Transferring Maize Transposable Elements to Bread Wheat through Wheat x Maize Crossing

Transposon tagging and insertional mutagenesis are important reverse genetic tools in eukaryotes. These are widely used for understanding gene function and targeted manipulation of genes in crop improvement. The maize transposon based insertional mutagenesis  has proven to be very successful for gene tagging not only in maize but also in other plant species including tobacco, Arabidopsis, peas, rice, and barley.  The major food crop wheat however, does not have any efficient transposon tagging or insertional mutagenesis system. Here we show an efficient, easy to adopt, high frequency insertional mutagenesis system in bread wheat using well characterized maize transposable elements. We optimized the wheat x maize doubled haploid (DH) system to introduce the maize Mutator family transposable elements (TE’s) into wheat genome with a success rate of 10 % for the screened transposable elements. DNA gel blot analysis showed some of these elements were stably transferred to their progenies. Various phenotypic differences were observed within the progeny of selected DH plants. Autonomous transposon Mu9 that encodes MuDR A and MuDR B proteins was also transferred to wheat genome. Our study demonstrates the possibility of saturating wheat genome with transposon insertions without using genetic transformation. The most current status of the project will be presented at the meeting.