在分離克隆抗白葉枯病基因Xa23研究中獲得大量轉(zhuǎn)基因水稻材料.為了系統(tǒng)研究轉(zhuǎn)Xa23基因水稻的抗病穩(wěn)定性和遺傳模式，本文通過逐株進(jìn)行抗白葉枯病接種鑒定、PCR和Southern blot分子檢測，對一批轉(zhuǎn)Xa23基因水稻植株進(jìn)行了T0代到T2代的跟蹤分析.結(jié)果表明，Xa23基因的整合和表達(dá)，使感病受體品種牡丹江8號獲得抗病性.由于Xa23基因捕入受體基因組的位點不同，同是單拷貝插入的轉(zhuǎn)基因T0代抗病植株，其抗病程度有明顯差異.T0代植株的抗病程度，可以準(zhǔn)確、穩(wěn)定地遺傳到T1代和T2代.單拷貝轉(zhuǎn)基因植株分離群體的抗感植株分離比接近3:1，表明轉(zhuǎn)Xa23基因遵循盂德爾單基因遺傳模式.已獲得2個純合的單拷貝轉(zhuǎn)基因抗病株系，它們的抗病程度稍有差別，將用于外源基因插入位置效應(yīng)分析和雜交稻抗病育種.
Transgenic rice plants were previously generated by Agrobacterium-mediated transformation during our research onmolecular cloning of Xa23 gene, a bacterial blight (BB) resistance gene from the wild rice species Oryza rufipogon. To investigatethe stability and inheritance of the transgene and its corresponding BB-resistance phenotype, more than 350 Xa23-trangenic riceplants from T0, T1, and T2 generations were subjected to BB-pathogen inoculation, PCR and Southern blot analysis for the transgene.Results showed that, Xa23 gene was incorporated and expressed in the genome of the susceptible receptor rice variety Mudanjiang8 that acquired BB-resistance. Due to the difference of the transgene insertion sites, T0 plants with single-copy insertionperformed quite different degrees of resistance and their resistance was accurately and stably inherited to T1 and T2 generations.We also observed that the transgene in the single-copy insertion transgenic lines inherited following the Mendelian rules. Twohomozygous, single-copy insertion transgenic lines with different resistance degrees have been obtained