草莓组培苗体细胞无性系变异研究

组培过程中变异的普遍性,显著影响植物的遗传稳定性,限制组培技术在农业生产上的应用。草莓组培苗已在农业生产中广泛应用,但变异却时有发生,严重影响其生产效益。因此,如何有效控制变异的发生是草莓及其他组培快繁技术中亟待解决的问题。笔者分析了影响组培变异的主要因素有外植体类型、基因型、培养基中激素种类和配比、继代培养的时间和次数,和内在遗传机理如染色体异常、转座子活化和基因突变等,针对这些影响因素,建议选择幼嫩的外植体、优化培养基配方、控制增殖系数和继代次数以及选择合适的光照和温度等培养条件,控制组培过程中变异的发生。同时,利用形态观察和RAPD、SSR等技术对组培苗进行检测,及时剔除变异组织或变异植株,减少变异对生产的不利影响。通过总结草莓组培中变异发生的原因和有效控制变异的途径,为包括草莓在内的植物脱毒组培快繁技术的健康发展提供参考,同时,对变异的深入认识,为植物品种改良和新品种的选育提供了新思路。

Strawberry Plantlets Somaclonal Variation

Variations are easily induced in tissue culture of plants. They significantly affect the genetic stability of plants, and limit the application of tissue culture technology in agriculture. Strawberry in vitro seedlings have been widely used in agricultural production. However, the variations often occur in tissue culture of plant, which seriously influence the agricultural production efficiency. Therefore, it is an urgent problem to effectively control the occurrence of the variations in vitro rapid propagation of strawberry and other plants. The main factors affecting the occurrence of the variations were analyzed. These factors included explant types, genotypes, the types and proportion of different hormones in the medium, the time and times of subculture. And the inherent genetic mechanism of the variations had chromosomal abnormalities, transposon activation, gene mutation and so on. In order to effectively control the variation occurrence in tissue culture of strawberry, it was suggested to select the young explants, optimize the culture medium formula, control the multiplication coefficient and the subculture times, and culture the tissues under proper light and temperature conditions. Meanwhile, using the methods of morphological observation, RAPD, SSR and so on to detect the variations in tissue culture seedlings could eliminate the variant seedlings and reduce the adverse effects of the variant plants to production. By summarizing the causes and the effective controlling ways of the variation of strawberry in vitro, it would provide valuable reference for the healthy development of plant virus-free tissue and rapid propagation of plants including strawberry. Moreover, the deep understanding of variation would provide a new way for the improvement and breeding of new varieties.