Unusual statement regarding PL's

[tomatoguy]

I ran across this statement while perusing loveapplefarm.

"Its potato-leafed foliage makes it disease resistant."

This statement is referring to the variety Matina. Normally, I would have just attributed this to the plethora of misinformation that is distributed by so many websites about tomatoes. Even my favorite vendors are guilty. What made me wonder, though, is that my friend Perry who has been growing my plants out for years has the same opinion about PL's. His evidence is strictly anecdotal but he definitely prefers the PL's for that reason.

I realize that "tolerant" is the preferable term to "resistant" but the above quote is not mine.

I would like to know if anyone else shares this opinion. I have grown a lot of varieties over the years but I would guess only about 10-12 PL's. I have not seen any evidence of better disease tolerance in PL's.

mater

[Spatzbear]

Strangely enough, this season has seen PL plants hardier / more disease resistant than RL plants. I hadn't noticed this in previous years, but this year it's obvious. The RL plants have mainly dried up / crispy foliage, or are totally dead. PL plants are still fairly green and pumping out tomatoes.

I must add that all plants are nearing the end of the season and we had very strange and extreme weather this summer. But one glance into the tomato patch, and you'd notice mostly PL plants. And I have to say that the majority of my plants were RL.

It isn't proof that PL are more disease resistant, but this is just my observation this year in my patch.

[Suze]

Originally Posted by tomatoguy

I would like to know if anyone else shares this opinion.

I do, to some extent. I'm a big fan of PL varieties in general, and grow several each year. I've observed some slight difference in tolerance to early blight (and especially septoria).

Same with rugose varieties, which I also love to grow.

[Tomstrees]

I can say PL's beat blight in my garden this year -

Tom

[nctomatoman]

It is a hard generalization to make, kind of like a one point graph, because the numbers of regular leaf varieties far exceed potato leaf varieties. From my experience, I have fewer potato leaf varieties go down without giving me even one fruit than regular leaf, but is it statistically significant, and have the proper controls been run? And, last year, all of my varieties struggled with a host of diseases (primarily bacterial wilt and fusarium wilt) - dwarf, regular leaf and potato leaf.

Interesting - back in 1900, Livingston made a case for their variety Potato leaf doing particularly well on clay soil and in drought, assuming that the large unserrated foliage had some beneficial effect.

I think that unless I see a controlled study - say, 10 plants of five different potato leaf varieties and 10 plants of 5 different regular leaf varieties all growing in one garden plot with uniform sun and soil and watering, it is all supposition.

[MsCowpea]

Potato leaf varieties are also some of my favorites. I have also read that some think they are more tolerant to foliar diseases --unfortunately in my garden I have never seen them exhibit any added disease tolerance . As a matter of fact many are the first to succumb to diseases.

This year Crimson Carmello (reg leaf) was the first tomato plant that I could see a real difference to foliar diseases (bacterial spot) and EB. Though infected it kept producing and producing long after I have ripped out all the other plants. Momotaro was also good at 'tolerating' diseases though not as good as CC.

As far as potato leaf, Earl's Faux seemed to hold up better than most.

[carolyn137]

For many years I've made the comment at several places online that in my experience with my gardening zone and my conditions that most of my PL varieties have withstood the various foliage diseases much better than the RL varieties.

And I'm pretty sure that it's from me that Cynthia at Love Apple Farm picked up on that b/c we used to post at the same site years ago.

Not everyone has had the same experience but Lord knows with about 2000 different varieties grown and many of them PL's, b/c I love them, I still see the PL's standing tall when the RL's are down and out at the end of the season.

Craig, I don't get it with your seeing lower yield with the PL's. I just cannot see any reason for that and actually I think you're the only one I've ever seen mention that. Do you have any idea why that might be true for you?

[nctomatoman]

Carolyn, I didn't say I get lower yields - I said that there are inherently far less potato leaf than regular leaf varieties. I've never correlated yield with leaf shape - in fact, I don't like to contemplate generalization of yields for any particular variety at all, since there are simply too many variables location to location, season to season, technique to technique.

[carolyn137]

Went back anmd read Craig, my boo boo in reading too fast.

******

(I think that unless I see a controlled study - say, 10 plants of five different potato leaf varieties and 10 plants of 5 different regular leaf varieties all growing in one garden plot with uniform sun and soil and watering, it is all supposition.)

*****

But that's exactly what I did for so many years when I grew my tomatoes at the old farm. I always had at least two plants of each variety and heaven knows I always had more than 5 PL varieties and more than 5 RL varieties all in that same field that were treated exactly the same and exposed to the same weather in any one season/

And the PL's still did best re foliage diseases.

[elkwc36]

My experience is alot less than most commeting on here. I have to agree with Carolyn. As an example after six years of growing Brandywine Sudduth I've never had one plant go down. And after reading Carolyn's opinion I watched mine last year and I only lost one PL. So far I can see the difference. Will keep watching and comparing and after another 3 years should have a good comparison.

[dcarch]

Last year, the final surviving plant was a PL.

http://www.tomatoville.com/showthrea...ghlight=darwin

dcarch

[eyolf]

Craig's idea of some sort of blind test makes sense, but maybe one should find seeds of those few varieties that seem to exist in both PL and RL forms to include. I have both types of "Polish", but won't be doing a growout again anytime soon. I did grow them side-by-each last year and found the yields, disease resistance, flavor, etc. pretty much indistinguishable.

Actually, I cringe when I see statements like we saw about PL's...I have seeds for a couple of small-fruited PL's that are almost as rampant as cherries and never really succumb to fungal diseases even here in my garden (where Septoria and Alternaria usually cause plenty of trouble). OTOH, small, wimpy plants like Kotlas or Kimberley usually look pretty ragged at the end of the year.

[Mantis]

I reckon PL's hang in there a bit better. No proof, nor studies, just observation. This is in a very dry climate BTW

[carolyn137]

maybe one should find seeds of those few varieties that seem to exist in both PL and RL forms to include. I have both types of "Polish", but won't be doing a growout again anytime soon. I did grow them side-by-each last year and found the yields, disease resistance, flavor, etc. pretty much indistinguishable.

*****

Are you referring to the Polish C that i distributed a few years back that was RL and asked folks not to distribute it to others? So you now have both PL and RL Polish C? I ask b'c I don't know of any of the other Polishes that exist in two leaf forms.

There's also a PL and RL version of Cherokee Purple and folks who have grown both say they aren't the same as far as other traits go.

The problem I see is one that Keith and I have been discussing for several years.

I always thought that the major way that one could get a PL variant from an RL was to go from the homozygous RL or the heterozygous RL form to the homozygous recessive PL form, which looks like this:

let C = RL
let c = PL

CC is homozygous dominant and RL
Cc is heterozygous and RL
cc is homozygous recessive and PL

And those would be single step spontaneous mutations.

But as Keith has pointed out, and I now agree with him, the change could be due to deletions, to loop inversions and other molecular DNA changes in addition to spontaneous mutations.

And what that means is that the change from RL to PL could be accompanied by changes that aren't so obvious such as taste, DTM and more. Sure, the fruits might LOOK the same but are they?

So these days I have a slightly different outlook when someone says they have a PL version of a variety that should be RL.

As far as Polish C goes, I have grown both leaf versions side by side and don't see any difference in fruit traits or taste, but again, for me the PL plants are more tolerant to fungal diseases, and I know that isn't the experience of everyone.