# Line breeding

> Line breeding is a mild form of inbreeding in which plants are mated within a family, often back towards one outstanding ancestor, to concentrate its traits while limiting inbreeding.

- Canonical: https://genetixbay.com/knowledge/glossary/line-breeding.html
- Also written: linebreeding, line-bred, line breed, line work
- Glossary category: Genetics and breeding · Evidence: Established
- Status: Draft: awaiting expert review · Updated: 2026-10-31
- Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay cannabis glossary"

Line breeding means keeping matings within one family or line, usually so that offspring stay closely related to one superior ancestor, without the full intensity of [selfing](https://genetixbay.com/knowledge/glossary/selfing.md) or repeated [full-sib crosses](https://genetixbay.com/knowledge/glossary/sib-cross.md). The aim is to concentrate that ancestor's good [alleles](https://genetixbay.com/knowledge/glossary/allele.md) while keeping [inbreeding](https://genetixbay.com/knowledge/glossary/inbred-line.md) moderate.

## In practice

A cannabis breeder might have one exceptional female. Instead of selfing her, the breeder crosses her to a selected male, picks the best sons and daughters, crosses them with each other and occasionally back to her (if she is kept as a clone), and keeps several family branches going in parallel. Branches can later be crossed together to restore vigour.

Line breeding is the patient middle path between [outcrossing](https://genetixbay.com/knowledge/glossary/outcross.md) everything and inbreeding hard. It depends on keeping enough families and records: which plant came from which cross, and how each branch performed.

## Don't confuse with

- **Backcross**: a specific, repeated cross to one recurrent parent; line breeding is broader.
- **Selfing**: the most intense inbreeding.
- **Line (market use)**: "a line" can mean any seed family; line breeding is a method.

## Related terms

[Inbred line](https://genetixbay.com/knowledge/glossary/inbred-line.md), [Backcross](https://genetixbay.com/knowledge/glossary/backcross.md), [IBL](https://genetixbay.com/knowledge/glossary/ibl.md), [Sib cross](https://genetixbay.com/knowledge/glossary/sib-cross.md), [Selection](https://genetixbay.com/knowledge/glossary/selection.md)

## Read more

- [Backcrossing, IBLs and stabilisation](https://genetixbay.com/knowledge/breeding/backcrossing-ibl-stabilisation.md)

## Sources

1. Allard RW. 1999. Principles of Plant Breeding, 2nd edition. John Wiley & Sons, New York. ISBN 978-0-471-02309-0