Eli5 How do people grow seedless watermelons? Like where do they get the seeds?


Eli5 How do people grow seedless watermelons? Like where do they get the seeds?

In: Other

They still come from seeds. It is sterile tho, it can grow but won’t reproduce. It is like using the seeds for one time only.

Many seedless plants like Bananas are grown from cuttings, making all commercial banana plants genetic clones of each other.

But seedless watermelons are in fact grown from seeds. Diploid and Tetraploid watermelon varieties are cross pollinated to produce a sterile (seedless) watermelon plant.

>How do people grow seedless watermelons?

They plant seeds for seedless watermelons and they grow. 😋

>Like where do they get the seeds?

Farmers buy those seeds from seed manufacturers (like Monsanto or DuPont).

If you are asking how are seedless watermelon seeds created, then that has to do with the cross-breeding of two specific strains of watermelon — *one diploid (normal complement of DNA) with one tetraploid (double the normal amount of DNA)* — which results in a sterile strain. So seedless watermelons are sterile, meaning that they can produce no offspring, so the seeds present (they are not truly seedless) are very slight and are hardly noticed when eaten.


1. Poke a hole in the ground
2. Cover it with dirt
3. Water and wait a few weeks
4. Boom, seedless watermelons

They treat regular seeds with a chemical called colchicine that messes up their genetic makeup, making them unable to produce seeds.

Source: I studied this in chemistry class

To make a baby, mom and dad make special cells that combine to make a baby. These special cells are called “germ cells”. Each germ cell has half of special instructions to make the cells that will make up a new person, and you need both halves of the instructions, one from the mom and one from the dad, in order to make a new person.

Almost all cells in your body will have an entire set of its special instructions to make it work, and when the cell divide to make new cells, they will make another full copy of these instructions.

These special instructions are written on a tiny books called “chromosomes”. Because these special instructions are so important, we have two copies of each book, or chromosome, so that if one of the books gets smudged or copied wrong, our cells can rely on the other book to figure out what to do.

But remember, the germ cell is special because it only has half of the special instructions. Luckily for us, figuring out which half of the special instructions to put into a germ cell is much easier because we have two copies of each chromosome: we put one copy of each book into each germ cell instead of both copies.

To do this, the chromosomes do a little dance while a cell divides. The chromosomes find their partner and then line up. One partner gets pulled to opposite sides of the cell, and the cell splits in half into germ cells. This process of making a germ cell with only a single copy of each chromosome is called “meiosis”.

Some plants are like people too. They need to have a germ cell from a mom and a dad in order to make new baby plants. Seeds that grow into plants are cells that have already have combined the instructions from a mom and dad germ cell.

Watermelons are a special type of plant that can either have two copies or four copies of the chromosomes, the books that half all the special instructions. When you have seeds that have four copies of chromosomes, they undergo meiosis normally, and the germ cells have two copy of the chromosomes.

**Seedless watermelons come from seeds that were made from combining a parent with two copies of chromosomes with four copies of chromosomes.** From one parent, the seedless watermelon will inherit one set of chromosomes, and from the other parent, it will inherit two sets of chromosomes. **That means that it will have three sets of chromosomes in most of its cells.**

A seedless watermelon can grow up looking normal, but it has a bit of trouble when it comes to making germ cells of its through meiosis.

Remember that the cells do a special dance to find its partner? **Well, when you have three copies of each chromosome**, they have a lot of trouble finding a dance partner, and so **the process of creating germ cells become a lot more difficult.**

That’s why in seedless watermelons don’t have seeds, because they can’t make the germ cells that would end up becoming seeds.

TL;DR: Seedless watermelons are seedless because it was born with three sets of each book and their books can’t find dance partners. But its parents could make seeds because they had two or four sets of each book.

Some men can’t make sperm. It’s the same thing. They found a watermelon that’s shooting blanks, then they got that watermelon’s parents to make more babies.

A mule is a crossbreed from a donkey and horse. It’s sterile.

You can crossbreed plants too. Take pistil from one and put it in the flower of the 2nd (or just have them close and trust bees). 2 specific species of watermelon make seedless watermelon when mixed. It’s sterile.

So imagine you have a European outlet and an American outlet. Both outlets work wonderfully with their respective pieces. This is how watermelon reproduction is for simplicities sake. You have American watermelon and European ones. Now if you mix them up it still makes a watermelon. But this new watermelon has a European outlet and an American plug. This means you can eat the watermelon but it can’t conduct electricity. Thus there are no seeds. The two types of watermelons are called diploid and tetroid. When breeded together they make a water melon, but it can’t make seeds cause the outlet doesn’t connect.

I’m sorry to not answer your question, but it’s in line with it. Did you know that every apple of the same variety comes from a single parent tree? Every apple seed contained in an apple will grow a tree with different properties, so the branches of the original tree need to be grafted in order to grow the same variety. That means that every Granny Smith apple ever has technically come from a single tree. This presents a problem as the trees cannot evolve and adapt to protect from pests. Also, the most popular banana in the world, the one you see at almost every supermarket in the western world, the Cavendish, is a dying cultivar. This isn’t the first time in history this has happened as the most common banana of the past was the Gros Michel. Our incessant need to have consistency threatens the very things we love.

What nobody ITT has mentioned so far is that when you purchase seedless watermelons from a [seed catalog ](https://www.johnnyseeds.com/growers-library/vegetables/watermelon-triploid-seedless-production.html) they actually send you two packs of seeds. One pack has the diploid type one pack has the triploid type and you plant them together in the field or greenhouse so that the diploid pollinates the triploid producing seedless fruit on the triploid plants.

Edit: The diploid type is usually a variety selected because it produces a lot of flowers over a long period of time to provide pollen for the triploid plants. Without pollination the triploid plants don’t get the signal to start forming fruits. Interestingly the diploid plants will produce fruit as well (with seeds) but is easily distinguishable from the seedless fruits.

Also isn’t there a species of watermelon where there is a male and female fruit on one vine where one has the seeds but is not really edible and the others are seedless and edible?

They aren’t really seedless, the seeds just take a little longer to grow. You buy a ripe watermelon and you will see either white younger seeds or the older black ones.

Put simply it’s a cross breed of two watermelon types that when out together make a seedless watermelon.

When a daddy seedless watermelon meets a mommy seedless watermelon and they fall in love….