两种凤仙花多倍体的诱导

Identification of Colchicines-induced Polyploid Plants in Two Species of Impatiens balsamina

以凤仙花和茶花凤仙为试材,研究秋水仙素处理质量分数和时间对2种试材的多倍体诱变效应,通过植株形态特征、气孔数量及大小、染色体数目的观察进行倍性鉴定。结果表明,用w=0.5%的秋水仙素处理72~96 h的植株材料变异率较高,其中以0.5%秋水仙素处理96 h凤仙花的变异率最高,达29%。染色体压片检查表明,四倍体染色体数为2n=4x=28,二倍体对照为2n=2x=14。四倍体叶片长、宽、厚均增大,气孔密度减小,气孔保卫细胞增大,花径增加、花瓣增多,单朵花观赏价值显著提高。

The effects of colchicine concentration and treatment time duration on the chromosome doubling of the seedlings in two species of Impatiens balsamina have been conducted in this study,and the ploidy level was identified by morphological trait,stoma size and chromosome number.The results showed that treated two species of I.balsamina with 0.5% colchicine for 72-96 h led to a high mutation rate,and the highest mutation rate（up to 29%） was achieved in the I.balsamina by treatment of 0.5% colchicine for 96 h.Two tested species of I.balsamina have obtained a number of tetraploidy plants.The chromosome number of mutated plants was 2n=4x=28,while that of the control plants was 2n=2x=14.The tetraploid plants exhibited some morphological and cytological variations,including larger and thicker leaves,darker leaf color,larger stomata and fewer stomata per unit area.The ornamental value of single flower had also been greatly improved by increasing of flower diameter and petals number.