小麦不同外植体离体培养及转化效率的比较研究

小麦基因枪法遗传转化中幼胚组织培养有很强的基因型依赖性．这在很大程度上限制了转基因小麦的广泛应用。为了建立克服基因型障碍的小麦高效再生系统．促进转基因小麦的规模化应用，对15个小麦基因型的幼穗、幼胚两种外植体的愈伤组织诱导率、绿苗分化率进行了比较研究。结果表明，各基因型愈伤组织诱导率在两种外植体之间无差异，但幼穗外植体产生的愈伤组织质量好于幼胚。15个基因型幼穗外植体的绿苗分化率均高于其相应的幼胚外植体绿苗分化率，表明幼穗是很好的外植体材料。对其中H6756和H311两个基因型不同外植体所形成的愈伤组织进行了基因枪转化，姑果表明，幼穗受体的基因转化效率明显高于其相应幼胚受体的基因转化效率。

A Comparative Study on the Tissue Culture and Transformation Efficiency of Different Explants in Wheat (Triticum aestivum L.)

Wheat transformation via microprojectile bombardment with immature embryo culture strongly depends on the genotypes. This problem restricts the wide application of transgenic wheat in a great extent. Optimization of regeneration system of wheat to overcome the genotype obstacle has great significance in promoting the application of transgenic wheat to a large scale. Young spikes and immature embryos of 15 wheat genotypes were tissue-cultured to study and compare the callus induction rates and green plantlet differentiation rates. The results showed that there was no difference in callus induction rates between young spikes and immature embryos of all the involved genotypes, but the quality of callus from young spikes was better than that from immature embryos. The green plantlet differentiation rate of young spikes was higher than that of immature embryos in all the 15 genotypes, which indicated that young spike was a good explant in wheat tissue culture. Gene transformation was conducted by biolistic bombardment to callus from both young spikes and immature embryos of H6756 and H311. As a result, the genetic transformation efficiency of young spike acceptor was obviously higher than that of immature embryo acceptor. The present study provided experimental basis for widening and optimizing the acceptor system of wheat transformation by biolistic bombardment.