What Are F1 Plants & Seeds: How & Why of F1 Hybrids
I’ve noticed many ordinary growers are confused by the term F1 hybrid and some have completely wrong ideas about what F1 hybrids are and what the advantages and drawbacks of F1 hybrids are.
My Favourite Variety – Sungold Tomatoes, an F1 Hybrid
What Are F1 Hybrid Seeds?
An F1 hybrid is simply the result of breeding two different strains of a variety to produce a third variety. The term ‘F1’ just stands for Filial 1 or ‘first children’.
Why produce F1 Hybrid Seeds?
This simplistic example should make it clear as to the why and how of F1 hybrids.
Imagine you’re a plant breeder and you’ve developed a new variety of tomato ideal for growing in the British summer. It’s taken years of patient seed selection and is now stable, breeding true generation to generation.
Over in the greenhouse you’ve another variety of tomato. It’s taken years to develop and is now stable. Its big advantage is that it is blight resistant. Useless for growing outdoors but otherwise fine.
These stable plant varieties are known as pure lines because they breed true without lots of variants growing, they are pure. This is important to consistent results from hybridisation.
You then hand-pollinate to cross your two pure lines together and produce seed. With luck you now have a plant that is great to grow outdoors and is blight resistant. This first cross is the F1 Hybrid.
Producing F1 Hybrid Seeds
To produce a supply of these F1 seeds the breeder has to maintain two pure true varieties as well as a stock of breeding plants that are usually hand pollinated.
This is clearly far more expensive than producing non-hybrids.
Often with F1 hybrids you have a bonus in that this cross will grow really well. It’s a phenomenon that is well known called hybrid vigour. This only happens in the first cross. If you use the F1 hybrid to produce a second generation – which is known as an F2 – you lose this benefit.
Producing Seed from F1 Hybrids
So, at the end of the season we save some of the seeds from our blight-resistant, outdoor tomato and next year grow them. What a disappointment! Some will be blight-resistant, some great for outdoors growing but not both. None will be as vigorous and productive as their parent.
An F1 is not a ‘pure line’ and stable. It contains genes from both parents and how these will combine in the offspring is a matter of random chance.
There is no benefit for the home grower in saving seed from F1 Hybrids.
Benefits of F1 Hybrid Seeds
- The hybrid combines the best of both parents and excels both of them
- The hybrid will be stable and ‘do what it says on the tin’
- The hybrid will most probably be a vigorous and productive plant.
- The breeder knows he has an ongoing market for his seed in that people can’t just buy a packet and then produce their own in subsequent years.
Drawbacks of F1 Hybrid Seeds
- The seed is more expensive. Either the packet price is higher or the quantity in the pack reduced but they will cost more.
- You cannot seed save and produce your own plants. You are forced into buying seed when it runs out.
- If the breeder stops production for any reason you are stuck. Once the seed stock is gone, it is gone for good unless you know the parentage and have stocks of the parent plants’ pure lines.
Genetic Modification for F1 Hybrids
To bust a myth I’ve come across – F1 hybrids are not genetically modified. It is a completely natural plant developed and bred conventionally.
F1 Hybrids are Just a Money Maker
It’s true the seed producers make money from the hybrids which they need to cover the cost of development and production. But people will only buy hybrids that offer distinct advantages over open pollinated varieties that they can grow for free.
You literally ‘pays your money and takes your choice’
F1 hybrids explained. How they are produced, the benefits and drawbacks of F1 hybrid seeds and plants discussed and myths de-bunked.