茎尖转化法转基因小麦后代的遗传特性分析

Genetic Characters of Progenies of Transgenic Wheat by Shoot Apical Point Transformation

为了探讨农杆菌转化微创芽生长点法获得的转基因小麦后代的遗传特性,以3个世代的转基因小麦后代为材料,通过抗性筛选、PCR和PCR-Southern blot等方法分析外源基因遗传在T_2、T_3、T_4中的遗传分离情况。结果表明:T_2代33个株系中外源基因完全丢失的株系占61%,其余39%的株系能够检测到外源基因,但分离比例分散偏离了孟德尔遗传分离规律;T_3代42个株系中检测不到外源基因的株系占55%,能检测到外源基因但分离比例复杂的株系占43%,符合孟德尔分离定律占2%;T_4代8个株系中检测不到外源基因的株系占25%,能检测到外源基因但分离比例复杂的株系占50%,转基因植株与非转基因植株的分离比例符合孟德尔分离定律占25%。可见,利用农杆菌转化微创芽生长点法获得的转基因小麦后代中,外源基因丢失的比例较高,转基因植株与非转基因植株的分离多不符合孟德尔分离比例,但随着世代的增加,外源基因遗传稳定性有所提高。

In order to investigate the genetic characteristics of transgenic wheat progenies,which were obtained by shoot apical point pathway. We used three generations of transgenic wheat progeny as material, the genetic characteristics of exongenous gene in T2, T3 and T4 were analyzed through the re- sistance screening, PCR, PCR-and Southern blot method. The results showed that in 33 strains of T2, the exogenous gene completely missing strains accounted for 61%, and the exogenous gene ac- counted for 39%, it could be detected, but it deviated from Mendel＇s genetic law of segregation. In 42 strains of T3, the exogenous gene completely missing strains accounted for 55% ; the exogenous gene accounted for 43%,it could be detected but deviated from Mendel＇s genetic law of segregation; the exogenous gene separation ratio was consistent with Mendel＇s genetic law of segregation, accounting for 2 %. In 8 strains of T4,2 strains could not be detective exogenous gene; 4 strains could be detected but the segregation ratio of exogenous gene was complex; the segregation ratio of the 2 strains of transgenic plants and non-transgenic plants in accordance with Mendel＇s law of segregation. In conclu- sion,the progenies of transgenic wheat by shoot apical point transformation, the separation of trans- genic plants and non transgenic plants were dispersion,genetic stability of foreign genes increased sig- nificantly with the multiplication of selfing generation.