Pollen vigor and detection of exogenous genes of litter for transgenic triploid Populus tomentosa

ObjectiveLong-term and continuous research on the safety evaluation of transgenic trees is significant to the development of forest tree genetic improvement and the biosafety evaluation of transgenic trees.

MethodIn this study, the pollen vigor and hybrid seed setting rate of transgenic triploid Populus tomentosa with AhDREB1 gene were continuously observed in the field for 11 years and 13 years. In addition, the foreign genes in the transgenic triploid Populus tomentosa were detected under natural conditions, and 44 kanamycin-resistant bacteria were screened from the rhizosphere soil of transgenic triploid P. tomentosa, and the genomic DNA of bacteria was used for PCR detection.

ResultThe results of MTT and TTC staining showed that the transgenic triploid Populus tomentosa pollen had no vigor. The results of hybridization test again showed that the transgenic triploid Populus tomentosa pollen may not have the cultability and fertility, and the hybrid seed setting rate was zero. The litter (branches, stems and leaves) of the transgenic poplars was buried in the soil, falling on the surface and falling on the lawn, and the foreign genes were not detected after 3 months. The exogenous gene in the 13-year-old transgenic triploid Populus tomentosa litter had not been transferred horizontally to the rhizosphere soil culturable bacterial genome.

ConclusionThis study did not find that the transgenic triploid P. tomentosa, which was grown in the field for 13 years, had a significant impact on the surrounding ecological environment.