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#81
Legumes / Re: Overwintered runner beans ...
Last post by Carol Deppe - 2026-07-16, 04:19:46 PMHere in maritime Corvallis Oregon, runner beans in an area that is not tilled in fall will overwinter most winters. (The ground does not usually freeze more than an inch or two deep. The roots are usually below that.) However, the overwintered plants didn't give beans any earlier than those planted from seed in spring. They weren't as productive as the same space planted from seed in spring, either.
#82
Plant Breeding / Re: Mutation breeding using ca...
Last post by Carol Deppe - 2026-07-16, 01:52:01 PMI made some caffeine-resistant mutants of the fungus Schizophyllum commune back in the 1970s. Don't remember much about it now. Also have used EMS (ethyl methane sulfonate) and Xrays as mutagens. This was all in the context of having a full-scale molecular bio lab with access to an Xray setup, etc. Usually mutagens are seriously dangerous. However, it should be possible to use caffeine as a mutagen even if your ability to weigh it isn't great.
Usually when you use a mutagen on a new system, you have to figure out the right dose of mutagen for your system. Even if the paper you were using as reference was using caffeine as a mutagen on solanum seeds, it would be a "different system" when you were trying to mutagenize seeds of a different solanum species.
You usually start off doing one experiment just to get the approximate range of concentrations of mutagen. Most mutagens will kill all the biological material at a certain concentration, at a bit less will cause so many mutations you have an unworkable mess with multiple mutations in everything and too many viability problems. At a just right concentration you have a mix of material with much with no mutations and much with just one mutation per biological entity each. At a yet lower concentration of mutagen you have to look hard to find any mutants. And below that you don't get enough mutants to be worth looking for them. You also always have a no mutagen control. Maybe the seed was all dead.
Usually it takes one preliminary experiment to figure out the roughly approximate range of mutagen levels. Then when you do the mutagenizing for real you still use a few different concentrations. Just a narrower range than the first time. If you do it many times on some runs the optimal level of mutagen is one amount and sometimes slightly different. This is even if you have your own fancy biochem lab with an analytical balance. Biology ain't physics. Us biological entities are an unruly lot.
If you are doing it that way it should work even if your ability to weigh things isn't stellar. And if you go get yourself a better balance, you will still need to establish the workable range of concentrations of mutagen in your system yourself, as well as use multiple concentrations in any mutagenizing run to accommodate the variability of everything when doing biology.
Usually when you use a mutagen on a new system, you have to figure out the right dose of mutagen for your system. Even if the paper you were using as reference was using caffeine as a mutagen on solanum seeds, it would be a "different system" when you were trying to mutagenize seeds of a different solanum species.
You usually start off doing one experiment just to get the approximate range of concentrations of mutagen. Most mutagens will kill all the biological material at a certain concentration, at a bit less will cause so many mutations you have an unworkable mess with multiple mutations in everything and too many viability problems. At a just right concentration you have a mix of material with much with no mutations and much with just one mutation per biological entity each. At a yet lower concentration of mutagen you have to look hard to find any mutants. And below that you don't get enough mutants to be worth looking for them. You also always have a no mutagen control. Maybe the seed was all dead.
Usually it takes one preliminary experiment to figure out the roughly approximate range of mutagen levels. Then when you do the mutagenizing for real you still use a few different concentrations. Just a narrower range than the first time. If you do it many times on some runs the optimal level of mutagen is one amount and sometimes slightly different. This is even if you have your own fancy biochem lab with an analytical balance. Biology ain't physics. Us biological entities are an unruly lot.
If you are doing it that way it should work even if your ability to weigh things isn't stellar. And if you go get yourself a better balance, you will still need to establish the workable range of concentrations of mutagen in your system yourself, as well as use multiple concentrations in any mutagenizing run to accommodate the variability of everything when doing biology.
