Seedless

A seedless fruit is a fruit developed to possess no mature seeds. As consumption of seedless fruits is generally easier and more convenient, they are considered commercially valuable.

Most commercially produced seedless fruits have been developed from plants whose fruits normally contain numerous relatively large hard seeds distributed throughout the flesh of the fruit.

Common varieties of seedless fruits include watermelons, tomatoes,grapes (such as Termarina rossa), and bananas. Additionally, there are numerous seedless citrus fruits, such as oranges, lemons and limes.

The term "seedless fruit" is biologically somewhat contradictory, since fruits are usually defined botanically as mature ovaries containing seeds.

Seedless fruits can develop in one of two ways: either the fruit develops without fertilization (parthenocarpy), or pollination triggers fruit development, but the ovules or embryos abort without producing mature seeds (stenospermocarpy). Seedless banana and watermelon fruits are produced on triploid plants, whose three sets of chromosomes make it very unlikely for meiosis to produce fertile gametes. This is because one of the three copies of each chromosome can't pair with another appropriate chromosome before separating into daughter cells, so these extra third copies end up randomly distributed between the two daughter cells from meiosis 1, resulting in the (usually) swiftly lethal aneuploidy condition. Such plants can arise by spontaneous mutation or by hybridization between diploid and tetraploid individuals of the same or different species. Some species, such as tomato,pineapple, and cucumber, produce seedless fruit if not pollinated, but will produce seeded fruit if pollination occurs.

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