Scanning Electron Microscope Studies of Apices of Lilium longiflorum for Determining Floral Initiation and Differentiation1,2

Abstract

Intact stem apices of Lilium longiflorum Thunb. cv. ‘Ace’ were prepared for scanning electron microscopy to determine floral initiation and differentiation by viewing topographical changes. The apices, after removal of leaves under running water, were frozen in liquid N2, freeze-dried on carbon discs and coated with carbon prior to viewing. Electron photomicrographs were taken of vegetative, transitional and reproductive apices. This method of tissue preparation permitted microscopic evidence of flower bud initiation and differentiation to be obtained in less than 9 hr after removal of the apex from the plant. The apices retained their in vivo configuration, but as dry, permanent, 3-dimensional mounts. Cell net studies of the apical meristem are possible with this technique. This method of preparation is also adaptable to light microscopy.

Scanning Electron Microscope Studies of the Shoot Apex in Dianthus caryophyllus L. cv. Scania1

“…The dome and leaf primordia show large areas of desiccation due to the electron beam and the vacuum. The dessication shown by Einert et al (5) was due to sample preparation artifacts.…”

“…Sattler (12) described a technique for the study of floral development by viewing whole fixed and stained shoot apices in 100% ethanol with an incident light condenser and objectives with dipping cones. Einert et al (5) recently described a method of determining floral initiation and differentiation of the shoot apices of Lilium longiflorum Thunb., using the scanning electron microscope (SEM). Results presented by Einert et al (5) on Lilium and Heslop-Harrison (8) with Elodea show promise for such a technique.…”

“…Einert et al (5) recently described a method of determining floral initiation and differentiation of the shoot apices of Lilium longiflorum Thunb., using the scanning electron microscope (SEM). Results presented by Einert et al (5) on Lilium and Heslop-Harrison (8) with Elodea show promise for such a technique. The SEM is useful in studying microtopographical features because of the depth of field, magnification, and resolution.…”

Electron Optics: Principles, Techniques, and Applications in Horticulture1

“…The organogenesis of meristems by SEM analysis gives a total picture of meristimatic activity and morphology (36). The lily (32) and carnation (33) developmental stages have been clearly identified and characterized. Mutational alteration of the reproductive apex in carnation (33) has led to a better understanding of the sequence of events in carnation flower production.…”