MEI GENES AND FEMALE MEIOSIS IN MAIZE

The enzyme squash technique on isolation of archeospore cells undergoing meiosis has recently been adapted to maize. The technique allows to study in detail both female meiosis and embryo-sac development. The squash technique is convenient for resolving cytogenetic problems, for example, effect of mei genes impairing different key cytogenetic events of meiosis in micro- and macrosporogenesis. The character of female meiosis in some maize meiotic mutants (am1, am1praI, afd1, dv1) was analysed. The pattern of irregularities of female meiosis in am1, am1praI and afd1 mutants in similar to that in microsporogenesis. The character of female meiosis in dv1 homozygotes is normal and irregularities characterizing male meiosis of divergent genotypes are absent from female meiosis. For the first time, we have the opportunity to vizualise the real cytological effect of mei genes in female meiosis (see Fig. 2-5). Due to the novel squash technique described above, the female meiosis can be possible used as a convenient experimental tool to elucidate some aspects of the great problem of genic control of meiosis and the problems of cell biology.