金钱松染色体核型的研究

Karyotype Studies of Pseudolarix amabilis

本文研究了珍稀植物金钱松Ｐｓｅｕｄｏｌａｒｉｘａｍａｂｉｌｉｓ（Ｎｅｌｓｏｎ）Ｒｅｌｄ．的核型，其核型公式为Ｋ（２ｎ）＝４４＝２４ｍ（Ｍ）＋１６ｓｍ＋４ｓｔ．第４，７，８，９，１２，１３，１４，１５，１８，１９，２１，２２对为中部着丝点染色体，第１，３，６，１０，１１，１６，１７，２０对为近中着丝点染色体，第２，５对为近端部着丝点染色体．根据Ｓｔｅｂｂｉｎｓ的染色体核型的不对称性类型，金钱松属于“２Ｂ”型．

A karyotype analysis of P.veudolarix amabilis(Nelson) Reld. herewith presented is being the first time, and the chromosomes in root tip cell was found to be 2n=44. The somatic complement showed a slight variation in size, the 4, 7, 8, 9, 12, 13,14, 15, 18, 19, 21 and 22th pairs had median centromeres, the 1, 3, 6, 10, 11, 16,17 and 20th pairs had submedian constrictions, the 2 and sib pairs had subacrocentric constrictions. According to the classification systems given by Levan et al, the karyotype formula of the species is therefore K (2n)=44=24m(M)+16sm + 4st. It belongs to '2B' type of karyotype symmetry.