The Genetics of Seedless Watermelon

The Genetics of Seedless Watermelon


The most amazing fruit of summer – seedless watermelons – are my favorite. Spears, cubes in salad with feta, even blended into agua fresca, watermelons are fabulously refreshing. But how do seedless watermelons grow? How can a fruit grow without seeds? The genetics of seedless watermelon might surprise you!

seedless watermelon

Seedless watermelons are grown through a process called triploid breeding. This involves crossing a watermelon plant with a diploid (two sets of chromosomes) pollen parent and a tetraploid (four sets of chromosomes) seedless watermelon parent.

seedless watermelonThe resulting offspring, known as triploid plants, have three sets of chromosomes. Due to this odd number of chromosomes, triploid watermelons are sterile and cannot produce viable seeds. As a result, they develop seedless fruits.

seedless watermelonTo cultivate seedless watermelons, farmers often grow regular seeded watermelons nearby as pollinators. Bees or other pollinators transfer pollen from the diploid watermelon plants to the triploid seedless watermelon plants. This pollen does not contain the necessary genetic material to produce seeds, but it stimulates fruit development.

The seedless watermelons that grow from these pollinated flowers develop small, white, and edible seed coats that are typically considered unnoticeable. These tiny seed coats give the appearance of seedless fruits, allowing consumers to enjoy the juicy, seed-free watermelon flesh.

It’s important to note that while seedless watermelons may have reduced or absent seeds, they are not completely devoid of them.

seedless watermelonOccasionally, tiny, soft, and underdeveloped seed coats may be present, but they are typically considered negligible and do not interfere with the overall eating experience.


Published by JustAddH2OTeacher

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