Popular Science Monthly/Volume 79/October 1911/Perfect Flowers in Maize
|PERFECT FLOWERS IN MAIZE|
UNIVERSITY OF NEBRASKA
IN The Popular Science Monthly of January, 1906, the author wrote a brief article entitled, "What is an Ear of Corn," presenting some observations on the occurrence of hermaphrodite flowers in maize; this occurrence with other evidence indicating that maize had probably originated in some manner from a perfect flowered plant, while in all cultivated maize the flowers are strictly single, being either male or Fig. 1. Hermaphrodite Flower of Maize (Zea mays) showing structural features (reproduced from former article). female. However, a comparative study of male flowers (from the tassel) and female flowers (from the ear) showed analogous parts in both. The tassel flowers in the older stages, however, are borne in pairs, while the ear flowers are single, but a study of the embryonic ears showed the male flowers to be twinned at this stage, but as development took place one of these flowers became entirely abortive and only one fully developed. Perfect flowers were also found in somewhat deformed plants, which looked in many ways like reversion in types. A study of the gross structure of the ear and tassel showed a close structural analogy between the ear (including cob)
and the central spike of the tassel, and strong evidence was found in support of the theory that the ear was a development from the central spike of the tassel borne on a lateral branch of the plant, the other branches of this tassel becoming abortive. Good examples were found of ears, showing remnants of these lateral tassel branches, confirming the above statements. At that time the author had only observed the perfect flowers in the very young stages of development and on more or less deformed plants. Fig. 1 is reproduced from the article referred to, indicating the character of these flowers.Since then, types of corn showing this hermaphrodite flower on normal types of ears have been observed. Fig. 2 is an illustration of such an ear. Some thirty plants of this were grown and all came true
to type. The ear was about six to eight inches in length and of normal appearance, except that each seed had three fully developed stamens, arising from near the base. The plant, however, was very peculiar in appearance, as shown in Fig. 3. The plants were about five feet in height, the stem short jointed, with broad leathery leaves, resembling tobacco plants as much as corn plants. Professor Emerson, of this station, has had hermaphrodite plants occur in several of his corn hybrids and in all cases they have had this peculiar type of foliage. If this type should be a reversion toward the primitive type it would be of great interest, since we have no grass plant at present having this appearance.
Another most interesting ear of perfect flowers was found by chance in a lot of Boone County White Corn, secured from a prominent grower. This variety represents the highest development in modern improved corn. The ear in question was unusually large and well developed, as shown by Fig. 4, the ear weighing about 16 ounces. Fig. 5 is a cross-section of the same, showing the presence of stamens with every kernel. Fig. 6 is an enlarged photograph showing both sides of one kernel. On the anterior side are shown three well-developed stamens. On the posterior side, at the very tip and practically embedded in the cob, are three small stamens. These are the last remnants
Fig. 6. Showing both sides of Kernel, from Ear in Fig. 4. Three well-developed stamens shown on posterior side. On the anterior side and embedded in the cob were three rudimentary stamens, remnants of the abortive flower.
of the abortive flower, described in the former article referred to. This little abortive flower can only be found in the early embryonic stages of development, and usually all trace of its presence is lost except the extra pair of glumes on the posterior side of the kernel. These little stamens, however, indicate that at one time it might have functioned and give us another clue to some of the evolutionary changes that this interesting plant may have gone through.
- The seed of this was secured from Mr. C. P. Hartley, Department of Agriculture, Washington, D. C, who discovered the plant as a reversion in one of his breeding plats.