TRANSGENIC PLANTS OF LOLIUM-MULTIFLORUM, LOLIUM-PERENNE, FESTUCA-ARUNDINACEA AND AGROSTIS-STOLONIFERA BY SILICON-CARBIDE FIBER-MEDIATED TRANSFORMATION OF CELL-SUSPENSION CULTURES

Seven Lolium multiflorum, one Lolium perenne, 12 Festuca arundinacea a nd six Agrostis stolonifera plants were regenerated following transfor mation with a hygromycin resistance gene and hygromycin selection, fro m cell suspension colonies treated with silicon-carbide whiskers. Tran sformation was confirmed by PCR and Southern blotting; the latter also showed that six of the L. multiflorum plants were independent transfo rmants (insufficient molecular evidence was obtained for the seventh), nine of the 12 F. arundinacea plants were independent transformants, but that all the A. stolonifera plants were derived from a single tran sformation event. Most plants tested contained fewer than five integra ted transgene copies. Transgene expression was confirmed by reverse tr anscriptase-PCR (RT-PCR). Of the one A. stolonifera and three L. multi florum transformants regenerated after co-transformation with both the hygromycin resistance gene and the beta-glucuronidase (gusA) gene, no ne were found to express GUS activity. L. multiflorum regenerants from older (14-16 week old) cell suspensions showed loss of female fertili ty, but analysis of the progeny from three plants showed that the tran sgenes were being inherited as a single dominant allele with a high fr equency of transmission of hygromycin resistance. (C) 1998 Elsevier Sc ience Ireland Ltd. All rights reserved.