Composite Endosperm - Variants of Endosperm

In the family Loranthaceae, the development of endosperm is unique. The ovary lacks ovules. The sporogenous tissue located at the base of ovary develops several embryo sacs which elongate considerably, some of them even entering the style. After fertilization, the primary endosperm nucleus of each embryo sac moves to the basal part where it divides to form cellular endosperm. During further development, the endosperms of all the embryo sacs in an ovary enlarge and become fused to produce a composite endosperm mass. Several proembryos belonging to individual embryo sacs with long suspensors develop but only one survives and attains maturity.