Parthenocarpy
This is the production of a fruit without a seed, the term ‘parthenocarpy’ deriving from the Greek for ‘virgin fruit’.
The ‘normal’ development of a fruit occurs when pollen reaches the female parts of the plant and gibberellin hormones within the pollen trigger the production of another hormone, auxin, which in turn causes the fruit to develop. Parthenocarpy in plants occurs when auxin levels in the ovary are naturally high, or have been artificially increased, and pollination has not occurred. This may lead to a fruit being produced without a seed (ie without an embryo).
This is a useful phenomenon for the commercial production of crops such as cucumbers, bananas and pears where consumers generally prefer them to be seedless.
The production of seedless grapes generally uses a similar process called ’stenospermocarpy’. This allows pollination and fertilisation to take place as normal but the seed (the embryo) is aborted very early on. The fruit continues to develop but is virtually seedless.