High-Density Planting for Max Selection?

EBHarvey · March 25, 2015

So I'm working on quite a few lines with limited garden space, or at least limited space my wife will let me devote to tomatoes, and I was thinking that if I only need a few tomatoes to determine whether a plant contains the genetic traits I'm selecting for, is there any reason I can't super tightly-space my plants and just aggressively prune them to keep them under control but ensure I get at least a few fruit off each one?

Has anyone tried this, or really pushed the limits of high-density planting for some other purpose?

heirloomtomaguy · March 25, 2015

If you are selecting for specific traits you may run i to an issue with cross pollination. If the plants cross pollinate each other then you are starting over and the traits you were selecting for are gone. It may lead to something interesting but if your dense planting you may never get what you wanted originally.

luigiwu · March 25, 2015

Absolutely. I am limited in space (live in city) and yet I want to taste as many diff. types of tomatoes as possible. I prune most of mine to a single sucker and plant 2 in a 7gallon root pouch.

KarenO · March 25, 2015

I think plant habit will be impossible to judge with heavy pruning? With my crosses I want to see what the whole plant looks like and how they fruit without pruning. Also I can assess susceptibility to foliage problems etc. I don't have a lot of room either but bagging blossoms takes care of the cross pollination issue and selection begins at the young seedling stage to me so crowding would not give me the real picture of how my cross really is from root to tip, it's not only about fruit IMO.
I am an amateur so my thoughts are my own but my F3 plan is to limit the growout of all my selections to 3 groups this year although there are many more I want to work with in future, to plant at least triple the seeds I need, ruthlessly select for the very best, most vigorous seedlings, grow out a dozen plants of each selection, reselect and save seed from only the very best single plant of each group to carry on to F4. Repeat next year and so on.

I have a black, a dark pink and a bicoulour, all potato leaf hearts as my three groups this year.
KarenO

joseph · March 25, 2015

I know a plant breeder that will plant 100 F2 tomato plants in one pot. And cull heavily, and let each plant set one fruit. It's an easy way to select for vigor and to look for the traits that he's after without devoting a lot of space to the project. Then in the F3 he provides adequate space to those that looked promising.

Fusion_power · March 26, 2015

One of my tricks is to plant a dozen seedlings in a single hole in-ground. As they grow, select the best and coppice the rest.

ginger2778 · March 26, 2015

That's so cool! You sure dont see many PL hearts.

Quote:

Originally Posted by KarenO

I think plant habit will be impossible to judge with heavy pruning? With my crosses I want to see what the whole plant looks like and how they fruit without pruning. Also I can assess susceptibility to foliage problems etc. I don't have a lot of room either but bagging blossoms takes care of the cross pollination issue and selection begins at the young seedling stage to me so crowding would not give me the real picture of how my cross really is from root to tip, it's not only about fruit IMO.
I am an amateur so my thoughts are my own but my F3 plan is to limit the growout of all my selections to 3 groups this year although there are many more I want to work with in future, to plant at least triple the seeds I need, ruthlessly select for the very best, most vigorous seedlings, grow out a dozen plants of each selection, reselect and save seed from only the very best single plant of each group to carry on to F4. Repeat next year and so on.

I have a black, a dark pink and a bicoulour, all potato leaf hearts as my three groups this year.
KarenO

nctomat · March 27, 2015

Quote:

Originally Posted by EBHarvey

...I only need a few tomatoes to determine whether a plant contains the genetic traits I'm selecting for...

Depends what you are selecting for but I think you should be fine. Just don't select for rate of growth, disease resistance, internode length, leaf greenness, blossom end rot, fruit set per inflorescence, and other stress/nutrient related traits.

loeb · March 29, 2015

How many plants in each generation I would need to plant, for reasonable selection options.. I know that possibly 1 F1 but the rest? f3, f3, f4? I am selecting mostly for taste and quite vigorous healthy plants.. taste/flavour is most important to me. i have 2 my own crosses, and few unstable lines from different people in different stages [f1-f6] and I wonder how to manage this..

joseph · March 29, 2015

Loeb: Depends on how many genes are required to be present for your desired phenotype to manifest... And how picky you are about what you are after... I'm working on a red-podded sugar snap pea. I've planted hundreds of plants and still not found the phenotype I am most interested in. That's being very nit-picky with the genes. But it only took a dozen or so plants to obtain the phenotype of red-podded soup pea. That's a very broad easily obtained category. And the recessive genes that lead to sugar snap type pods may eventually manifest from this group.

