New Parthenocarpic Gene Pat-b

[Brent M]

Hi, my name is Brent and I'm the breeder of pat-b parthenocarpy. I've been working on it for the past 10 years.  It's been thoroughly tested, trialed, and documented.  Phase 1 of my work was to prove the capability and breed pat-b into other lines while testing those lines against highly inbred (OP), hybrids, and even other forms of parthenocarpy in side-by-side trials.  Phase 2 was to isolate the gene on the genome.  Two test grows, over 2 years, were sent to a genetics lab where we coordinated the phenotype to genotype to isolate it.  Both phases are finished. Phase 3 is awareness and release globally.  This is part of that.  I have no problem discussing the gene or my work.  Anything other than the truth, as I understand it, is counter-productive...so, open book for Q&A. 

[KaguyaCloud]

Welcome to the forum Brent! I think I remember watching your youtube video of your work a while back. What chromosome is it isolated from? Do you know the mechanism that causes this trait to arise, like SlAGL6? Is there any linkage to a physical phenotype(leaf shape, split flowers, exerted stigma, low pollen count)? What differentiates this gene from pat-k and is pat-b more advantageous than the other parthenocarpic commercial varieties? Is this gene dominant? What parent did you use?

I've come across a possible parthenocarpic variety, Rosella Cherry, within my project so I'm curious of what you've come across in your data. It's flowering and seeding behavior is very similar to Siletz from my personal experience.

[Brent M]

Welcome to the forum Brent! I think I remember watching your youtube video of your work a while back. What chromosome is it isolated from? Do you know the mechanism that causes this trait to arise, like SlAGL6? Is there any linkage to a physical phenotype(leaf shape, split flowers, exerted stigma, low pollen count)? What differentiate this gene from pat-k? Is this gene dominant? What parent did you use?

I've come across a possible parthenocarpic variety, Rosella Cherry, within my project so I'm curious of what you've come across in your data.

What chromosome is it isolated from?  I don't want to speak about the genome location even in general terms.  I'm sure it'll come out at some point in the future.

Do you know the mechanism that causes this trait to arise, like SlAGL6?  This one may be a bit complex to simply pick a term that will answer your question.  You hear descriptors like "facultative", "obligatory", "stimulative", "vegetative", "enrironmental", "genetic", and others even with different interpretations of each.  I will answer in a way I hope will be clear and I'll let you tell me what you'd call it.  Pat-b will make a tomato on almost every flower, every truss, always.  It doesn't need flower stimulous, pollination, fertilization, or any environmental influence/connection.  It will produce in any environment from high heat to very low temperatures even when pollen isn't viable.  I prefer to use one professor's description "genetic parthenocarpy".  How would you describe it after my description?

Is there any linkage to a physical phenotype(leaf shape, split flowers, exerted stigma, low pollen count)?  No, there's no pleiotropic effects.  Normal in every aspect of plant structure as related to parental influence. I've bred it into all know tomato types.   

What differentiate this gene from pat-k? If I remember (without researching again), pat-k is/was thought to be a derivative of pat-2 and was disproven later, or perhaps lost or not duplicated??  As far as I know, pat-2 (Severianin) continues to be the only really viable potential up until now.  I've trialed against pat-2.  No comparison.  In fact, I don't hear about much anymore including pat-2.  There's also no known parthenocarpy in any patent that we've been able to find.

Is this gene dominant?  It appears to be incomplete dominance, or if you prefer semi-dominant, with additives towards parthenocarpy.  I used to feel like it was recessive until I had a conversation with the geneticist. I'm in the process of testing it.  I hope that video is completed within 2 months (small sample). 

What parent did you use?  I will tell you that I believe it resulted from a mutation after heat-stressing, water-stressing, and crowding.  I had bred many inbred cherry/slicer lines with the intent to pick winners better able to handle our heat.  You know, if it lives, it goes to the next generation.  There were 10 crosses with each cross having 50 plants, 5 plants per container.  Of the 500 plants (ish), in the F2, one plant seemed to have mutated in one of the crosses.  So, more specifically, it was 1 in 50 of one of the 10 crosses. 

Can I ask?  Why the verification on every post?  It's seems restrictive especially when I answer correctly and it keeps saying I didn't.  :O)

Thanks.

[Adrian]

I have seeing a stranger thing!
For one of my crossbreeding in F1, the most long and horned fruits was the fruots with the less seeds quantity and the mosts cordiforms was the mosts rich in seeds.
The mutations sun and ovate can influnced the seeds quantity in the fruit?

[KaguyaCloud]

"I will answer in a way I hope will be clear and I'll let you tell me what you'd call it.  Pat-b will make a tomato on almost every flower, every truss, always.  It doesn't need flower stimulous, pollination, fertilization, or any environmental influence/connection.  It will produce in any environment from high heat to very low temperatures even when pollen isn't viable."