#83
OSSI / Re: OSSI breeding funding
Last post by Carol Deppe - 2026-07-15, 04:03:18 PMQuote from: Steph S on 2026-07-10, 07:21:43 PMI read through it and am really impressed with how thoughtful this is about the real needs of independent non funded breeders, to get your seed ready to pledge and release.
Kudos.
We on the OSSI board had a lot of fun designing the grant program. I especially enjoyed the lines where we said +/- we didn't give a #$%&! about whether you had graduated from high school or college or had any formal schooling at all. What fun! #84
OSSI / OSSI GRANTS for INDEPENDENT PL...
Last post by Carol Deppe - 2026-07-15, 02:41:41 PMFriends,
OSSI requests proposals for our new grant program, "Independent Plant Breeders Developing Organic-Adapted Open Source Varieties." The grants are designed explicitly for variety development by independent plant breeders. The paperwork is minimal and the use of funds is very flexible.
Applicants must be at least 18 years old and live in USA, Canada, Australia, or New Zealand. Proposals are due September 15. See our Request for Proposals and Application at https://osseeds.org/ossi-plant-breeders-grant-application/
Carol Deppe, Chair, Board of Directors, OSSI
OSSI requests proposals for our new grant program, "Independent Plant Breeders Developing Organic-Adapted Open Source Varieties." The grants are designed explicitly for variety development by independent plant breeders. The paperwork is minimal and the use of funds is very flexible.
Applicants must be at least 18 years old and live in USA, Canada, Australia, or New Zealand. Proposals are due September 15. See our Request for Proposals and Application at https://osseeds.org/ossi-plant-breeders-grant-application/
Carol Deppe, Chair, Board of Directors, OSSI
#85
Tomatoes / Re: F1s for the People! 2026
Last post by Tim DH - 2026-07-15, 01:02:34 PMHi Steph,
I've also got interested in the genetics of truss architecture. One of the F1 ideas I'm pursuing is to try and raise the productivity of 'tasty' cherry tomatoes. Obviously, with cherry sized fruit, the truss configuration has a significant effect on production.
The multiflora trait (Barry's Crazy Cherry) appears to be recessive. Tatiana lists some interesting Multiflora, or multiflora like, varieties. The trait might come from Lycopersicon humboldtii in which case different Multiflora varieties (from different breeders) could have significantly different parentage, which would be good for making vigorous F1s (although there is a high frequency of Ildi lookalikes!) Also L. humboldtii might confer some useful disease resistance.
Like you, I think ''Ultimately it's all about the food '' and I've already set my heart on working with Early Red Bush F1s next year. ... but a Multiflora F1 trial is very tempting. .... That 'argument' should keep me amused this Autumn! (Oh, and I also fancy doing a Dwarf Tomato Project F1 trial. Because the DTP kept very good records, its easy to sort out varieties which are not significantly related.)
I've also got interested in the genetics of truss architecture. One of the F1 ideas I'm pursuing is to try and raise the productivity of 'tasty' cherry tomatoes. Obviously, with cherry sized fruit, the truss configuration has a significant effect on production.
The multiflora trait (Barry's Crazy Cherry) appears to be recessive. Tatiana lists some interesting Multiflora, or multiflora like, varieties. The trait might come from Lycopersicon humboldtii in which case different Multiflora varieties (from different breeders) could have significantly different parentage, which would be good for making vigorous F1s (although there is a high frequency of Ildi lookalikes!) Also L. humboldtii might confer some useful disease resistance.
Like you, I think ''Ultimately it's all about the food '' and I've already set my heart on working with Early Red Bush F1s next year. ... but a Multiflora F1 trial is very tempting. .... That 'argument' should keep me amused this Autumn! (Oh, and I also fancy doing a Dwarf Tomato Project F1 trial. Because the DTP kept very good records, its easy to sort out varieties which are not significantly related.)
#86
Plant Breeding / Mutation breeding using caffei...
