<p style="text-align: justify;"><b>The Introduced DNA:</b></p>

<p style="text-align: justify;">Since BW7 wheat is a products of mutagenesis and conventional seed increase techniques there was no introduction or incorporation of heterologous DNA into the plant genome. Wheat is an allohexaploid comprising of three complete genomes designated &lsquo;A&rsquo;, &lsquo;B&rsquo; and &lsquo;D&rsquo;. Each genome has an AHAS gene (<i>als3, als2, and als1,</i> respectively), with the mutation giving rise to BW7 located in the <i>als1</i> gene. The tolerance to imidazolinone herbicides is due to a point mutation of a single nucleotide and the amino acid sequence of the mutated enzyme differs by one amino acid from that of the unmodified enzyme. This single change in the amino acid sequence alters the binding site of AHAS to imidazolinone herbicides, such that the herbicide cannot inhibit the enzyme&rsquo;s activity. The mutation of the AHAS gene was identified from information on the gene sequence.</p>

<p style="text-align: justify;"><b>Genetic Stability of the Introduced Trait:</b></p>

<p style="text-align: justify;">Segregation analysis over multiple breeding generations of BW7 was shown to be consistent with the inheritance of a single gene.</p>

<p style="text-align: justify;"><b>Expressed material:</b></p>

<p style="text-align: justify;">The modified AHAS gene, conferring tolerance to imidazolinone herbicides, is under control of the native AHAS promoter and is believed to be constitutively expressed. Whole plant tolerance to this herbicide was expressed in BW7.</p>

<p style="text-align: justify;">In the unmodified plant, the levels of valine, leucine and isoleucine are regulated by feedback inhibition of AHAS. A mutation in the AHAS enzyme could affect the regulation of the biosynthesis of these amino acids. Data were submitted to show that the modified AHAS was feedback inhibited by valine and leucine, similar to the unmodified enzyme. Levels of valine, leucine and isoleucine in BW7 were comparable to those in the unmodified parental lines.</p>
