关键词: 沙参属, 染色体数目, 核型

Abstract: In this paper, chromosome numbers and karyotypes of five species of Adenophora are reported for the first time. The species under study are native to China. The results are as follows: 2n= 34= 28m+4sm(2sat)+2st(2sat) for A. borealis; 2n= 34= 26m(4sat)+6sm+2st or 2n = 34+1 B = 26m (4as t)+6 sm+2 st+ 1B for A. w ulingshanica; 2n = 34 = 26m (2sat)+6sm+2st or 2n = 34+1B = 26m (2 sat)+6 sm +2 st+ 1B for A. petiolata, 2n = 34 = 26m+4sm (2 sat)+4 st or 2n= 34+2B = 26m+4st(2sat)+4st+2B for A. lobophylla; 2n= 34= 28m(2sat)+4sm+2st for A. potaninii. The karyotypes of these species are consistent with those of the species previously re-ported. The chromosomes are small, with the majority of them being "m" ones; and a pair of sat-chromosomes and a pair of " st" chromosomes are always present. The centromeric terminalization value of chromosomes is 58.4%~ 62.0%, which shows high symmetry of karyotpyes in this genus. The special karyotype of A.lobophylla. together with its morphological characters, suggests that it is more advanced than the other species and its position is dicussed.

Key words: Adenophora, Chromosomal number, Karyotype