马尾松形态解剖特征的地理变异

<正>马尾松(Pinus massoniana Lamb)在植物分类学上属松科(Pinaceac)松属(Pinus)双维管束松亚属(Subgen.Pinus)的一种。它是我国松属中分布最广、数量最多的一种主要用材树种。在南方各省(区)森林蓄积中,马尾松约占半数;并占全国针叶树林面积的14.9％,蓄积量的6.1％。马尾松在我国国民经济发展中是一项极其重要的资源。

GEOGRAPHICAL VARIATIONS IN THE MORPHOLOGY AND ANATOMY OF PINUS MASSONIANA

This paper reports on our research into the geographical variations in the morphology and anatomy of Pinus massoniana in 1979-1983. The main conclusions can be summarized as follows.1. Our research results prove that the variations in the properties of Pinus massoniana are objective and heritable, and are significant in differentiating sub-populations. 2 . Of the ten characters studied, variations in characters such as the number of needle resin canals, the rate of needle bundles, the disk's number and total sum of lateral branches per year and the insertion condition of winter-buds are obvious, having the evident tendency of south-north gaographical divergence, with negative correlationships between the great majority of the characters and the latitude,On the contrary, there exists very little or almost no west-east divergence in all the characters with the exception of a positive correlationship between the resin canal number and the longitude. 3 . Analyses of correlationships show that Pinus massoniana at low latitudes in the south produces tips for several times every year, forms 3-4 rings of lateral branches and more lateral branches, turns out tight winter-buds, low rate of the two-needle bundles, high rate of three-needle bundles, darkgreen needles and generally increased resin canals. However, Pinus massoniana at high latitudes in the north is quite different. 4 . Variations in characters of plants from different provenances are significant; all of them reach 1% level. Variations between plants from different provenances of near latitudes and longititudes are not obvious, but as the geographical distance, especial the north-south distance, increases, variations in many characters become more and more evident. This indicates that geographical variations in Pinus massoniana characters belong to gradual population variation trends.