罗布麻和大叶白麻染色体核型分析

本文采用不同的预处理方法、盐酸解离时间及染色条件，对罗布麻（Apocynum venetum）和大叶白麻（Poacynum hendersonii（Hook．f）Woodson）离体根尖染色体分裂相的数目、染色体收缩程度、分散度以及着色深度进行了研究．对罗布麻和大叶白麻的核型进行了对比分析．结果表明：最佳的处理方法为：0．002mol／L8-羟基喹啉室温下处理根尖3h；卡诺液固定24h；1mol／L盐酸60℃下解离根尖15min；改良石炭酸品红染色24h后压片．罗布麻根尖染色体的核型公式：2n=2X=24=4m＋10sm＋8st＋2t；大叶白麻根尖染色体的核型公式：2n=2X=24=10sm＋12st＋2t．

Karyotype Analysis of Apocynum venetum and Poacynum hendersonii

The chromosomes from the root tips of （Hook. f） Woodson were studied in this paper.Cut Apocynum venetum Linn. and Poacynum hender sonii the root tips,then the different pretreatment methods were used, dispersion time and dyeing conditions were designed,the number of division phase,contraction, dispersion and dyeing effect of the chromosomes were observed.The karyotype of A. venetum and P. hendersanii were compared and analyzed.The results showed that the optimal means were to treat root tips with 0.002 mol/L 8-hydroxyquinoline for 3 h in room temperature, fixation root tip in carnoy＇s fluid for 24 h, dissociation root tip in 1 mol/L hydrochloric acid at 60℃ for 15min, stain root tip with modified phenols magenta dyes for 24 h, then squash. The karyotype formulas of the A. venetum is 2n = 24=4m＋10sm＋8st＋2t, the karyotype formulas of the P. hendersonii is 2n = 24 = 10sm = 12st ＋ 2t.