REPRODUCTIVE-BEHAVIOR IN MAIZE-TRIPSACUM POLYHAPLOID PLANTS - IMPLICATIONS FOR THE TRANSFER OF APOMIXIS INTO MAIZE

Expression of gametophytic apomixis in grasses is restricted to polypl oid plants. In our effort to transfer apomixis from diplosporous tetra ploid Tripsacum (2n = 4x = 72) into maize (2n = 20) through convention al backcrosses, we produced polyhaploid plants combining one complete set of chromosomes from each genus, These polyhaploid plants were tota lly male sterile, By contrast, viable seeds were produced apomicticall y when they were pollinated using maize, Apomictic reproduction in suc h polyhaploids, which show a diploid-like chromosomal complement, sugg ests that diplosporous apomixis and polyploidy are not totally linked and that diploid crops such as maize might reproduce apomictically.