I would probably describe it as inherent/intrinsic parthenocarpy, since you have described that it doesn't require any external factors to trigger fruit set.
What happens when tomatoes with this trait experience drought/nutrient stress? Is there 100% retention or can the undeveloped fruits still get aborted? What are the differences in yields when compared to lines without this trait? Is there a trade off (ie more fruit set but smaller fruits)?

"No, there's no pleiotropic effects.  Normal in every aspect of plant structure as related to parental influence. I've bred it into all know tomato types."

By bred do you mean producing F1s or making isogenic lines via backcrossing?

A few more questions. Why post about pat-b to the Open Source Seed Forums when it seems that your intention is to patent the pat-b gene? Do you have any contingencies in case you aren't able to proliferate this gene on a large scale?

[Brent M]

I would probably describe it as inherent/intrinsic parthenocarpy, since you have described that it doesn't require any external factors to trigger fruit set.
What happens when tomatoes with this trait experience drought/nutrient stress? Is there 100% retention or can the undeveloped fruits still get aborted? What are the differences in yields when compared to lines without this trait?
By bred do you mean producing F1s or making isogenic lines via backcrossing?

A few more questions. Why post about pat-b to the Open Source Seed Forums when it seems that your intention is to patent the pat-b gene? Do you have any contingencies in case you aren't able to proliferate this gene on a large scale?

What happens when tomatoes with this trait experience drought/nutrient stress? Is there 100% retention or can the undeveloped fruits still get aborted?  Flowers don't drop most of the time.  I mean, in abusive winds or knocking them off, sure.  At times, the ovary will remain small, but start growing again later.  I see this when there's a lot of fruit set.  I "feel" like the plant is expressing that it's taxed so it's taking a break.  Not very scientific, eh?

What are the differences in yields when compared to lines without this trait?  Fairly similar when pollen is viable in ideal situations.  But, still, even when pollen is viable, many things that affect pollen will pause fruit set in normal tomato.  For example, high winds, rain, high humidity, temporary fluctuations in temperature.  Pat-b continues through those.  So, in ideal situations, it's still better.  In so-called hostile evironments, it's significantly more.  I'll use one case.  In higher temperatures, normal tomatoes stop production.  Pat-b doesn't. 

By bred do you mean producing F1s or making isogenic lines via backcrossing?  I'd like to be careful with my terminology as I'm self-taught and not had formal education or guided tutoring.  "Bred" is the word I use that indicates me transferring consistent pat-b capability into other tomato types such as cherry, paste, grape, slicer, beefsteak, determinate, indeterminate, and dwarf and selfing till inbred.  This was the main point of the initial "proof" part of of imparting the gene (and documenting it via video/photos) and any difficulties that it may present as well as separating pat-b from OSUs pat-2 lines via trials.  Or I should say seeing if there were differences.  I didn't know for some time, but now I do.  Selections in F2 with strong pat-b were always available and remained throughout the following selfed generations...mostly.  With hybrids, until last year, I'd made an assumption which I'm finding isn't exactly true.  Since I thought pat-b was recessive, it meant any cross of pat-b x pat-b would generate 100% pat-b (any generation). So, I never saw a need backcross.  Now, I have good examples of pat-b trait expression in two lines to test--an F3 and an F6 back to my F8+. The F3 expressed exactly as it did in F2.  The F6 expressed exactly as it did F2-F5.  I always perceived this as evidence of a single, recessive trait.  So, the line crosses, or backcrosses, I am evaluating now.  My initial observations are that F3 x F8 is less expressive than F6 x F8.  It sort of leans towards the incomplete dominance with additives towards parthenocarpy.  I will say, I'm still evaluating, but ultimately, I'm feeling strongly that an F8 x F8 will still produce 100% parthenocarpic capability regardelss of trait dominance. 

Why post about pat-b to the Open Source Seed Forums when it seems that your intention is to patent the pat-b gene?  I mentioned pat-b in another thread (here) and was encouraged to open another thread.  My ultimate intention is to responsibly release the genetics world-wide where I know it'll be available. There are tons of ways that can happen and I'm open to all of them.  I'm not tied to a philosophy, but to an end-goal.  I respect both thoughts of making it available to everyone to use openly (gifting my work) and those who want to protect their own hard work (patenting).  I'm not opposed to patenting and recovering some of my investment, as long as it is released responsibly.  I'm in the final Phase 3--awareness and global dispersal. 

Do you have any contingencies in case you aren't able to proliferate this gene on a large scale?  I do.  Keeping in mind my intention stated above, I have some thoughts to engage responsible breeders.  A case needs to be made to preserve the source so it's not patented and shelved for greedy intentions.  That was the intention of Phase 1 and 2.  It's pheno and geno-documented.