Seedless grapes? How do they grow?

Question

I'm curious as to how we have managed to produce a variety of seeldess grape. Surely the seeds are required for the fruit to grow? Any botanists or biologists out there who can explain how it's done?

Answer 1

Excellent Question!!!
Seedless fruits are something of a paradox, as fruits are usually defined in a botanical sense as mature ovaries containing seeds. Among the widely grown seedless fruits are grapes, numerous Citrus fruits (oranges, lemons, limes, etc.), and bananas. Seedless watermelons have only recently been developed -by a Japanese professor Kihara. Seedless fruits are commercially valuable as seeds are considered a nuisance by consumers and seedless fruits are easier to eat and thus preferred over otherwise similar seeded fruits. Most commercially produced seedless fruits have been developed from plants whose fruits normally contain numerous relatively large hard seeds that are distributed throughout the flesh of the fruit; there would be little commercial benefit to a seedless peach or apple. Similarly, fruits with small and unobtrusive seeds, such as strawberries and kiwi fruits, would be little improved by being seedless. And in species whose seed is the commercial or culinary product, such as sesame, most legumes, or grains of all kinds, seedless fruits would be considered a serious flaw.

Seedless fruits can develop in one of two ways: either the fruit develops without any pollination (parthenocarpy), or pollination triggers fruit development but the ovules or embryos abort without producing mature seeds. Seedless fruits are commonly produced on triploid plants, whose three sets of chromosomes prevent meiosis from taking place and thus do not produce fertile gametes. Such plants can arise by spontaneous mutation or by hybridization between diploid and tetraploid individuals of the same or different species.

A common question is how, if they do not produce seeds, such plants can be propagated. In most cases the plants are propagated vegetatively from cuttings, by grafting, or in the case of bananas, from "pups" (offsets). In such cases the resulting plants are genetically identical clones. Oddly enough, seedless watermelons are grown from seeds. These seeds are produced by crossing diploid and tetraploid strains of watermelon, with the resulting seeds producing sterile triploid plants. Fruit development is triggered by pollination and these plants must be grown alongside a diploid strain to provide pollen.

One disadvantage of most seedless crops is that, as genetically identical clones, a pest or disease that can harm one individual can harm every individual of that clone. For example, the vast majority of commercially produced bananas come from a single clone, the 'Cavendish' cultivar, which is currently threatened worldwide by a newly discovered fungal disease to which it is highly susceptible.
Seedlessness is a highly desirable trait in table grape selection, and seedless cultivars now make up the overwhelming majority of table grape plantings. Because grapevines are vegetatively propagated by cuttings, the lack of seeds does not present a problem for reproduction. It is, however, an issue for breeders, who must either use a seeded variety as the female parent or rescue embryos early in development using tissue culture techniques.

There are several sources of the seedlessness trait, and essentially all commercial cultivars get it from one of three sources: 'Thompson Seedless', 'Russian Seedless', and 'Black Monukka'. All are members of Vitis vinifera.

Answer 2

They come from the breeding of grapes that can't produce fertile offspring. It's like when a horse mates with a donkey, you get a mule. An animal that can't reproduce, but as long as horses and donkeys keep going at it, we never run out of mules. So as long as the right grapevines are fertilized by the right other grapevines, we can have seedless grapes.

Answer 3

Spraying of 500 ppm ethral at flowering will produce seedless grapes.

Answer 4

plants reproduce sexually by pollens and ova to produce a fruit with seeds.There is a way called "partheno carpy",it's an artificial way to make those plants produce seedless fruits,they spray the stigmas with pollen extracts or chemicals called auxins and they are stimulated to grow into seedless fruitts.Auxins(plant hormones)also stimulate plants to produce seedless fruits naturally by parthenocarpy llike in bananas or pine apples.

Answer 5

Grafting. Cut a slit on the stem of the plant and tie it again on the main body with a cloth in it's initial position. After sometime,the roots will come out. Now take the stem and bury it in the soil.

Answer 6

we use branch cuttings to propogate seedless fruits (grapes oranges etc)... so that genetically, it is the same set of genes that are being passed on and it is the same bush that is growing anywhere in a world

Answer 7

well the seeds in seedless grapes r so small and soft that when u eat them they feel and taste seedless

Answer 8

they use certain chemicals which prevent the seeds from growing

Answer 9

We use vine cuttings to continue to grow them.

Answer 10

http://science.howstuffworks.com/question349.htm