Last post by Geum - 2026-07-15, 03:06:31 AMI read a paper called Estimation of genetic variability, mutagenic effectiveness and efficiency in M2 flower mutant lines of Capsicum annuum L. treated with caffeine and their analysis through RAPD markers where, as the title suggests, they subjected Capsicum annuum seeds to a 1% solution of caffeine which lead to mutations in the plants. In particular the paper shows pictures of mutated flowers in the M2 generation.
I tried it myself on Solanum villosum seeds, without the phosphate buffer, and with no success. No seeds germinated.
Perhaps it's due to the lack of the phosphate buffer or maybe I overshot the caffeine concentration as I used a cheap scale to measure the caffeine.
Has anyone tried this or does anybody know any other relatively safe mutation breeding techniques?
I tried it myself on Solanum villosum seeds, without the phosphate buffer, and with no success. No seeds germinated.
Perhaps it's due to the lack of the phosphate buffer or maybe I overshot the caffeine concentration as I used a cheap scale to measure the caffeine.
Has anyone tried this or does anybody know any other relatively safe mutation breeding techniques?
#87
Nightshades / My Solanum sect. Solanum cross...
Last post by Geum - 2026-07-15, 02:53:54 AMHey everyone, I'm currently working on the following crosses of Solanum sect. solanum (mother x father):
- S. scabrum x S. nigrum -- growing F1 plants
- S. scabrum x S. nitidibaccatum -- growing F2 plants
- S. scabrum x S. sarrachoides -- waiting for fruit to develop
- S. scabrum x S. villosum -- from what I read this shouldn't be possible but out of 3 pollinated flowers, 2 are forming fruit. The hybrid will likely be a sterile pentaploid due to differing ploidy
- S. villosum x S. retroflexum -- waiting for fruit to ripen
- S. pimpinellifolium (wild tomato) x S. sarrachoides -- both are diploids but it likely won't work due to how genetically far away they are, either way it doesn't hurt to try
S. scabrum is a valuable parent because unlike the rest it has large and firm berries. However they don't taste good raw. If they're not bitter, they're largely tasteless with a slight hint of tomato flavor in them.
The goal in that case will be to get a plant with the taste of the father while preserving the fruit size and firmness of the mother.
My S. villosum is red and is practically not sweet at all, tasting strongly of tomato (or tomatillo). Crossing it with the sweet S. retroflexum could lead to something interesting.
- S. scabrum x S. nigrum -- growing F1 plants
- S. scabrum x S. nitidibaccatum -- growing F2 plants
- S. scabrum x S. sarrachoides -- waiting for fruit to develop
- S. scabrum x S. villosum -- from what I read this shouldn't be possible but out of 3 pollinated flowers, 2 are forming fruit. The hybrid will likely be a sterile pentaploid due to differing ploidy
- S. villosum x S. retroflexum -- waiting for fruit to ripen
- S. pimpinellifolium (wild tomato) x S. sarrachoides -- both are diploids but it likely won't work due to how genetically far away they are, either way it doesn't hurt to try
S. scabrum is a valuable parent because unlike the rest it has large and firm berries. However they don't taste good raw. If they're not bitter, they're largely tasteless with a slight hint of tomato flavor in them.
The goal in that case will be to get a plant with the taste of the father while preserving the fruit size and firmness of the mother.
My S. villosum is red and is practically not sweet at all, tasting strongly of tomato (or tomatillo). Crossing it with the sweet S. retroflexum could lead to something interesting.
#88
Tomatoes / Re: F1s for the People! 2026
Last post by Steph S - 2026-07-13, 04:24:21 PMHey Tim,
Well for sure, if I have any OPxOP stable F1's I wouldn't pass it up.
I'm actually very curious about truss architecture and how that is expressed in an F1, because one of the features of RxPL is a sturdy, relatively small truss of 5-6 fruit, similar to the Rodney.
