Contributions to the cytology of endosperm in some angiosperms

Cytological observations on the endosperm ofZephyranthes grandiflora have shown that the endosperm is triploid in general, with 3n=36 chromosomes, but that nuclei of higher polyploidy also occur. Wall formation started at 7 days after pollination and the 9 day old endosperm was completely cellular. Maximum variation in size and shape of nuclei was recorded in the 8 day old endosperm. No, similar variation was observed in the root tip nuclei. Polyploidy by endomitosis, and probably also by fusion of nuclei, together with aneuploidy may be responsible for the nuclear variation in the endosperm. The low seed setting has been attributed to the failure of endosperm resulting from the mitotic irregularities which characterized the collapsing endosperm.