ABSTRACT

Maize or corn (Zea mays (L.)) is an annual, and ranks third behind wheat and rice in total crop hectarage grown in the world. Maize is typically a monoecious plant having a panicle male inflorescence arising from the stem apex, and highly compacted spike female inflorescences originating from upper main stem branch apices. Excellent pictures of the very early development of unisexual male and female flowers of Zea mays from bisexual initials in both tassels and ears have been published recently. Tassel sterility is the inability of a tassel flower to produce and dehisce viable pollen, and sex reversal is the production of pistillate flowers on the tassel. Male sterility and sex reversal commonly occur through genetic means in maize. Ear differentiation initially appears very similar to tassel differentiation in that the vegetative apex of an axillary bud elongates slightly to form the transition stage a few days before it differentiates.