So with a tomato project...

It is easy to screen for vigorous healthy plants as seedlings. You can screen hundreds of plants per square foot. My experience with every other species is that plants that are vigorous as seedlings continue to be vigorous as mature plants, and that weak seedlings continue to be weak as they grow. I expect that tomatoes are the same way.

In regards to taste... Supposing that I only have space to plant a dozen tomatoes per year. I can still select for better taste. To do so I could make a policy that I'm going to save seeds only from the 4 plants that taste the best each year while still meeting the health and vigor standards. This presumes of course that there is sufficient genetic diversity within the families to select for better taste. If the necessary genes aren't there to start with then the trait can't be selected for. [To reveal my personal biases, I don't think that there is enough diversity within the tomato genome for them to ever taste great, but perhaps there is enough diversity for them to not taste quite so bad.]

Red-podded Soup pea.

loeb · March 30, 2015

Ok so I have something to think about.. I am already saving seeds from best testing/performing plants, I guess I would have to plant a little more .

Beautifull pea, I made a cross for that same goal in peas

Just I want giant red podded one. I have seen one lady did that and it looked beautifull. I'me made a cros 2 years ago and seeds of f1 are still waiting, you have reminded me about them..
Here is my inspiration source:
http://daughterofthesoil.blogspot.co...e-f3-crop.html

nicollas · March 30, 2015

The method to crowd tomato plants in a pot is described by Carol Deppe in Breed Your Own Vegetables. It allows you to select for certain traits (like fruit color, leaf type, disease resistance, fruit shape ...) on a small place.

But taste involves many genes and iirc some recessive genes are important here so the more seedlings the better, and i guess it also needs some generations before taste could be reliably evaluated ?

bower · April 4, 2015

A couple of years ago (2013?) there was a thread here where Nctomatoman posted and linked a video about using 2 gallon containers and pruning to one stem/topping in order to collect seed and sample fruit from a large number of heirlooms in small space.
It may be one of the videos on this blog page - they're not visible on my cpu at the present:
http://nctomatoman.weebly.com/garden...chives/05-2013 I think the plants were fed regularly with liquid ferts. They produced normal sized fruit.

I grew a couple of F1's last year in approx 1 gallon containers, pruned down etc, and got about half dozen fruit on the small side per container - enough to save seeds so it was good enough.

I also had some F2's in beer cups I was trying to select for determinate growth habit, and waiting for them to flower - which didn't work out so well - they just got leggy instead of taking their normal shape, until I planted them out. There is for sure a minimum amount of space and resources required to get a fruit from a tomato, and maybe a different minimum amount for different traits being assessed.

I'm curious about the size of pot required to grow 100 seedlings, and how much culling, to assess the trait being sought... other than earliness of flowering, which doesn't require the kind of resources that fruit set or ripening would.

PaddyMc · April 7, 2015

I do a variation of all of the above with my own growouts. First, I mass-plant seeds (30/cell) and transplant only the most vigorous 1/3 of those to three inch pots, 3/pot, which gets culled to the two most vigorous of those. Then I plant the pairs in the ground, at WAY closer than the recommended spacing (about 14" centers, paired rows 18" apart). Then I cull down to one plant/ 14" center about three weeks after transplant. As far as how many - the more the better! In the real world, at F2 and F3, I've found that it takes me at least 20 plants per cross to get a really winning result, but if you've only got space for 5, plant 6 (you can always squeeze in ONE more

).

EBHarvey · April 13, 2015

Just an update - I put 20-30 seeds in each cell of a 72 cell tray - figured the more the better to start and I could always cull down to whatever eventual density ends up working. Couldn't believe the variation in germination rates ....I had literally every last seen germinate within 4 days of planting for a green zebra x black pear F3. By day 6 only one or two other cells had anything break the surface yet and the 3 cells with this cross looked like a week old Chia Pet.

Big surprise was a Pink Brandywine X Blondekopfchen F3 that was selected for the multiflora trait at F2 which showed rapid germination instead of the usual week or two lag I've seen with all other multi-floras. I'm hopeful that I may have separated the multiflora gene from the slow germination gene if that's possible. A missed watering killed about 2/3 of the seedlings, but I still have about 6 growing nicely, so I suppose I inadvertently selected for drought-tolerance too.

