How do plant breeders obtain seed for a seedless watermelon?
This is accomplished by making several different types of crosses between watermelon plants. Without going into a long genetic lesson, it first begins by doubling the number of chromosomes (threadlike bodies in cells that contain genetic information) in a normal watermelon plant. This is done by chemical treatment. This new plant is referred to as a tetraploid because it now contains four sets of chromosomes instead of the normal two. When the tetraploid plant is bred back, or pollinated, by a diploid plant, the resulting seed produces a plant that is basically a "mule" of the plant kingdom – one that produces seedless watermelons. The flesh of this melon is usually firmer than seeded varieties, because the usual softening of the fruit around the seeds does not occur.
This is accomplished by making several different types of crosses between watermelon plants. Without going into a long genetic lesson, it first begins by doubling the number of chromosomes (threadlike bodies in cells that contain genetic information) in a normal watermelon plant. This is done by chemical treatment. This new plant is referred to as a tetraploid because it now contains four sets of chromosomes instead of the normal two. When the tetraploid plant is bred back, or pollinated, by a diploid plant, the resulting seed produces a plant that is basically a "mule" of the plant kingdom – one that produces seedless watermelons. The flesh of this melon is usually firmer than seeded varieties, because the usual softening of the fruit around the seeds does not occur.
