Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School


First Advisor

Gerald A. Myers


Several questions were posed at this point which led to the hypotheses to be tested in this investigation. The experimental design was divided into 3 phases. For a detailed description of the design, see Appendix A. Phase I of this study involved a comparative study of the anatomy of the apices of plants of Eucharis grandflora, the Amazon lily, exposed to heat (27-29° C) for one, two, three, four or five weeks, in an effort to see if manifestations of floral evocation and/or initiation are in evidence when compared to the control. Since the time from the end of heat to flower was essentially the same at all temperatures (Adams and Urdahl, 1971), a difference in the velocity of evocation (and/or initiation) must occur. Another problem to be addressed in this phase of the study will be whether differences in the velocity of apical change is the same whether heated for one, two, three, four or five weeks. If there is no apparent changes taking place, then how long after heating has stopped must one wait before visible changes in the apical meristem will occur? Phase II will be concerned with floral morphogenesis of three-week heated plants. The question to be answered here will be: What was the developmental sequence of the thermoinduced apex through the life cycle when bulbs are heated for three weeks at 29° C and then returned to 18° C? Phase II will also compare developmental stages of two-, three- and five-week heated plants. Phase III will correlate Phase II development with the development of the first lateral, which will become the next floral axis (the next bulb). This will be collected through the twenty-third week (160 days) or up until the bulb is ready to start the next reproductive cycle. These questions present themselves for consideration. In the developmental sequence of the new terminal growing point: When is the new apex visible? When does it begin to function? When does it initiate new leaf primordia? What is the developmental condition six weeks after the last flower has died on the scape? Is it structurally ready to be induced to flower?

Library of Congress Subject Headings

Plants, Flowering of




South Dakota State University

Included in

Biology Commons