If you save seeds, there’s a good chance you don’t harvest seeds from every single fruit on every single plant in your garden. Instead, you pick the best fruit from your favorites plants and save those seeds. That’s selection. And, while you are gardening, maybe you pull out and remove the plants that exhibit off-colour leaves or bolt early. That’s rogueing.
Selection improves the genetic integrity of the crop and rogueing is the process of examining a crop and removing unwanted individuals. Plants can be rogued for a number of reasons: off-type color, shape, or plant growth characteristics, presence of disease, insect damage, or low vigour. Timing is important when it comes to rogueing. It is crucial to remove undesirable individuals from the plant population before flowering, so they don’t cross-pollinate with the remaining seed crop.
For certain crops, like squash, it’s not realistic to expect to remove all the off-types before flowering as you may not notice them until the fruit has started to develop. However, other crops, like lettuce, have gone through nearly all their stages of growth before they flower. Read more about selecting and rogueing for lettuce seed.
Alternatively, you can select for traits you want the progeny to exhibit, such as early flowering, certain colours, fruit shape or plant stature, disease resistance and hardiness. Selection can also be used to create new varieties. Some growers start with a hybrid, “destabilize” it by continuing to save seeds and grow it out, and then embark on the often-painstaking multi-year process of selecting for the traits they want the new variety to exhibit.
This is how the Bizhiki tomato, one of the Vegetable Seed Producers Network (VSPN) varieties, was created. Ontario farmer Cory Eichman started with the hybrid tomato variety ‘Buffalo’ and selected for a great tasting greenhouse tomato that doesn’t crack. After selecting fruits that met these criteria and harvesting seeds from them year after year, he eventually had a uniform, bright red, globe shaped, open pollinated tomato that grew to 5-8cm with no cracking. He named it ‘Bizhiki’, the Anishnabe word for Buffalo.
Another VSPN variety, the ‘Lipstick’ pepper, is an early producer, ready to harvest a full week ahead of other bell peppers at 70 days. The fruits should be selected for a pimiento-type, oblong shape at about 4-5 inches long. They should be medium to thick walled, crunchy, and juicy. Since these peppers should also produce well in cooler growing conditions, any plants that exhibit low vigour or are slow growers in cool weather should be rogued out of the seed harvest population.
Whether you grow a few tomato plants in your backyard, or have a huge operation devoted to seed production, removing off-type plants and selecting only the best plants and fruits is crucial to maintaining high quality seed in your collection or store. Continuous observation, from the seedling to harvest stage, is also key to selecting the best fruits from the top-performing plants and removing off-types before they can cross-pollinate.