How many lines should I take to F3?

Share your breeding experiments and crosses you're working on
Hatgirl
Reactions: 26
Posts: 44
Joined: Sat Feb 15, 2020 8:12 am
Location: Ireland
Contact:

How many lines should I take to F3?

#1

Post: # 47836Unread post Hatgirl
Mon May 31, 2021 6:50 pm

I am doing two grow outs
  • a dehybridization of a commercial F1 that I am finding difficult to source so I'd like to keep it around for myself
  • a grow out of a mystery plant that had several traits that didn't match its siblings so is probably a cross between the official label and some other tomato variety. It tastes just as good as the label/parent and is a bit more compact.
In each case, I saved seeds from two different fruit (I remember hearing that it was a good idea to save seeds from multiple fruits but I have no memory of why). And I sowed half of the seeds. So for the commercial one, I am sitting here looking at 30 F2 plants. For F3, should I only pick one plant and continue with that one line to F3 onward? Or should I grow out F3s from lots of different F2s?

Should my plan change based on whether its a dehybridization of a commercial, or a cross grow out?
0

User avatar
Bower
Reactions: 1629
Posts: 2248
Joined: Thu Dec 12, 2019 12:44 pm
Location: Newfoundland, Canada
Contact:

Re: How many lines should I take to F3?

#2

Post: # 47841Unread post Bower
Mon May 31, 2021 9:10 pm

Usually with a cross of dissimilar parents, the F2 generation is very diverse. So it's not unusual to save seeds from several F2 and grow out more than one line, because they're very different (but equally appealing) tomatoes.
There's a second reason for saving seed from more than one, that is as a backup, in case the line you grow forward comes to a dead end and is not what you hoped for. You might lose a key trait and hope to recover it by backcrossing to the F2 (or other generation ) sibling.
Or you might find you have half the traits you want in one F2 plant, and other traits you wanted are in a second one. In that case save both, whether you grow one line ahead or both depends on your plans and resources. You may still find all the traits in F3 from one line, but saving the other seed is a backup.
So although it's a good plan to save backups, there's no need to grow more than one line forward if you have a plant in the F2 that has the qualities you desire. That applies as well to the dehybridization as it does to the cross.

I think with 30 plants, you may well find exactly what you wanted.
I find it hard to evaluate taste from a large number of similar tomatoes at once. Will be interested to hear how it goes.
AgCan Zone 5a/USDA zone 4
temperate marine climate
yearly precip 61 inches/1550 mm

User avatar
Shule
Reactions: 742
Posts: 1585
Joined: Thu Dec 12, 2019 3:29 pm
Location: SW Idaho, USA
Contact:

Re: How many lines should I take to F3?

#3

Post: # 47853Unread post Shule
Tue Jun 01, 2021 1:59 am

@Hatgirl
I don't know the specific reason that was in mind when you heard that saving seeds from multiple fruits was a good idea, but here are some good reasons to do it:

* Different fruits sometimes have different germination rates.
* If one of your fruits got cross-pollinated, odds are good that the other fruits didn't.
* There might be mutations in a specific fruit that aren't in another.
* More seeds.
* It's fun to experiment.
0
Location: SW Idaho, USA
Climate: BSk
USDA hardiness zone: 6
Elevation: 2,260 feet

rxkeith
Reactions: 291
Posts: 270
Joined: Tue Dec 10, 2019 5:57 pm
Location: keweenaw peninsula
Contact:

Re: How many lines should I take to F3?

#4

Post: # 47877Unread post rxkeith
Tue Jun 01, 2021 9:18 am

i think you would want to prioritize which of the f2s have what you are looking for.
decide which ones are the most promising, and which ones can wait, and go from there.
how much space do you have to grow out the crosses? the more space, you have, the more
lines you can grow. with my own anna russian cross grow out, it has been hard to choose
which lines to carry forward each year. i still have f2s waiting to grow out, f3s to revisit,
and some promising f4s i want to pursue.


keith
0

User avatar
Doffer
Reactions: 12
Posts: 38
Joined: Sun Jul 26, 2020 12:00 pm
Location: Netherlands
Contact:

Re: How many lines should I take to F3?

#5

Post: # 47884Unread post Doffer
Tue Jun 01, 2021 1:12 pm

Here u can find how many plants u have to grow.
viewtopic.php?f=19&t=2059

Its all depending how many genes u want to select for!
0

Hatgirl
Reactions: 26
Posts: 44
Joined: Sat Feb 15, 2020 8:12 am
Location: Ireland
Contact:

Re: How many lines should I take to F3?

