摘要
对两片包括 1 8个和 1 7个无性系试验林历年树高和胸径作了测量 ,分析了树高和胸径历年位次 ,表型和遗传相关 ,遗传力、遗传和环境方差随年龄增高的时间趋势 ,历年树高和胸径与最后一年测量中所计算的单株材积的表型和遗传相关等。看到无论树高还是胸径 ,早—晚龄的表型和遗传相关都是极显著的 ,但少数生长型和生长动态模式偏离常态的无性系影响着这些参数在树龄间的稳定性。认为杉木的适宜早期选择年龄在4～ 6a生时 ,但最好从 3a后开始采用两阶段逐步评价和选择的策略 ,第 1阶段先按树高初选 ,第 2阶段按胸径或单株材积做出决选 ,既保证了选择的可靠性 。
This paper deals with the appropriate traits and optimum age of early selection to improve individual volume of Chinese fir (\%Cunninghamia lanceolata\% Hook) through clonal selection. The estimated parameters of early selection were based on height and diameter at breast height (DBH) measured from two clonal trials, which included 18 and 17 clones respectively, and were as parts of a large scale clonal breeding program. At the same time, there were two kinds of CK in each trial, which came from a first generation seed orchard and a superior seed source respectively. In the spring of 1987 and 1988, one\|year\|old rooted cuttings and seedlings were planted with 5～6 trees in a row plot in randomized complete blocks, with 5 replications at 2 m×1.7 m spacing. Height was measured every year after planting for trial 1, and at the second year after planting for trial 2, while DBH was measured at the third year after planting for the two trials. The last investigation was taken in 1997 for trial 1 with 11\|year\|old and trial 2 with 10\|year\|old, and the individual volume of this year was calculated according to the standard volume table for Chinese fir. The genetic variances, heritabilities, genetic and phenotypic variation coefficients and juvenile mature correlations of height and DBH were estimated. Meanwhile, the genetic and phenotypic correlation between the height, DBH measured at different ages and volume calculated were also estimated to determine the best indicator for early selection. The result showed that there were significant differences (P<0.0001) among the test materials, and very strong and stable juvenile\|mature genetic correlations, and also high clonal heritabilities for height and DBH at different ages, and significant correlations among height and DBH at 3～4 years after planting and volume calculated. So the clonal selection or elimination of Chinese fir clones might be carried out reliably arround 3～4 years after planting. Since heritabilities of DBH and juvenile\|mature genetic correlations of DBH with individual volume were higher than that of height at the same year, the efficiency of early phenotypic selection based on DBH was greater than that of height. The paper also noted that some mistakes could be occured in early selection because of some clones with special growth type and growth pattern such as \!slim clones' and 'stout clones' or \!upgrading performers' and \!degrading performers'. So, the early selection could be carried out by the strategy of two stages selection, the first stage selection may be conducted with height at the age of 3\|year\|old and the final selection completed with DBH during the period of 4～6 years after planting.
出处
《林业科学》
CAS
CSCD
北大核心
2000年第z01期62-69,共8页
Scientia Silvae Sinicae
关键词
杉木
无性质
遗传力
早期选择
育种
树高胸径
Cunninghamia lanceolata Hook, Clonal test, Juvenil mature correlation, Heritability, Early selection
