伊贝母愈伤组织在继代培养过程中的染色体变异和分化频率的研究

本文报道了伊贝母愈伤组织在不同培养基上继代培养的的染色体变异和分化频率。结果表明,随着继代培养的进程,二倍体细胞频率逐渐减少。亚二倍体和超二倍体细胞频率迅速增加。同时还观察到比率不等的亚单倍体、单倍体,超三倍体和超四倍体细胞。于是培养物最终变成为只有少量整倍体而多数为非整倍体染色体数的混倍体细胞群体。不同培养基对染色体变异的效应是2,4-D+KT>IAA+KT>NAA+KT。分化频率随继代次数的增加而下降。同时还观察到了各种类型的染色体结构变异和有丝分裂异常。根据试验结果,对继代培养中染色体变异的原因以及与分化频率的关系进行了讨论。

STUDY OF CHROMOSOME VARIATION AND DIFFERENTIATION FREQUENC IN CALLUS SUBCULTURES OF Fritiliariae pallidiflorae

The paper reports chromosome variation and differentiation frequency of in vitro callus subculture of F. pauidifiorae in different hormonal regimes. The results showed that the frequency of diploid cells is decreasing, the frequency of hypodiploid and hyperdiploid cells is increasing rapidly with the age of the culture. Hypohaploid, haploid, hypertriploid and hypertetraploid cells were observed with diff- erent ratios. Thus the culture became mixoploid having both few the euploid and more aneuploid chromosome numbers. The effect of different medium on chromosomal variation is 2, 4-D+KT>IAA+KT >NAA+KT. The differentiation frequency is declining with the age of the subculture. The changes of chromosome structure and mitotic irregularities was observed in callus cells. In accordance with results of experiments, the possible reason for chromosome variation and relations between variation of chromosome numbers and callus differentiation in subculture were discussed.