农杆菌敏感小麦基因型的筛选研究

Screening of Wheat Genotype Sensitive to Agrobacterium tumefaciens Infection

基因型是影响农杆菌转化植物的主要因素之一,筛选对农杆菌敏感的小麦基因型对于进一步提高小麦转化效率具有重要意义.利用c58C1农杆菌菌系(含GUS基因)感染不同小麦品种的幼穗和幼胚,共培养后进行X-Gluc组织化学染色检测,以筛选对农杆菌敏感的小麦基因型.结果表明,83个小麦基因型的幼穗经农杆菌感染后,GUS基因表达率66.7%～82.8%,CA9924、北农49、西农2611、京冬11等基因型对农杆菌感染比较敏感,多数基因型对农杆菌感染不敏感.80个小麦基因型的幼胚经农杆菌感染后,GUS基因表达率在10.0%以上的基因型仅占3.8%,没有GUS基因表达的基因型多达71.3%,绝大多数基因型对农杆菌感染不敏感;当幼胚与农杆菌的共培养在滤纸上进行时,97H2169、轮选208、兰考906、扬麦6号等基因型对农杆菌感染非常敏感,GUS基因表达率达到50.0%～93.3%,没有GUS基因表达的基因型下降到36.8%.表明不同小麦基因型以及相同基因型的不同外植体对农杆菌的敏感性存在着显著差异,兰考906、扬麦6号、西农2611、京冬11等基因型是农杆菌转化小麦较为理想的受体材料;滤纸上共培养方式更有利于农杆菌对小麦外植体的侵染,GUS基因表达率平均比固体培养基共培养方式高16.6个百分点.

Some researches on the Agrobacterium-mediated transformation of wheat have been successfully carried out in recent years, but the transformation efficiency is still not good enough. Wheat genotype might be one of the most important factors in improving the transformation efficiency. For such a purpose, c58C1 Agrobacterium strain harboring a binary vector pPTN290 with nptII gene and GUS gene was used to infect different explants of different wheat genotypes which including 31 spring wheat genotypes and 59 winter wheat genotypes and collected from different domestic areas in this research. To evaluate the sensitivity of these genotypes to the Agrobacterium, the infected explants by Agrobacterhtm were tested by X-Gluc staining for GUS gene transient expression. The result showed that the inflorescences of CA9924, Beinong 49, Xinong 2611, Jingdong 11 were sensitive to the Agrobacterium infection, and GUS gene transient expression frequency was from 66.7% to 82.8%. The immature embryos of 97H2169, Lunxuan208, Lankao 906 and Yangmai 6 were sensitive to the Agrobacterium infection, and GUS gene transient expression frequency ranged from 50.0% to 93.3%. It was indicated that most genotypes were not sensitive to the Agrobacterium, whether to their immature embryos or to their inflorescences. The results also suggested that while the coculture step processed on paper. The GUS gene transient expression frequency on average could be increased 16.6% more than that prosessed on solid medium.