13. Floral histogenesis in maize.

For a number of years work has been done on the developmental morphology of the maize ear and tassel. Early studies were published in the Journal of Agricultural Research 60:25‑38. 1940, and in the Annals of the Missouri Botanical Garden 35:269‑287. 1948. These papers dealt with the visible external changes in the shoots of the maize plant during the differentiation and development of the tassel and ear.

During the past two years work has been done on the histology of different stages in the development of the tassel and ear. Five ear types, four‑row, flint (eight‑row), 16‑rowed types, fasciated (20 or more rows), and ramosa are being used. These histological studies trace the changes from the vegetative to the floral shoot and the beginning of the various plant and flower parts in the different zones of the shoots that give rise to them. The purpose of these studies is to see when, where, and in what order the flowers and flower parts originate. These studies will probably be published in a Station bulletin in the near future.

O. T. Bonnett