HERBICIDE RESISTANT FERTILE TRANSGENIC WHEAT PLANTS OBTAINED BY MICROPROJECTILE BOMBARDMENT OF REGENERABLE EMBRYOGENIC CALLUS

We have obtained fertile transgenic wheat plants resistant to the broad spectrum he bicide Basta(R) (active ingredient phos phinothricin, PPT) by high velocity microprojectile bombardment. The plasmid pBARGUS was used to deliver the selectable bar gene into cells of Type C long-term regenerable embryogenic callus. Phosphinothricin acetyltransferase (PAT) enzyme activity encoded by the bar gene was demonstrated in four independent putative transformed callus lines selected on Basta(R) from two cultivars. Although somatic embryos and shoots were formed in each of the four lines, plants were recovered only from two. More than 100 green R0 plants were regenerated from the first callus line, of which 40 were grown to maturity. PAT activity was shown in each of the 28 R0 plants tested. Southern analyses confirmed the presence of the bar gene in all of the callus fines, and in each of the R0 and two of the four R1 plants tested. Transformed R0, R1 and R2 plants were resistant to topical applications of Basta(R), and the bar gene segregated as a dominant Mendelian trait in R1 and R2 plants.