What is Polyembryony and Parthenocarpy?

Difference Between Polyembryony and Parthenocarpy

Polyembryony:

In several genera of angiosperms, more than one viable embryo in the seed has been observed. It is more frequent in Gymnosperms than in angiosperms. This condition arises in various ways:

  • The oospore produces more than one embryo during development as a result of splitting. This is known as cleavage polyembryony and is very common in gymnosperms (e.g. Pinus) and angiosperms e.g. Allium, citrus, and some orchids.
  • An ovule may contain more than one functional megaspore producing as many embryo sacs and oospheres which on fertilization give rise to more than one embryo in the seed.
  • In addition to the normal embryo produced from a fertilized oosphere, the embryo may also be formed from the synergids (e.g. Dandelion) or rarely the antipodals with or without fertilization.

    (iv) Additional embryos may be produced as a result of saprophytic budding by the division of the cells of the nucellus (e.g. lemon) or integument (e.g. onion).

Parthenocarpy:

Parthenocarpy is the development of fruit without fertilization.

As a rule, the development of the ovule into seeds and the enlargement of the ovary into fruit follow only after pollination and fertilization have occurred. In most species of flowering plants, the failure of pollination results in the failure of seed and fruit formation. This usually happens in mature of pollinating insects are not active or the destruction of pollen occurs. In many kinds of fruit trees, if heavy rains fall during the time when pollen is maturing the pollen grains are washed out of the flowers, pollination does not occur and as a consequence few or no flowers set fruits. In some plants, fruits are formed even in the abundance of pollination and fertilization. Such fruits are always seedless. These are succulent and more desirable than normal seed-containing fruits. They are said to be parthenocarpy, while the phenomenon concerned with their formation is termed Parthenocarpy.


There are two main types of parthenocarpy: natural and artificial.

  • Induced parthenocarpy: When seed-less fruits are produced by spraying the stigmas of flowers with ether or water extract of pollen grains or by injecting such growth-promoting substances as in indole acetic acid and naphthalene acetic acid into the ovaries of plants.
  • Natural parthenocarpy: When seedless fruits are produced without any special treatment from the ovaries in the absence of pollination and fertilization. Familiar examples are the naval oranges, grapes, bananas, and pineapples.

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