The appearance of amyloplasts as one of the features distinguishing the initial stages of the development of isolated endosperm in kiwiberry

Abstract

The potency of plant cells’ reaction to dedifferentiation and then proliferation corresponds with cell reorganization. The details of cell modifications may rely on the fate of the cells. In this study, the characteristics of an endosperm and specific storage tissue under organogenic and non-organogenic development pathways were analyzed. The experimental system was based on isolated endosperm explants (with the seed coat and embryo removed) of kiwiberry cv. Bingo, placed on organogenic (OCIM) and non-organogenic (NOCIM) callus induction media that differed in the type and concentration of plant growth regulators. Histological and ultrastructural analyses of freshly isolated endosperm and explants afer selected periods of the culture were performed using stereoscopic, bright field, and transmission electron microscopy techniques. The dedifferentiation for both pathways– organogenic and non-organogenic – was similar at the morphological level for the first week of the culture. The histological and ultrastructural analyses revealed limited amyloplasts in the cells on OCIM. e organization of proliferated tissue differed significantly from two weeks of the culture: it was more compact for OCIM and looser for NOCIM. Additionally, at this period, there were more amyloplasts with starch granules in dedifferentiated cells on OCIM. The limited starch granules in proliferated cells on NOCIM were observed only afer four weeks of the culture. The presence of plastids with starch granules depends on the competence of endosperm-derived callus in kiwiberry to organogenic processes and can be an early marker of callus destination.