I'm looking at Mazarini with a branched very rambling truss, some of which will be dropped instead of setting, and wondering whether the sturdy truss gene would be consistently expressed in the F1.
So if I can get a cross opportunity for those two, I would give the F1 space for production as I did with this one, just to see how the truss pans out.
Ultimately it's all about the food, so if an F1 makes that easier I'm for it.
I have a bit of a problem with indeterminates, they just grow too big for my space and are way more work than determinates, requiring a ton of handling pruning tying etc. So any reproducible F1's are still likely to make way for selecting a determinate OP.
Also I have a habit of 'stirring the pot' as the growout goes along - if I see a trait missing which could be brought in from another plant I never hesitate to cross unstable lines. So the majority of F1's that come through here are not reproducible. They may still be worth the space for production reasons though! So I wouldn't count it out, especially if indets actually do turn out to be more resistant to Alternaria.
It is really nice to have bred a couple of stable parents, so for example if RxPL fulfills the promise of being tasty and extra productive, it might be worth growing at a farm here or in a greenhouse that's better designed for indets. And would be easy to produce the F1 seeds since Rodney is a staple for me while Pervaya Lyubov is a common grow for friends who are food producers.
Also if I can figure out the logistics of getting my stable varieties OSSI pledged, the F1's would be OSSI too, and if they help anyone to grow a food bounty in this stressed world, that would be a good thing.
Well for sure, if I have any OPxOP stable F1's I wouldn't pass it up.
I'm actually very curious about truss architecture and how that is expressed in an F1, because one of the features of RxPL is a sturdy, relatively small truss of 5-6 fruit, similar to the Rodney.
I'm looking at Mazarini with a branched very rambling truss, some of which will be dropped instead of setting, and wondering whether the sturdy truss gene would be consistently expressed in the F1.
So if I can get a cross opportunity for those two, I would give the F1 space for production as I did with this one, just to see how the truss pans out.
Ultimately it's all about the food, so if an F1 makes that easier I'm for it.
I have a bit of a problem with indeterminates, they just grow too big for my space and are way more work than determinates, requiring a ton of handling pruning tying etc. So any reproducible F1's are still likely to make way for selecting a determinate OP.
Also I have a habit of 'stirring the pot' as the growout goes along - if I see a trait missing which could be brought in from another plant I never hesitate to cross unstable lines. So the majority of F1's that come through here are not reproducible. They may still be worth the space for production reasons though! So I wouldn't count it out, especially if indets actually do turn out to be more resistant to Alternaria.
It is really nice to have bred a couple of stable parents, so for example if RxPL fulfills the promise of being tasty and extra productive, it might be worth growing at a farm here or in a greenhouse that's better designed for indets. And would be easy to produce the F1 seeds since Rodney is a staple for me while Pervaya Lyubov is a common grow for friends who are food producers.
Also if I can figure out the logistics of getting my stable varieties OSSI pledged, the F1's would be OSSI too, and if they help anyone to grow a food bounty in this stressed world, that would be a good thing.
#89
Tomatoes / Re: Montana Tomato Project
Last post by William Schlegel - 2026-07-12, 02:06:00 PMIn the old fenced garden the number 365 tomato I selected last year looks odd. It might have something like curly top virus. No other line in the same garden has that look though so maybe its the only susceptible one.
Tomatoes are finally starting to bloom fairly well after the late frosts. It's also hot now. Will see how much fruit sets. Next weekend may be too hot for making crosses and I haven't started yet. Hopefully the summer will cool down a bit.
Tomatoes are finally starting to bloom fairly well after the late frosts. It's also hot now. Will see how much fruit sets. Next weekend may be too hot for making crosses and I haven't started yet. Hopefully the summer will cool down a bit.
#90
OSSI / Re: OSSI breeding funding
Last post by William Schlegel - 2026-07-12, 02:03:02 PMInteresting will have to do more research into that one. Though wouldn't be timely for this funding unless could do two generations a year.