Back on topic - the current plan is to plant quads - 4 per hole - at 18" spacing and prune as aggressively as I need to in order to keep things somewhat manageable. I have a steel wire at 6 feet so I can grow very vertically. I think this is a decent compromise between maximizing genetic variation to select from and still keeping my garden "productive" from my wife's standpoint. I'll probably also gift-out a few dozen plants to friends and sample from their plants too, so overall I should be at close to 20 plants per line, with another 50+ seeds from each of the F2's in reserve should any fail to produce anything memorable and I want a do-over next year.

Thanks all for the input - and happy to see that others have really taken this to the extreme. Hopefully some day I can really go nuts with it and plant enough seedlings to really see the whole spectrum of potential diversity resulting form a cross, but for now my garden still has to actually make stuff to eat...

March 25, 2015	#1
EBHarvey Tomatovillian™ Join Date: Jul 2012 Location: CT Posts: 53	High-Density Planting for Max Selection? So I'm working on quite a few lines with limited garden space, or at least limited space my wife will let me devote to tomatoes, and I was thinking that if I only need a few tomatoes to determine whether a plant contains the genetic traits I'm selecting for, is there any reason I can't super tightly-space my plants and just aggressively prune them to keep them under control but ensure I get at least a few fruit off each one? Has anyone tried this, or really pushed the limits of high-density planting for some other purpose?

March 25, 2015	#2
heirloomtomaguy Tomatovillian™ Join Date: May 2013 Location: glendora ca Posts: 2,560	If you are selecting for specific traits you may run i to an issue with cross pollination. If the plants cross pollinate each other then you are starting over and the traits you were selecting for are gone. It may lead to something interesting but if your dense planting you may never get what you wanted originally. __________________ “Enter by the narrow gate; for wide is the gate and broad is the way that leads to destruction, and there are many who go in by it. Because narrow is the gate and difficult is the way which leads to life, and there are few who find it."

March 25, 2015	#3
luigiwu Tomatovillian™ Join Date: Jun 2013 Location: ny Posts: 1,219	Absolutely. I am limited in space (live in city) and yet I want to taste as many diff. types of tomatoes as possible. I prune most of mine to a single sucker and plant 2 in a 7gallon root pouch. __________________ Subirrigated Container gardening (RGGS) in NY, Zone 7!

April 7, 2015	#14
PaddyMc Tomatovillian™ Join Date: Jun 2011 Location: Idaho Posts: 241	I do a variation of all of the above with my own growouts. First, I mass-plant seeds (30/cell) and transplant only the most vigorous 1/3 of those to three inch pots, 3/pot, which gets culled to the two most vigorous of those. Then I plant the pairs in the ground, at WAY closer than the recommended spacing (about 14" centers, paired rows 18" apart). Then I cull down to one plant/ 14" center about three weeks after transplant. As far as how many - the more the better! In the real world, at F2 and F3, I've found that it takes me at least 20 plants per cross to get a really winning result, but if you've only got space for 5, plant 6 (you can always squeeze in ONE more).

March 25, 2015	#4
KarenO Tomatovillian™ Join Date: Oct 2012 Location: Vancouver Island Posts: 5,923	I think plant habit will be impossible to judge with heavy pruning? With my crosses I want to see what the whole plant looks like and how they fruit without pruning. Also I can assess susceptibility to foliage problems etc. I don't have a lot of room either but bagging blossoms takes care of the cross pollination issue and selection begins at the young seedling stage to me so crowding would not give me the real picture of how my cross really is from root to tip, it's not only about fruit IMO. I am an amateur so my thoughts are my own but my F3 plan is to limit the growout of all my selections to 3 groups this year although there are many more I want to work with in future, to plant at least triple the seeds I need, ruthlessly select for the very best, most vigorous seedlings, grow out a dozen plants of each selection, reselect and save seed from only the very best single plant of each group to carry on to F4. Repeat next year and so on. I have a black, a dark pink and a bicoulour, all potato leaf hearts as my three groups this year. KarenO

March 25, 2015	#5
joseph Tomatovillian™ Join Date: May 2013 Location: Cache Valley, N/E of The Great Salt Lake Posts: 1,244	I know a plant breeder that will plant 100 F2 tomato plants in one pot. And cull heavily, and let each plant set one fruit. It's an easy way to select for vigor and to look for the traits that he's after without devoting a lot of space to the project. Then in the F3 he provides adequate space to those that looked promising.

March 26, 2015	#6
Fusion_power Tomatovillian™ Join Date: Feb 2006 Location: Alabama Posts: 2,250	One of my tricks is to plant a dozen seedlings in a single hole in-ground. As they grow, select the best and coppice the rest.

