Selecting for Success: What’s the Buzz about Potato Pollinations?

When we talk about pollination, buzzing bees often steal the spotlight. However, in the world of potato breeding, a different buzzing tool is used– the electric toothbrush. But why, you might ask?

The pollen on potato flowers has its challenges in pollinations. It clings to the anthers, making it difficult to collect for breeding purposes. To work around this issue, potato breeders at the Cornell University Potato Breeding Program and similar institutions across the country use electric toothbrushes. These vibrating devices are carefully placed on potato flowers, helping to dislodge and collect the stubborn pollen into a collection tube. This process is done on all clones considered for use as a potential male parent in the breeding program for the season.

Simultaneously, the female parent potato clones are being grown. Once these plants flower, pollinations begin. Pollen gathered earlier is carefully shaken into the cap of the collection tube. Then the stigma of each flower is gently dipped into this pollen. Each pollinated flower cluster is labeled with the appropriate tag, an important step in ensuring the identity of the cross done on each flower.

The successful pollinations form small berries that look like small green tomatoes. However, these berries have an affinity for dropping from the plant, making them unusable because their cross is unidentifiable. To prevent the valuable crosses from being lost, paper bags are carefully placed over the berry-bearing clusters. In this protective covering, the berries are safely collected and harvested. Once harvested, seeds from these berries will be put into storage to be planted the following growing season.

In 2023, the Cornell breeding program made several crosses with a specific goal in mind: developing potato varieties resistant to the pale cyst nematode (Globodera pallida). One of the standout sources of resistance in this endeavor is the variety Innovator because it has relatively higher levels of resistance compared to other varieties. This is attributed to the presence of the Gpa5 resistance gene. Innovator is a successful parent with 25 named varieties as its progeny. By incorporating Innovator in their breeding crosses, the program aims to create new potato clones that not only have resistance to nematodes but also exhibit favorable agronomic traits.

This blog was originally posted to PAPAS website at https://potatonematodes.org/

Supported by the USDA National Institute of Food and Agriculture award number 2022-51181-38450