How Do You Make Seedless Tomatoes?

Seedless tomatoes, also known as parthenocarpic tomatoes, are primarily created through a specific crossbreeding process involving plants with particular genetic traits.

Based on the provided reference, seedless tomatoes are made by crossing a tomato plant containing at least one parthenocarpic gene (used as the male parent) with a male sterile tomato plant also containing at least one parthenocarpic gene (used as the female parent).

Understanding the Key Traits

Making seedless tomatoes relies on combining two important genetic characteristics in the parent plants:

Parthenocarpy

• What it means: Parthenocarpy is the natural or artificially induced production of fruit without fertilization of ovules. This means the fruit develops without seeds.
• Role in seedless tomatoes: Tomato plants with parthenocarpic genes can produce fruit (tomatoes) even if pollination or fertilization doesn't fully occur, resulting in few or no seeds.

Male Sterility

• What it means: Male sterile tomato plants are unable to produce viable pollen.
• Role in seedless tomatoes: Using a male sterile plant as the female parent in a cross ensures that self-pollination (where the plant pollinates itself with its own pollen) does not happen. This guarantees that any resulting fruit comes from the intended cross with the parthenocarpic male parent.

The Crossbreeding Process

To produce seedless tomatoes using this method, plant breeders carefully execute a controlled cross:

1. Select the Parents:
   • Male Parent: Choose a tomato plant (Lycopersicon esculentum) that has at least one parthenocarpic gene and produces viable pollen.
   • Female Parent: Choose a tomato plant (Lycopersicon esculentum) that is male sterile and also contains at least one parthenocarpic gene.
2. Perform the Cross: Pollen is collected from the male parent and transferred to the stigma of the flowers on the female parent. Since the female parent is male sterile, there's no risk of unwanted self-pollination.
3. Develop the Fruit: The flowers on the female parent, once pollinated with the desired pollen, develop into fruit.
4. Obtain the Seedless Offspring: The seeds produced by this cross, when planted, will grow into tomato plants that produce seedless (or nearly seedless) tomatoes.

Here's a simple way to visualize the cross:

By combining the parthenocarpic trait (for seedless fruit development) from both parents with the male sterility of the female parent (to control the cross), breeders can effectively create plants that yield seedless tomatoes.