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In angiosperms, apomixis produces an embryo through asexual reproduction within a seed, bypassing the usual combination of meiosis and fusion of gametes. It can preserve a maternal genetic combination across generations. It differs from vegetative reproduction, which propagates an individual through structures such as shoots or rhizomes rather than through seeds.

Producing a clonal seed requires coordinating more than one developmental event: retaining the maternal chromosome complement and initiating an embryo without ordinary fertilization are separate requirements. Rice research combining altered meiosis with redirected embryogenic gene activity demonstrated clonal propagation through seeds.^[ref] In some forms of apomixis, fertilization is still needed to produce supporting endosperm, so an asexual embryo does not imply that every component of the seed develops without fertilization.

Parthenocarpy is fruit development without fertilization. Because no fertilized ovule is needed to initiate the fruit, it can produce a seedless fruit. It is distinct from apomixis, which produces an embryo or seed without the usual sexual process: a seedless fruit and an asexually formed seed solve different biological problems.

In tomato, increased auxin or gibberellin signalling can trigger parthenocarpy. Experiments with single and combined mutations affecting the two signalling systems separated the growth programme of the ovary from the usual requirement for fertilization. This makes parthenocarpy a useful test of how reproductive development is initiated.^[ref]

Taraxacum is the genus of dandelions, flowering plants whose apparent single flower is a head of many small flowers. Reproduction in the genus includes both sexual systems and apomixis, making species boundaries sensitive to the biological criterion used.

Vegetative reproduction is asexual reproduction through vegetative plant organs, rather than through fusion of gametes. A rhizome can extend below ground and produce a new shoot; a plant cutting can form a root system and become independently established. A piece becoming larger is not sufficient: the process must produce a new potential individual.

The offspring usually preserves the parent's genetic combination because ordinary meiosis and fertilization are bypassed. This makes vegetative reproduction useful for propagating a selected plant, but does not guarantee complete identity indefinitely: mutations can arise during mitosis. Apomixis supplies a useful comparison, because it can preserve a maternal genetic combination through a seed rather than through vegetative plant organs.