Research On Identification Technology About The Insect-Resistant Trait Of Bt Transgenic Progeny In Maize

The insect-resistance trait of F2,F3,F4 progeny from transgenic Bt hybrids NC7882 and transgenic Bt inbred lines C237 were identificated by five differ- -ent methods as kanamycin identification, hygtomycin iden tific at ion, identification of insect -resistance in field and PCR analysis. PCR primers were designed according to sequence of Bt gene and NOS terminator,The amplify- -ing results by two pairs of primers PCR revealed that the length of amplified flagment was consistant with the length expected. This indicated that the Bt gene and NOS terminator were existed in the progeny of NC7882 and C237. T-test of pairs data showed there was no obvious difference between the result of insect -resistance identification in field and that of W primer PCR identifica- -tion,which was regarded as standard identification technique . There was obv- -ious difference between the result of NOS primer PCR identification and that of W primer PCR identification,So the result of NOS primer PCR identificati- -on was truthless.Because NOS primer PCR anplified flagment was not enough long,it was not easy to distinguish the amplified flagment from small DNA piece by gelose electrophoresis . There was significant difference between the results of kanamycin identification and that of W primer PCR identification, but there was no significant difference between identifying result of hygtomycin with 500mg/L concentration and that of W primer PCR.This indicated that the anti-- hygtomycin gene was existed and express, anti-kana- -mycin gene was not existed or not express in transgenic Bt hybrids NC7882 and transgenic Bt inbred lines C237. Thus the method about hygtomycin涂抹(daub) leaf can indirectly identify Bt gene . In NC7882 and C237 progeny the segregation of Bt+and Bt-plants fitted 3:1 in NC7882F2and parts of F3, F4 linesally ,which showed one pair dominant gene Mendel inheritance.Those researchs about identification methods and selection insect-resistance lines in Bt transgenic Progeny make a solid base for insect-resistance.breeding.