This type of reproduction in plants is centered around the flower's ovum

and pollen fusing together:

sexual reproduction

Explanation:

The type of reproduction in which the ovum and the pollen of a flower fuse together is refer to as sexual reproduction.

The ovum of a flower is equivalent to the female reproductive part while the pollen is equivalent to the male's reproductive part. During fertilization, the female reproductive part (the ovum) fuses with the male's reproductive part (the pollen) to produce a zygote.