华南地区山地木麻黄种源试验与筛选

INTERNATIONAL PROVENANCE TRIALS OF CASUARINA JUNGHUHNIANA IN SOUTHERN CHINA

依据首次建立在华南地区的各含 2 8个种源的两片山地木麻黄种源试验数据 ,分析了 1～ 4a生树高、胸径、单株材积和保存率等 4个性状的方差分量、遗传变异系数和遗传力等遗传参数。结果表明树高、胸径、单株材积和保存率在地点间、种源间及种源×地点互作间均有显著或极显著差异。当不考虑种源×地点互作效应互作时 ,3～ 4a生性状种源广义遗传力 ,树高变幅为 11 0 0 %～ 13 80 % ,胸径为 3 32 %～ 5 5 5 % ,单株材积为 5 4 0 %～ 8 30 %。以用材林为培育目的 ,依据 4a生树高、胸径、单株材积和保存率计算的综合评定值大小 ,分别对两个试验的参试种源进行了排序和选优 ,以 2 5 %的入选率 ,每试验各有 7个种源入选。E96 8试验的优良种源为 1884 4、194 89、192 4 0、17877、194 91、194 90和 192 39;E96 6中优良种源为 192 38、1884 7、1885 3、17877、1895 0、1885 2和 1894 9。筛选后树高、胸径和单株材积可获得明显的遗传增益。参试种源树高、胸径、单株材积和保存率性状间均表现出极显著正相关。树高早期表型相关和遗传相关极其显著 ,可用于树高的早期预测。最后 。

The two international provenance trials of Casuarina junghuhniana Miq. were established in Zhangzhou, Fujian Province and Dianbai, Guangdong Province in southern China. The 28 seedlots of seeds all came from Australian Tree Seed Centre, CSIRO. A complete randomized block design was employed for each site, with 16 or 25 trees per plot and 4 blocks or replicates. From 1 to 4 years old, tree height ( H , m) and diameter at breast height ( DBH , cm) were measured, calculated single tree volume ( V ) and tree survival percentage ( S , %). The results showed that there were significant differences in all traits between sites, between provenances, and between interaction of provenance x site (G x E) , which indicated that those provenances were not only genetic variation in tree growth indexes at each site but also genotype x site interaction. Provenance broad heritability was calculated. Using H, DBH, V and S at 4 years, by the Multiple Objective Strategic Decision Analysis method, provenances in each trial was optimized and ranked. On the purpose of high wood yield in plantation, the selected provenance rate was 25% of the total seedlots in the trials. Then the 7 seedlots 19238, 18847, 18853, 17877,18950,18852 and18949 at Zhangzhou (E 966), and the 7 seedlots 18844, 19489, 19240, 17877, 19491, 19490 and 19239 at Dianbai (E 968), were screened out as better provenances. These seedlot comprehensive estimating index values ( Wi ) were significantly bigger than the mean value of the whole seedlots. Genetic variation coefficients and broad\|sense heritability ( H 2) of provenance in all traits were estimated from 1 to 4 years after planting. The early age\|age phenotypic/genetic correlation coefficients of tree heights from 1 to 4 years old, and between H, DBH, V and S traits were all.significant positive, which could be benefited to the early age\|age prediction for tree height, or indirect selection and comprehensive selection for provenance. Possible suitable areas of Casuarina junghuhniana provenances were predicted in southern China, by means of Booths model.