Immature male reproductive organs, spikelets and anthers, of four maize gen
otypes were cultured under different conditions. Microsporogenesis and poll
en maturation were observed in each sample. The in vitro matured pollen was
capable of germinating in liquid medium as well as on receptive silks foll
owed by ovule fertilization and seed set. The kernels germinated into norma
l, genetically true plants. Besides the culture conditions the pollen quali
ty was influenced by three major factors: genotype, the size and complexity
of the inoculated sporophytic tissue and the developmental stage of the mi
crospores. Our results will hopefully contribute both to the research into
floral development and to the manipulation of the plant germline.