Study On Genetic Transformation Of Hevea Brasiliensis

Hevea brasiliensis is one of the important economical trees. For its characteristics of long producing-latex time and laticifer system, it may be developed for the high-efficient and low-cost bioreactors, which has the large potential for commercial exploitation. Establishment of stable and high-efficiency genetic transformation system is the key step to develop the rubber tree into the bioreactor.Employing the anthers of Hevea Brasiliensis Haiken 2 , Reyan88-13, Reyan7-33-97 as explants, we investigated some factors involved in induction of callus and genetic transformation, and attempted to improve the efficiency of genetic transformation by employing the embryogenesis-related genes. The preliminary results are as follows.(1) Employing the anthers of Hevea Brasiliensis Haiken 2, Reyan88-13, Reyan7-33-97 as explants to induce the callus, the optimal temperature is 26°C in the daytime and 25 °C in the nighttime, and the concentration of ABA is 0.25mg/L in media.(2) According to brown degree of callus infected by Agrobacterium tumefaciens, the callus, about 25 days after inoculatation , was selected as explants for transformation and concentration of superpure sugrose was 3g/L in medium. We also found that the anther callus is insensitive to Kan and Kan was not suitable for screening the H.brasiliensis callus transformats.(3) PEI1, the gene encoding embryogenesis-related gene, was cloned by polymerase chain reaction from Arabidopsis and the plant expression vector pBIP with 35S::PEI1 was constructed.. The plant expression vectors, pBIP with 35S::PEIK pBIN with UBI::BnBBMl and pBI121, were respectively introduced into Agrobacterium tumefaciens strain LBA4404 and EHA105.(4) Some transformatied plants were obtained by Kan-resistance screening. A UBI::BnBBMl transgenic plant was respectively confirmed by histochemistry and PCR analysis. We could not get the 35S::PEI1 transgenic plants. The results implied that the efficiency of H.brasiliensis genetic transformation could not be obviously influenced by BnBBMl and PEIl genes.