiang Zhang Zhisheng Zhang 

机构地区：[1]Linze Inland River Basin Research Station,Key Laboratory of Inland River Basin Ecohydrology,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Science [2]Gansu Research Academy of Forestry Science and Technology [3]Haxi Natural Protection Station,Administration of Gansu Qilian Mountains National Nature Reserve

出　　处：《Journal of Forestry Research》2015年第4期993-1002,共10页林业研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.31360086);the grant from the major state basic research development program of china(973 program,No.2013CB429903)

摘　　要：Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its rooting mechanism, cuttings of P. crassifolia with different cutting types （softwood, hardwood and root）, positions （top, upper, middle and bottom） and ages （7, 10, 15, 20, 25 year-old） were cultivated in a field experiment. One- year old softwood and hardwood cuttings were collected from 7-, 10-, 15-, 20-, and 25 year-old healthy ortets to analyze the changes from endogenous hormones and organic nutrients. Results indicate that the softwood cut- tings （0.5-1.0 cm in diameter） from upper branches of 15 year-old ortets shows better growth performance by improving rooting indexes, including a significant increasein rooting rate and a decrease in basal rot rate. Concomi- tantly, increasing rooting quantity and root length also increased. It is noteworthy that the high rooting rate of P. crassifolia cuttings due to its ability to accumulate high concentrations of indole-3-acetic acid （IAA） and total carbon （TC） rather than abscisic acid （ABA） and total nitrogen （TN）. The rooting rate was mainly regulated by the IAA/ABA and TC/TN ratio. In summary, our results suggest that the softwood cuttings （0.5-1.0 cm in diameter） from upper branches of 15 year-old P. crassifolia can be considered as an effective strategy to improve cutting rooting rate, and the IAA/ABA and TC/TN ratio was one of the main factors limiting the cutting rooting rate of P. crassifolia.Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its rooting mechanism, cuttings of P. crassifolia with different cutting types （softwood, hardwood and root）, positions （top, upper, middle and bottom） and ages （7, 10, 15, 20, 25 year-old） were cultivated in a field experiment. One- year old softwood and hardwood cuttings were collected from 7-, 10-, 15-, 20-, and 25 year-old healthy ortets to analyze the changes from endogenous hormones and organic nutrients. Results indicate that the softwood cut- tings （0.5-1.0 cm in diameter） from upper branches of 15 year-old ortets shows better growth performance by improving rooting indexes, including a significant increasein rooting rate and a decrease in basal rot rate. Concomi- tantly, increasing rooting quantity and root length also increased. It is noteworthy that the high rooting rate of P. crassifolia cuttings due to its ability to accumulate high concentrations of indole-3-acetic acid （IAA） and total carbon （TC） rather than abscisic acid （ABA） and total nitrogen （TN）. The rooting rate was mainly regulated by the IAA/ABA and TC/TN ratio. In summary, our results suggest that the softwood cuttings （0.5-1.0 cm in diameter） from upper branches of 15 year-old P. crassifolia can be considered as an effective strategy to improve cutting rooting rate, and the IAA/ABA and TC/TN ratio was one of the main factors limiting the cutting rooting rate of P. crassifolia.

关 键 词：Picea crassifolia Kom TYPE Positionand age effect Cutting reproduction Rooting rate HORMONES Organic substances 

分 类 号：S791.18[农业科学—林木遗传育种]