nonendospermic

Nonendospermic refers to seeds in which the endosperm tissue is absent in the mature seed. In most angiosperms, the endosperm forms as a nutritive tissue during fertilization, but in nonendospermic seeds the endosperm is reduced, absorbed, or never formed. As a result, the nutritive reserve is stored mainly in the embryo’s cotyledons, which may be rich in starch, oil, and protein. In some species, nutritive tissue may instead be supplied by perisperm, a tissue derived from nucellus, rather than true endosperm.

Nonendospermic seeds are also described as exalbuminous, in contrast to albuminous seeds that retain endosperm at maturity. This condition is common among many dicot families, particularly the Fabaceae (legumes). In these seeds, the embryo develops with prominent cotyledons that remain enclosed within the seed coat after maturation, and the seed germinates by mobilizing reserves from the cotyledons rather than from residual endosperm.

Examples of nonendospermic seeds include peas, beans, lentils, and chickpeas, which store most of their energy in the fleshy cotyledons. The absence of a persistent endosperm influences seed size, shape, and germination behavior, and it is a characteristic feature used in anatomical and taxonomic descriptions.

In summary, nonendospermic seeds lack mature endosperm, relying on cotyledons (and occasionally perisperm) to store nutritive reserves, a pattern especially prevalent among legumes and other dicot groups.