polar nucleus fusion
The merging of the polar nuclei, the two nuclei contained within the same cell that are created from the mitotic division of the megaspore during angiosperm reproduction. Polar nuclear fusion takes place in the ovule, forming in the fusion nucleus and giving rise to the endosperm when fertilized.
GO:0000741
karyogamy
is_a
GO:0009559
embryo sac central cell differentiation
part_of