Synaptonemal complex spreading in plants: Technical aspects and preliminary observations on the synaptonemal complex inPaeonia andOrnithogalum

A modified method for obtaining surface spread synaptonemal complexes (SCs) from pollen mother cells has been developed. Silver-stained SC-preparation of one monocotyledonous species,Ornithogalum flavovirens, and one dicotyledonous plant,Paeonia tenuifolia, were analysed by light and electron microscopy. The SCs in both species frequently broke into roughly equally sized SC pieces with staggered or blunt breakpoints. The telomeric ends of the SCs normally were lacking attachment organelles and, therefore, were hardly distinguishable from blunt breakpoints. Interstitially, shorter stretches of SCs often exhibited unpaired lateral elements. This phenomenon is discussed with regard to segmental incomplete homology and as it relates to the normal sequence of SC morphological changes during the course of meiotic prophase.