#6

Post: # 47887Unread post Hatgirl
Tue Jun 01, 2021 1:32 pm

Doffer wrote:
Tue Jun 01, 2021 1:12 pm
Here u can find how many plants u have to grow.
viewtopic.php?f=19&t=2059

Its all depending how many genes u want to select for!
Not quite. If you are breeding for recessives, once you see all the traits they should all appear in the next generation.
Also the numbers there are just the law of averages not a guarantee - just like how if you toss a coin it's a 50:50 chance it will land heads up, but you totally could toss a coin four times and get heads each time, or sow 4 plants and not get a single one with the gene you want
1

Hatgirl
Reactions: 26
Posts: 44
Joined: Sat Feb 15, 2020 8:12 am
Location: Ireland
Contact:

Re: How many lines should I take to F3?

#7

Post: # 47888Unread post Hatgirl
Tue Jun 01, 2021 1:37 pm

Thanks for the advise everyone! The commercial is a micro so it's full of recessive genes and will probably be pretty stable, so I will save seeds from multiple plants but only continue one line, and keep the others as backups.
The mystery cross - well I will see what happens in the F2! If they are all similar I will only keep one line, if they vary I will see what I like from them!

User avatar
Pippin
Reactions: 43
Posts: 43
Joined: Fri Mar 20, 2020 6:49 pm
Location: Finland
Contact:

Re: How many lines should I take to F3?

#8

Post: # 47889Unread post Pippin
Tue Jun 01, 2021 1:57 pm

Edit: posted this before seeing the latest updates from @Hatgirl. :D

It may depend also if you are having a serious breeding project in your mind or if you just want to have a seed source with ”close enough” tomatoes. I used to maintain multiple Fn cherry tomato lines just to have good quality seed source. My lines didn’t segregate that much for fruit size and the fruit color remained the same without any changes. I actually just used the same F2 seeds for several years. Then when I saw something worth saving, I moved to the next generation. Quality wise, some lines lost little bit flavor and crack resistance the further I went. This approach does not work that well with hybrids with complex background, such as Sungold.

It is good to understand little bit which traits are recessive or dominant. For example, yellow or striped tomatoes will very likely keep these qualities in all following generations if present in F1. One can also try to make some educated guesses what can be expected to see based on the fruit shape, e.g. longated tomatoes will likely stay longated, and perfectly round will likely stay round. Slightly oval tomatoes may segregate to round only if the original parents had different recessive fruit shape genes. Many recessive fruit shape genes express themselves slightly even when the dominant form is present too.
BR,
Pippin

User avatar
Tormato
Reactions: 723
Posts: 843
Joined: Thu Dec 12, 2019 3:14 pm
Contact:

Re: How many lines should I take to F3?

#9

Post: # 47902Unread post Tormato
Tue Jun 01, 2021 5:32 pm

"How many lines should I take..."

There is no "I" in "we".

We, in this community should be able to help you with some of the growouts.

There is an "Experimental" category in the MMMM swap. Save seeds (and join at your own peril).

User avatar
MissS
Reactions: 1967
Posts: 2875
Joined: Fri Dec 13, 2019 4:55 am
Location: Wisconsin Zone 5b
Contact:

Re: How many lines should I take to F3?

#10

Post: # 47920Unread post MissS
Tue Jun 01, 2021 9:21 pm

We also have a place on the forum where you can offer seeds. Why not offer some seeds and ask for help in stabilizing some of these. There are plenty of people here that enjoy helping to create some new varieties. Just be sure to ask for seeds back of those that turn out well.
1
~ Patti ~
Smile! It makes people wonder what you've been up to.

Hatgirl
Reactions: 26
Posts: 44
Joined: Sat Feb 15, 2020 8:12 am
Location: Ireland
Contact:

Re: How many lines should I take to F3?

#11

Post: # 47959Unread post Hatgirl
Wed Jun 02, 2021 5:40 pm

Other time constraints I have mean I can't take on the organizational issues around distributing seeds. I also don't participate in grow outs, or swaps. They are great! But not suitable for my circumstances.

Post Reply

Return to “Tomato Crossing/Breeding”

Who is online

Users browsing this forum: No registered users and 1 guest