Progeny Test And Analysis Of Half-sib Families Of Loblolly Pine

With the development of forestry in Fujian Province, it is necessary to improve the mono-structure of coniferous forests, to recover the ideal forestry ecosystem and to reform the forestry industry system. Therefore, twenty five 2nd generation Loblolly pine half-sib families were introduced by Fujian province under help of International Paper Company(IP), USA in 1997. The progeny testing of Loblolly pine families were layouted in 7 multi-site through Fujian Province in this dissertation, and Slash Pine introduced early and native Mason Pine were picked up as CK. Ten years data was used for growth evaluated, genetic variation analysis and family selection, for different regions. Twevle years growth and wood properties data was used for correlation analysis in Nanyu test site. The main results and conclusions are presented as follows:1. The 2nd generation Loblolly Pine families introduced from International Paper Company grows faster than early-introduced Slash Pine and native Mason Pine on all the test sites in Fujian province at age ten. By synthesizing clustering analysis, the performance of the 25 families on all sites could be divided into 3 categories: the best, middle and poor, the actual gains of volume for the best and middle categriy were 22.02%, 14.34% over the Slash Pine respectively, and 27.16 %, 19.16% compared with Mason pine, respectively.2. There were significant differences among families on the height, DBH and volume, and which were mainly controlled by moderate genetic effect. The variation range of volume was varied from 7.90% to 17.13%.3. Involved in the tests, the average breeding values of 25 Loblolly Pine families were 6.9904, 13.1521 and 0.0574. There were five fast-growing families, No.5, 6, 8, 16 and 18, were selected based on their breeding value. There were five families, No.1, 5, 6, 8, 10 and 21, were selected as superior family based on the characteristics of fastgrowing and stability. However, the families, No.7, 17, 18, 19, 20, 22 and 23, were fast-growing but instability, which only can grow fast under fine environments.4. There were very significant positive correlation between phenotype and genotype on height, DBH and volume in Nanyu test site. The negative phenotype and genotype correlation coefficient found between the growth traits and wood basic density and micro fibril angle. And no significant correlation was to be found between wood basic density and micro fibril angle.5. Finally, five fast-growing families and eighty individuals were selected at Nanyu. And 70% of the individuals were from these fast-growing families. The synthesizing selection index on volume, wood basic density and micro fibril was: I=92.3198X₁ +59.8303X₂+1.14307X₃. The superior families were No.6, 9, 19, 22 and 23 based on the index.