转Bt基因玉米自交系及其杂交种的抗螟性鉴定

采用基因枪法将Bt基因(GFM CrylA)导入东北春玉米自交系铁7922的幼胚中，获得转基因植株。经过连续3年的田间接卵、室内饲喂玉米螟鉴定，获得稳定抗虫转基因系。以此为亲本与常规自交系配制了四密25Bt、通单24Bt、吉单209Bt3个杂交种。转基因自交系和杂交种的抗螟性鉴定结果表明：转基因系间抗虫性差异极显著，同一转基因系单株间和配制的3个杂交种间抗虫性也存在差异；与对照相比，转基因系配制的杂交种抗虫性明显提高，差异显著。农艺性状鉴定结果显示，转基因系配制的杂交种与对照在株高、穗长、穗行数、行粒数、百粒重上无显著差异。本研究认为，GFM CrylA(Bt)基因可用于玉米的抗螟性改良，也为转Bt基因玉米自交系能够直接用于育种提供了依据。

Identification of Resistance to Corn-Borer of Maize Inbred lines and Hybrids with Bt gene

Bt gene (GFM CrylA) was induced into immature embryos derived from Tie7922, a Chinese northeast spring maize inbred line, by particle bombardment. Transgenic lines with stable resistance to corn-borer were gained by the inoculation of corn-borer eggs in field and the experiment for leaves fed on corn-borer indoor for three succession years. Three hybrids (Simi25Bt, Tongdan24Bt, Jidan209Bt) were created by the hybridization of transgenic lines and common lines, which belonged to improved Simi25, Tongdan24, Jidan209. The results of resistance identification showed that the difference of resistance among transgenic lines was very significant; it had the difference among individuals of the same line and among three hybrids, too. The resistance of hybrids derived from transgenic lines was more than that of common hybrids (CK). The investigation of agronomic characters showed that it had no significant difference between improved hybrids and CK in plant height, ear length, row number per ear, kernel number per row and 100-kernels weight. The paper thought that GFM CrylA (Bt) gene could be applied in the improvement of resistance to corn–borer and maize inbred lines with Bt gene could directly be applied in conventional breeding.