Leaf Shape and Brix Research Article

[karstopography]

https://nph.onlinelibrary.wiley.com/doi ... /nph.16403

Interesting. Some Potato leaf genetics and other goodies in the link. Bigger, rounder leaves produce better fruit if Brix is the standard of better fruit. Thinner more narrow leaf plants respond positively to more light.

Some famous name heirloom tomatoes, like Brandywine, Stupice, Pruden’s Purple compared, maybe your favorite is in there. T

See what else you can tease out of the link.

[PlainJane]

So cool that there is this: Plant Genomic DNA Purification Mini Kit.
Fascinating article overall. Go potato leafs!

[Rockoe10]

That's wild! So the scientific winner is....Stupice!

Looks like if I want a successful plant, I should lean towards potato leaves

[bower]

Certainly nice to see some recognizable cultivars being studied. I can't say that I agree with the conclusion that PL actually causes the higher brix. They couldn't figure out what mechanism might produce the cause either, since photosynthesis was negatively correlated. Consider sample size of 18 cultivars (quite small) and many of the PL's turned out to be closely related which also had the highest brix. There is an obvious chance that these cultivars share the genetics for high brix, independent of their leaf shape.
Ironically I recall seeing an article some years ago that was reporting the opposite - the more serrated the leaf, the higher the brix.
So I think the jury might still be out on that.
Not to rain too hard on the parade, I'd love to see these folks do a bigger study and tell us more about the genetics of heirlooms!

[MrBig46]

I want to measure Brix. I may have read it incorrectly, but I did not find the measured Brix values anywhere. If I divide the BY value by the total yield (Stupice), the Brix will be just under 5. That's very little when I compare it to the 12-13 at Sungold. Is that really so? I ask protp that I would like to be prepared for what numbers I will probably find out in my measurement.
Vladimír

[mama_lor]

Here is the graph you want. Yes, most of them have a brix between 4 and 6, only abc potato leaf has almost 8, it's the only cherry. 6 is a solid value for a non-cherry, nothing unusual here. And that 12 value for Sungold is the best value in the best conditions in the best year, it's not the typical value. Are you growing Sungold this year? I'm curios what value you get.

brix.jpg

[Shule]

That's wild! So the scientific winner is....Stupice!

Looks like if I want a successful plant, I should lean towards potato leaves

Flavor-wise, I agree that potato leaf plants are often above-average. But, there are other advantages and disadvantages to each leaf-type. PL plants seem to be more prone to a late-season leaf curl condition (probably spread by leafhoppers, unless it's just weather damage) in my area, but I've heard PL plants are less susceptible to certain issues out East. I'm guessing leafhoppers prefer to suck from broad leaves.

[Rockoe10]

I've also heard that blight is more of a concern with PL. Though I can not confirm that

[Shule]

[mention]Rockoe10[/mention]
I'd be interested to hear about that if you learn more. I'm not sure what condition they were said to resist better than RL, but I thought it was a common fungus. I think I'm thinking of the threads where we compared Kellogg's Breakfast (RL) with KBX (PL) and people out East overwhelmingly preferred KBX in it's performance, while Kellogg's Breakfast did better for me. My KBX didn't get the leaf issue, though (no noticeable disease or stress; just stunted).

@all
I've been wondering what a PL SunGold F1 would be like. I mean, let's say we crossed SunGold F1 with a sweet PL tomato (like Medovaya Kaplya), and just kept backcrossing it with SunGold F1, retaining PL plants, until it was practically a stabilized PL SunGold.

[Rockoe10]

A PL Sungold-type variety. That sounds delicious.

I'm trying two OP varieties that are descendent of Sungold (Sungold Select II, Ambrosia Gold). Even a cross between one of these types and a PL could yield interesting results.

[MrBig46]

Here is the graph you want. Yes, most of them have a brix between 4 and 6, only abc potato leaf has almost 8, it's the only cherry. 6 is a solid value for a non-cherry, nothing unusual here. And that 12 value for Sungold is the best value in the best conditions in the best year, it's not the typical value. Are you growing Sungold this year? I'm curios what value you get.
brix.jpg

The table doesn't open for me.
Vladimír

[Shule]

...

The table doesn't open for me.
Vladimír

Can you view it if you click this link?

Can you try another web browser?

Were you logged in when you tried to view it? I don't think pictures show up unless you're logged in.

I wonder if clearing the cache might help (no need to clear cookies, too, if you do that).

[Doffer]

I think the more leaf area available per fruit (fruit size) that the brix will increase.
Which leaf shape has more surface area RL or PL?

[bower]

Some interesting discussion about PL and other traits here, and various speculations offered as to why it may have been left behind by the commercial breeders:
https://blog.seedsavers.org/blog/explor ... -structure
Generalizations about PL linkage to brix or other traits (exserted stigmas here) are likely due to the "narrow genetic pool" of traditional PL varieties. These theories tend to be disproved in the process of breeding new cultivars - then we find there's no 1:1 correlation with the associated traits. And that's a good thing, it means we can breed PL plants with any other desired traits if we want to.

[Pippin]

Thanks for interesting discussion, lots of good points and observations.

It seems to me that researchers in the original paper were more interested in the overall performance and quality of the broad leaf tomatoes than high brix alone, as they often refer to their BY parameter (BRIX by yield). Higher yied compensates average brix in this competition.

... while BRIX is used as a standard quality measure, BY is a composite value that folds in yield to assess weight (kg) of soluble solids per plant and is being used to measure commercial (grower) quality and not consumer (taste) quality

The researchers only studied broad leaf tomatoes, so the results probably applies to ”PL” tomatoes only. So the claim really should be that ”PL” plants with rounder leaflets get higher BY value than narrower leaf PL plants. Fruits from rounder leaflet PL plants are not necessarily sweeter than from other PL plants but they may have a better balance between the brix and yield. Not sure if the researcher are really trying to proof that PL tomatoes are sweeter than RL tomatoes. They didn’t even study RL plants.

Funny thing is that if the researchers’ theory was true, then PL heart tomatoes should rank low in such measurements as they typically have longated, narrower leaves (cf. whispy). I think that the gene that makes the fruit longer, also longates the leafs. It feels simply wrong to me if one fruit type cathegory was left out of this game.