Study On Environmental Behavior Of Expression Product Of Exogenous Bt Gene In Transgenic Plant

In this paper, poplar 741, Populus tomentosa, Pb29 (transgenic poplar 741 with BtcrylAc gene) and CC71 (transgenic poplar 741 with Btcry3A gene) were used as the materials, mRNA transport law of exogenous Bt gene, transport mechanisms and rules of exogenous Bt toxin protein and insect-resistance of transgenic poplar 741 grafted were studied by using the grafting procedure; to poplar 741, Populus tomentosa, Pb29 (transgenic poplar 741 with BtcrylAc gene), transgenic cotton Guoshen GK45 (transgenic BtcrylAc gene) and non-transgenic cotton Handan109 for the material, the establishment of four kinds of Poplar-cotton composite system, the law of concentration, distribution and degradation of exogenous Bt toxin protein was studied.1 In order to discover whether mRNA of BtcrylAc gene was transported between the stock and scion, a study was made by means of RT-PCR technology while poplar741 and Pb29 were grafted as scion and stock mutually. The result of RT-PCR test was that mRNA of BtcrylAc gene was not detected in the branch and leaf of poplar741 as scion or stock; therefore it meant that mRNA of BtcrylAc gene was not transported between the stock and scion.2 In order to discover whether mRNA of Btcry3'A gene was transported between the stock and scion, a study was made by means of RT-PCR technology while poplar741 and CC71 were grafted as scion and stock mutually, and Pb29 was grafted onto CC71 rootstock. The result of RT-PCR test was that mRNA of Btcry3Agene was not detected in the branch and leaf of poplar741 and Pb29 as scion or stock; therefore, it meant that mRNA of Btcry3A gene was not transported between the stock and scion.3 While poplar741 and Pb29 were grafted as scion and stock mutually, Populus tomentosa and Pb29 were grafted as scion and stock mutually, CC71 and Pb29 were grafted as scion and stock mutually and poplar741 were grafted Pb29 as intermediate stock, in order to study on transport mechanisms and rules of exogenous BtCryl Ac toxin protein by means of ELS A technology. The results of ELISA test were as follows:BtCryl Ac toxin protein was all detected in the leaf, phloem, xylem and pith of poplar741 and Populus tomentosa as scion or stock; BtCry1 Ac toxin protein was only detected in the leaf, phloem of CC71 as scion or stock, but BtCry1 Ac toxin protein of xylem and pith were not detected. Therefore, it demonstrated that BtCry1 Ac toxin protein was transported between the stock and scion by means of grafting and phloem was mainly transport. but two kinds of exogenous proteins (BtCry1Ac and BtCry3A) antagonized during transport.4 While poplar741 and CC71 were grafted as scion and stock mutually, Populus tomentosa and CC71 were grafted as scion and stock mutually, Pb29 and CC71were grafted as scion and stock mutually and poplar741 were grafted CC71 as intermediate stock, in order to study on transport mechanisms and rules of exogenous BtCry3A toxin protein by means of ELISA technology. The results of ELISA test were as follows BtCry3A toxin protein was all detected in the leaf, phloem, xylem and pith of poplar741, Populus tomentosa and Pb29 as scion or stock, but BtCry3A toxin protein content of xylem and pith were lower. therefore, it demonstrated that BtCry3A toxin protein was transported between the stock and scion by means of grafting and xylem were mainly transport. But two kinds of exogenous proteins (BtCry1Ac and BtCry3A) antagonized during transport.5 With the aim of finding out the influence of grafting poplar741 with transgenic BtcrylAc gene on Clostera anachoreta Fabricius and Hyphantria cunea (Drury), the larvae of C. anachoreta and H. cunea were fed indoors on the leaves of scion which had been grafted. The results showed that grafting poplar741 with transgenic BtcrylAc gene had some toxin effects on the younger larvae of C. anachoreta and H. cunea and inhibited of growth and development of the older ones, could extend the larval developmental period of C. anachoreta and H. cunea, lower rates of larval body length and weight, reduced frass quantity and eating leaf area of the larvae, resulted in poor larval growth and development, and even express certain resistance to insects.6 With the aim of finding out the influence of grafting poplar741 with transgenic Btcry3A gene on Plagiodera versicolora (Laicharting), the larvae of P. versicolora were fed indoors on the leaves of scion which had been grafted. The results showed that grafting poplar741 with transgenic Btcry3A gene had some toxin effects on the younger larvae of P. versicolora and inhibited of growth and development. It could extend the larval developmental period of P. versicolora, lower rates of larval body length, reduced pupa weight of the older ones, and even express certain resistance to insects.7 It was studied that the expression of exogenous BtCry1Ac gene of transgenic poplar Pb29 and transgenic cotton Guoshen GK45 in poplar-cotton composite system by means of ELSA technology. The results showed that the contents of exogenous BtCry1Ac toxin protein branch leaves, short branch leaves and root firstly increased and then decreased in the growth and development of transgenic poplar Pb29. The contents of exogenous BtCry1Ac toxin protein branch leaves were higher than that of long branch leaves. On 20 June the contents of exogenous BtCrylAc toxin protein were less that of long branch leaves and short branch leaves and higher than that of long branch leaves and short branch leaves later. The contents of exogenous BtCrylAc toxin protein, stems and leaves decreased along with the growth of transgenic Guoshen GK45. The contents of exogenous BtCrylAc toxin protein of stems decreased more slowly and always maintained a high level, while that of roots and leaves decreased rapidly and reached a minimum level to the late plant growth and development, were less than that of stems.8 It was tested whether soil were the presence of BtCrylAc toxin protein in poplar-cotton composite system or not by means of ELSA technology. The results showed that a few sampling points had the presence of BtCrylAc toxin protein, but the concentrations were very low in the rhizosphere soil of transgenic poplar Pb29 and transgenic cotton Guoshen GK45, topsoil of non-transgenic poplar and transgenic cotton composite system (B, D), topsoil of transgenic poplar and transgenic cotton composite system (E, G), topsoil of transgenic poplar and non-transgenic cotton composite system (F, H).