Technology Optimization of the Preparation of Chromosomes in Strobilanthes Cusia

By taking the meristem of Strobilanthes cusia cultivated in Putian as the material and using the conventional method, the effects of different sampling sites, sampling time, pretreatment with different reagents and dissociation time on the preparation of chromosomes in Strobilanthes cusia were studied, and the karyotype was analyzed. The results showed that:by taking the root apical meristem as the material, the root apical meristem was sampled at 8:00 and 8:30 a.m., pretreated with 0.1% colchicine solution at room temperature for 0.5 h, fixed with Carnoy for 4 h, and then bathed with 1 mol·L^-1 hydrochloric acid at 60℃ for 8 min, and stained with carbol fuchsin for 8 min, thus the chromosomes with good dispersion and clear shape could be obtained. The karyotype analysis showed that there were 32 chromosomes in Strobilanthes cusia. The karyotype formula of Strobilanthes cusia was 2x=2n=32=4sm+28m, the karyotype was 1 B, and the asymmetry coefficient was 59.54%. It indicated that the evolution rate of Strobilanthes cusia cultivated in Putian was slow in the relatively stable natural environment.