水曲柳自然群体子代测定及优异群体选择

Progeny Test on the Natural Populations and Selection of Excellent Populations from Fraxinus mandshurica

水曲柳(Fraxinus mandshurica Rupr.)为主产于中国东北东部山地的古老第三纪孑遗植物之一,对研究第三纪植物区系及第四纪冰川期气候具有重要的科学价值。为了合理地利用水曲柳的自然遗传资源,提高良种的科技附加值,以自然群体自由授粉子代测定林为对象,采用固定标准地定位观测的方法,在子代测定、生长动态及遗传效应分析的基础上,探讨群体及自由授粉子代的树高和胸径的遗传变异,系统分析了生长性状的遗传力和遗传增益,并从中选择生长、抗逆性和适应能力兼优的群体。结果表明:东北东部山地水曲柳自然群体间的生长性状存在极显著的差异,其中,树高性状的变异较小,而胸径性状的变异却较大,平均变异系数分别为22.99%和41.37%。另外,群体内自由授粉子代间生长性状的差异亦极显著,且子代与区组的交互作用明显。水曲柳的生长性状受遗传基因的控制程度较强,遗传增益较大,树高和胸径的遗传力分别为0.825和0.781,遗传增益分别为15.16%和25.85%,因此,以生长性状为主要评价指标,兼顾各种影响因素,确定山河屯[SHT]与兴隆[XIL]为生长、抗逆性和适应性兼优的群体,广泛应用于多世代遗传改良育种中。

Fraxinus mandshurica is one of the ancient relict flora species originated from the Tertiary period, which mainly produced in the eastern mountain to Northeast China and had an important scientific value for the study of the flora in the Paleogene and the climate in Quaternary ice age. By the method of positional observation of fixed standard fields, this thesis performed on discussing the genetic variation of the tree height and DBH from the natural populations and its open-pollinated progenies, and analyzing systematically the heritability and the genetic gains in quantity characters on the basis of analyzing the growth dynamic, the progeny test and its heredity effects, then screened out excellent ones from these populations. The research results had showed that there were greatly significant differences on the quantitative characters among the natural populations, and the coefficient of variance from the tree height [22.99%] was smaller, but its DBH [41.37%] was larger. On the other hand, there were greatly significant difference among its open-pollinated progenies of the tree height and DBH within natural populations too, and hold great interaction between these progenies and the blocks. Meanwhile, the growth characters had strong heritability, high genetic gain, and remarkable heredity effects. The heritability of tree height and its DBH were 0.825 and 0.781, and the genetic gain were 15.16% and 25.85%, respectively. Therefore, SHT and XIL were determined to be excellent natural populations both in the growth, resistance and adaptation with growth traits as the main evaluation index, which was applied in the advanced generation improvement breeding.