伞形科植物染色体数目报告

本文报道了伞形科15属24种和交种的染色体数，其中18个种和变种是首次报道。研     究表明， 我国天胡荽属 (Hydrocotyle L．)是伞形科多倍体比较普遍的类群。柴胡属(Bupleu-     rum L.)分别有4、6、7、8等基数，茴芹属(Pimpinella L.)的毛果组(Sect. Tragium)和光     果组(Sect．Tragoselinum)的代表种类的基数分别为9和10，因此，染色体基数可作为深入     研究某些属内种类演化的细胞学资料之一。思茅独活(Heracleum henryi Wolff)的花粉母细    胞在终变期时出现了4体环，说明结构杂合体可能是伞形科种类分化的一个因素。

A Report on Chromosome Numbers of Chinese Umbelliferae

This is the third report of chromosome numbers of Umbelliferae after 1981 and 1985, which deals with 24 species and varieties of 15 genera including 2 endemic genera and 10 endemic species, and most of them are distributed  in southwestern China.   Of them, 18 counts are newly reported.  The taxonomic significance is discussed  in relation with their basic numbers, translocation heterozygote and polyploids.  It is considered that polyploids are wide-spread in Hydrocotyle L. 4, 6, 7, 8 are the basic numbers  of Bupleurum L. which pro- vides the cytological evidence  for further  study on their evolutionary process. n=9 and  10 occurrespectively in two different sections of Pimpinella L. and their basic numbers may be used for classification at the section level.  The ring formation of four chromosomes at dia- kinesis of Heracleum henryi Wolff reveals that translocation heterozygotes is one of the factors in specific differentiation of Umbelliferae.