Development of Plant Expression Vector with Taq DNA Polymerase Gene to Yield Heat-tolerant Maize Lines

摘要

Thermus aquaticus (Taq) DNA polymerase has been extensively used in DNA amplification procedures, However, the application of Taq DNA polymerase gene in plant has not yet been reported. In this study, we have focused on using Taq DNA polymerase gene to develop heat-tolerant maize transgenic lines, which would aid in controlling crop loss due to heat stress and potentially increase the economic value. Firstly, an expression vector with Taq DNA polymerase gene was constructed and introduced into the maize ZhongKai inbred lines, Zhong sweet No. 1 and Zhong glutinous No. 2 by pollen-mediated transformation to obtain the transgenic maize plants. Then, the harvested T1 generation seeds were confirmed to be positive transformants by PCR and Southern blotting. The screening of the T2 generation by exposure to heat stress conditions in the field combined with physiological indexes resulted in nine heat-tolerant transgenic maize lines. The expression vector with Taq DNA polymerase gene, developed in the present study, will certainly expand more avenues for heat-tolerant genetic transformation in plants.