March 29, 2015	#9
loeb Tomatovillian™ Join Date: Nov 2011 Location: Poland Posts: 251	How many plants in each generation I would need to plant, for reasonable selection options.. I know that possibly 1 F1 but the rest? f3, f3, f4? I am selecting mostly for taste and quite vigorous healthy plants.. taste/flavour is most important to me. i have 2 my own crosses, and few unstable lines from different people in different stages [f1-f6] and I wonder how to manage this..

March 30, 2015	#11
loeb Tomatovillian™ Join Date: Nov 2011 Location: Poland Posts: 251	Ok so I have something to think about.. I am already saving seeds from best testing/performing plants, I guess I would have to plant a little more . Beautifull pea, I made a cross for that same goal in peas Just I want giant red podded one. I have seen one lady did that and it looked beautifull. I'me made a cros 2 years ago and seeds of f1 are still waiting, you have reminded me about them.. Here is my inspiration source: http://daughterofthesoil.blogspot.co...e-f3-crop.html

March 30, 2015	#12
nicollas Tomatovillian™ Join Date: Sep 2014 Location: France Posts: 142	The method to crowd tomato plants in a pot is described by Carol Deppe in Breed Your Own Vegetables. It allows you to select for certain traits (like fruit color, leaf type, disease resistance, fruit shape ...) on a small place. But taste involves many genes and iirc some recessive genes are important here so the more seedlings the better, and i guess it also needs some generations before taste could be reliably evaluated ?

April 4, 2015	#13
bower Tomatovillian™ Join Date: Feb 2012 Location: Newfoundland, Canada Posts: 6,793	A couple of years ago (2013?) there was a thread here where Nctomatoman posted and linked a video about using 2 gallon containers and pruning to one stem/topping in order to collect seed and sample fruit from a large number of heirlooms in small space. It may be one of the videos on this blog page - they're not visible on my cpu at the present: http://nctomatoman.weebly.com/garden...chives/05-2013 I think the plants were fed regularly with liquid ferts. They produced normal sized fruit. I grew a couple of F1's last year in approx 1 gallon containers, pruned down etc, and got about half dozen fruit on the small side per container - enough to save seeds so it was good enough. I also had some F2's in beer cups I was trying to select for determinate growth habit, and waiting for them to flower - which didn't work out so well - they just got leggy instead of taking their normal shape, until I planted them out. There is for sure a minimum amount of space and resources required to get a fruit from a tomato, and maybe a different minimum amount for different traits being assessed. I'm curious about the size of pot required to grow 100 seedlings, and how much culling, to assess the trait being sought... other than earliness of flowering, which doesn't require the kind of resources that fruit set or ripening would.

April 13, 2015	#15
EBHarvey Tomatovillian™ Join Date: Jul 2012 Location: CT Posts: 53	Just an update - I put 20-30 seeds in each cell of a 72 cell tray - figured the more the better to start and I could always cull down to whatever eventual density ends up working. Couldn't believe the variation in germination rates ....I had literally every last seen germinate within 4 days of planting for a green zebra x black pear F3. By day 6 only one or two other cells had anything break the surface yet and the 3 cells with this cross looked like a week old Chia Pet. Big surprise was a Pink Brandywine X Blondekopfchen F3 that was selected for the multiflora trait at F2 which showed rapid germination instead of the usual week or two lag I've seen with all other multi-floras. I'm hopeful that I may have separated the multiflora gene from the slow germination gene if that's possible. A missed watering killed about 2/3 of the seedlings, but I still have about 6 growing nicely, so I suppose I inadvertently selected for drought-tolerance too. Back on topic - the current plan is to plant quads - 4 per hole - at 18" spacing and prune as aggressively as I need to in order to keep things somewhat manageable. I have a steel wire at 6 feet so I can grow very vertically. I think this is a decent compromise between maximizing genetic variation to select from and still keeping my garden "productive" from my wife's standpoint. I'll probably also gift-out a few dozen plants to friends and sample from their plants too, so overall I should be at close to 20 plants per line, with another 50+ seeds from each of the F2's in reserve should any fail to produce anything memorable and I want a do-over next year. Thanks all for the input - and happy to see that others have really taken this to the extreme. Hopefully some day I can really go nuts with it and plant enough seedlings to really see the whole spectrum of potential diversity resulting form a cross, but for now my garden still has to actually make stuff to eat...