Polyembryony in maize: histological analysis

Abstract

The histological analysis enabled to distinguish the main types of polyembryony in maize according to the origin of embryos connected with their localization in caryopses, differences in their structure (presence of common tissues) and type of germination. Twin embryos from multiple embryo sacs are usually localized on opposite sides (or distant places) of the caryopsis, they have no common tissues and the germination is separate. Twins or triplets from individual cells of the egg apparatus or multiple egg cells are closely adherent, but strictly separated by epidermal layers. Endosperm is common. Plumules and radicles are independent. Cleavage polyembryos arising in vivo spontaneously or after induction share a common suspensor, part of scutellum and surface layers of radicles. Therefore they germinate with one radicular complex and with separated plumules.