Abstract
Anatomy of the achene is studied in four varieties of Cannabis sativa (sativa, spontanea, indica, and kafiristanica) at different stages of its development from the ovary. The nucellus undergoes extensive curvature soon after fertilization so that the campylotropous ovule assumes an ana-amphitropous form. The endosperm is nuclear and shows a permanently coenocytic haustorial caecum. The embryo, when mature, is curved and dicotyledonous and occupies most of the space in the seed. The cotyledons enclose a set of well formed plumular leaves. Stored food is present in cells of both the radicle and the cotyledons and also in one to several layers (depending on position) of the endosperm. The seed coat has little or no protective role in the propagule but chloroplasts are formed in it soon after the globular embryo stage. In the pericarp, it is the endocarp layer that undergoes the most striking transformation; the cells show gross enlargement and extensive cell wall modification and thickening. The layer which lies immediately above the endocarp as well as the epicarp also show wall thickening but no significant increase in cell size. A careful comparison at identical stages among the four varieties reveals no significant difference is achene development.
Published Version
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