JOURNAL OF NANJING FORESTRY UNIVERSITY ›› 2023, Vol. 47 ›› Issue (6): 95-104.doi: 10.12302/j.issn.1000-2006.202112031

Previous Articles     Next Articles

Young growth rhythm, annual and density interaction effects and selection strategies of Picea abies clones

OU Yang1,2(), OUYANG Fangqun3,*(), SUN Meng3, WANG Chao3, WANG Junhui1,*(), AN Sanping4, WANG Lifang4, XU Na4, WANG Meng2   

  1. 1. State Key Laboratory of Tree Genetics and Breeding,Research Institute of Forestry, Chinese Academy Forestry, Key Laboratory of Tree Breeding and Cultivation of the National Forestry and Grassland Administration, Beijing 100091, China
    2. College of Forestry, Southwest Forestry University, Kunming 650224, China
    3. Beijing Botanical Garden, Beijing Floriculture Engineering Technology Research Centre, Beijing Laboratory of Urban and Rural Ecological Environment, Beijing 100093, China
    4. Forestry Research Institute of Xiaolongshan,Gansu Province,Tianshui 741022, China
  • Received:2021-12-17 Revised:2022-05-12 Online:2023-11-30 Published:2023-11-23

Abstract:

【Objective】 This reseach aims to select Picea abies varieties for reforestation in Xiaolongshan area of Tianshui of Gansu Province based on analyses of early growth and genetic traits. 【Method】 Using 267 P. abies clones of young Czech provenance as test materials, we evaluated the growth and clone repeatability of 4 to 9 years old spruce trees, and the relationship with year, then the elite clones were chosen. 【Result】 The average tree height of 9 years old spruce was (269.79±41.3) cm. The repeatability of the clones during the period of 4 to 9 years old was 0.45 to 0.69, and the high repeatability indicated that the clones had selection potential. Age-specific genetic variation in growth traits (tree height, diameter at breast height, crown width, shoot length and number of collaterals, etc.) differed significantly among blocks and clones with pronounced interactions between the two (variance component 20.37%-27.23%). Tree height growth was affected by age, block, clone, interactions between age and clone, and between block and clone with variance component ranking order from high to low: age (70.05%), followed by the interactions between block and clone (7.59%), and between age and clone (1.23%). Significant positive correlations among growth years were found for tree height phenotypic traits (0.61-0.95), genetic traits (0.62-0.97) and environmental variables (0.63-0.95). Ten clones were selected for reforestation in the Xiaolongshan area based on the relative genetic value of the 9-year-old tree height with an average tree height of 369.7 cm. The selection rate was 3.7%, and the actual genetic enhancement for tree height was 9.72%-16.89% with an expected genetic enhancement of 65.66%-107.88% at tree mature stage. The average tree heights of the selected clones were higher than the control clones in 4 to 9 years with a substantial variation in height growth among different years. The Finlay-Wilkinson model was used to analyze the stability of the mean tree height of clones from 4 to 9 years old. The better the growth of the clone, the higher the estimated value of stability, indicating that the clone was more unstable. Annual average tree height increment correlated positively with the annual extreme high temperature, and negatively with the annual rainfall. 【Conclusion】 P. abies clones have extensive genetic variation in growth traits, high repeatability, and are opted for selection. The 10 P. abies clones selected based on their genetic values of tree height at 9 years can be used for afforestation in the Xiaolongshan area of Tianshui, Gansu. Differences in extreme high temperature and average annual rainfall between years may account for the instability of the selected clones across tree ages.

Key words: Picea abies, clone, growth rhythm, genetic variation, stability, selection strategy

CLC Number: