3种北美冷杉的核型研究

本文首次报道３种北美冷杉Ａｂｉｅｓ ａｍａｂｉｌｉｓ、Ａ．ｇｒａｎｄｉｓ和Ａ．ｌａｓｉｏｃａｒｐａ的根尖体细胞核型、染色体参数及核型模式图。核型公式分别是Ｋ（２ｎ）＝２４＝１６ｍ（４ＳＣ）＋８ｓｍ、１４ｍ（２ＳＣ）＋１０ｓｍ和１８ｍ（４ＳＣ）＋６ｓｍ，染色体相对长度组成为２ｎ＝２４＝２Ｌ＋１２Ｍ２＋６Ｍ１＋４Ｓ、２Ｌ＋１２Ｍ２＋８Ｍ１＋２Ｓ和２Ｌ＋８Ｍ２＋１２Ｍ１＋２Ｓ。均为２Ａ核型类型。文中还讨

A KARYOTYPIC STUDY ON THREE SPECIES OF ABIES (PINACEAE) FROM NORTH AMERICA

The present paper deals with the karyotype analysis of three species of the Abies (Pinaceae) from North America including A.amabilis Doug.ex Forbes., A.grandis Lindl.and A.lasiocarpa (Hook.) Nutt.Their morphology of somatic chromosomes in root tip cells,chromosome parameters and diagrams are published for the first time.The karyotype fomulas of the species are K(2n)=24=16m(4SC)+8sm,14m(2SC)+10sm and 18m(4SC)+6sm respectively.Their chromosome complements are 2n=24=2L+12M2+6M1+4S,2L+12M2+8M1+2S and 2L+8M2+12M1+2S according to the standard defined by Kuo et al.(1972) based on relative length.They belong to 2A type of stebbins karyotypic asymmetry.The karyotypes of A.amabilis and A.grandis are reported for the first time.The evolutionary positions of the three species and the sections they belong to are also discussed in the paper.