Still another tomato thread, male sterile, brown seed.

[walt]

Nothing against all the other tomato breeding, but I'll describe what I'm doing, why, and over the years I'll tell about success and/or failures.
I'm using the recessive brown seed mutant linked with a recessive male-sterile mutant.  So over 90% of the seedlings from the brown seeds will be male sterile.
The bs-ms, brown seed, male sterile genes are available from the Tomato Genetics Cooperative.  But they are in a tomato variety "Ailsa Craig".  "Ailsa Craig" was bred in Scotland.  I am in hot, dry, windy, Kansas, USA.  "Ailsa Craig" really doesn't like it here.  I had to get seed 3 times before I could get a ripe fruit.  And every year I get lots of good tomatoes from my garden.  So I'm blaming the variety.
But last year I finally got a couple of mature fruit from it and sorted out the brown seeds.  Yesterday I planted lots of the brown seeds, so I'm expecting to get lots of male sterile plants.
I'll be pollinating with every variety in my garden, but mostly with LA 0722, a S. pimpinellifolium that is quite heat and drought tolerant.  If I get even one hybrid, I can count on the F1 being very well adapted here.  And I'll be able to count on lots of F2 seeds.
You might think that cutting open a heterozygous bs tomato and seeing a mix of brown and yellow seeds won't be pleasant.  Actually the brown seeds only have a tiny brown spot on each side, barely noticable when I'm looking for it.  It was hard for me to seperate them out. 
In my younger days it would have been easier for me to hand emasculate tomatoes and make crosses that way.  But weaker eyes and less steady hands make male-sterility necessary now.

[gilbert]

That's really interesting! Where can I find out more about this?

[walt]

All I know about it is on the Tomato Genetics Cooperative website.  And that is enough.
If you order want seeds that are brown seed, and MOSTLY male sterile, PM me.  I haven't germination tested my seed, but I expect they are good.  I'll know in a couple days.
Or in a few months (3?) I'll have F1 seed in abundance, I expect.  But who really knows how a crop will be?

[reed]

May 12, 2018 12:31:50 GMT -5 walt said:

  Actually the brown seeds only have a tiny brown spot on each side, barely noticable when I'm looking for it.  It was hard for me to seperate them out. 

Well, that is interesting. I see something very similar to that on a fairly regular basis when saving my tomato seeds.  Most tomatoes don't have any, some have just a few, and once in a while I see it on almost all seeds of a particular fruit. 

I never liked the look of it and sort those seeds out. If a fruit has a lot of them I discard the whole thing. I don't have a good reason to think it's linked to a disease or something negative but just kind of assumed it was. 

[walt]

I doubt brown seeds are always due to this gene.  Nor to other genes either.  Some may well be due to disease, and you may be right to throw them out.  And if it not linked to a gene you want, male-sterile in my case, there is no reason to put up with it.
And in my breeding program, brown seed gene can be removed at any time, in two generations.

[gilbert]

I guess I'm not understanding this right. Is Ailsa Craig unstable? How many generations would it be able to continue producing two kinds of seeds? Is AC itself male sterile? Shouldn't at least some of the seeds in a standard packet be brown/ male sterile? Could I just pick seeds out of the packets?

And, if I made a cross in this way, would the F2 plants be all male sterile, or would some of them be fully fertile?

[walt]

Ailsa Craig is not the origional source of the brown seed mutant, nor the origional source of this male sterile gene.  It happened to be the variety a breeder was using when he learned from other source that the 2 genes are close together on the same chromosome.  So he crossed the ms with the bs and grew a huge population, and located at least one plant where the genes had crossed over and were together.    Any male fertile bs seedlings must be removed in each generation to keep this as a usefull tool.  Such male fertile seedlings are easy to identify by having good fruit set.
Could the bs seeds been sepperated in the origional seeds from tgcn?  Yes, if I had known how little the brown shows in the dry seeds.  I was expecting a bigger difference, and didn't look real close at each seed.  Looking at the next generation seed, I at first thought I didn't have the brown seeds.  But with practice, knowing where to look and what to look for, I could sepperate them.

So I planted my seeds about 2 weeks ago, outside in pots.  S. pimpinelifolium LA 0722 came right up quickly as always.  A couple days later Yellow Pear, a couple days later, Texas Wild Red Cherry and a gift from a friend who is an heirloom seed saver.  Yesterday, finally, the bs seedlings were coming up.  I do have viable bs ms seeds if anyone is interested.  The very limited litterature on bs ms tomatoes doesn't mention delayed germination, and one trial with each variety each in a seperate pot doesn't prove anything.  But I'll be watching to see how it does in future generations, in various crosses.  Either way, I'll be using it.

[philagardener]

Don't know if the brown seed becomes more prominent with age, but fresh seeds are often lighter overall.

[walt]

I'll try sorting both fresh and dry and see which is easiest.
But my crosses this year will all have yellow seeds.  No sorting browns until next year.

[walt]

My tomatoes got a late start.  They are growing and blooming well, but it is too hot for tomatoes to set.  Next cool spell, I'll be pollinating like mad.
The brown seed-male sterile tomato plants are doing very well.  So are S. pimpinellifolium LA 0722, Yellow Pear, anf Texas Red Cherry.  All are blooming.  None are setting fruit.

[steev]

I was amazed when I realized how many plants shut down with excessive heat; I'd only been aware of Buckeye; if I don't get ripe toms before peak heat, I won't see any until after; even fruits that were growing get put on "pause". Just another way we'll be affected by global warming.