Breeding New Fruit Tree Landraces

Ha like this guy.
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@Justin one last thing to consider about OP is that it cannot readily be used if the selective pressure is too strong. A little bit of selective pressure and OP can, if slowly and haphazardly, shift a population towards expressing the trait being selected for, but too much pressure and OP is likely to fail.

This is because (1) recessive traits, (2) the difference between F1s and F2s. Unlike controlled breeding, where so long as you have the parents characterized correctly you can get recessive traits to express every time, OP is just a probabilities game as to if you’ll get expression–probabilities that can get pretty bad in higher ploidy plants. Similarly, while the F1 generation is often a kind of midpoint between parents, the F2 generation is highly variable and can have individual traits much closer to the original parents.

Both of these are critical if the selection pressure is high. I’ll use citrus as the example. For me in zone 8, the vast majority of citrus varieties will be killed by winter freezes. So any citrus I plant are going to face very strong selective pressure for cold hardiness.

The point about recessive should be easy enough. For example, there’s some evidence that deciduousness is a recessive trait in citrus. Obviously, being deciduous makes a huge difference in cold hardiness. If a large percent of your non-expressing carriers of deciduousness are going to get killed each winter, you’d really, really want to know which ones they are so you can protect them long enough to backcross and get your deciduous trait to actually express. You simply can’t do that with OP seedlings.

Now, for the business with F1s and F2s, consider this. Were I to just open pollinate cold hardy (CC) citrus and edible citrus (EC), I’d lose all the seedlings every year from ECxEC, naturally, but also ECxCC, since the midpoint in cold hardiness between CC and EC isn’t low enough for them to survive my winters, and only my CCxCC would survive. But CCxCC is inedible, so I’ve gained nothing, I’ve introduced no new genetics into my population of CC. The only thing I could do is put all the seedlings into a huge greenhouse until they are big enough to fruit, and then plant the second generation. But, that second generation of OP seedlings would be a huge mess of crosses, and the ones that would then survive the following winter would be dominated by (CCxCC) x (CCxCC), which, again, isn’t what I want. I don’t even really want much (CCxCC) x (CCxEC), for various reasons (I’ll miss any recessive traits in EC, and also it only takes a little CC ancestry to make fruit quality terrible, 3/4 ancestry is guaranteed to be inedible), I want (CCxEC) x (CCxEC), but very, very few of my seedlings will be that F2 generation, and I won’t even know which ones they are until that second generation itself matures and I can taste the fruit and make guesses as to which ones might be carrying some genes from EC. With controlled crosses, I’d know that every seedling was an CCxEC, I’d only need a greenhouse a quarter the size, and my F2 generation would be pure (CCxEC) x (CCxEC), which is the only F2 combination that has any hope of having the cold hardiness of CC and the fruit quality of EC. With OP, I have to protect four times as many seedlings, at least, and the second generation would have, at best, one sixteenth of it being the cross I actually want–and I’d have no idea which plants they are. After waiting for that second generation to mature, and then a few more years so the fruit quality actually presents (citrus fruit quality is much lower the first few years), I could then cull all the citrus that were not edible, and then wait another year for the next batch of OP seeds, since the previous year’s seeds would have been mostly pollinated by the far more numerous culls. What’s more, since I’ve spent so much time growing out seedlings that eventually got culled, or seedlings whose children I grew out to cull, I’ve wasted most of my population on plants that are dead ends. The number of actual crosses between plants with the right genetics quite small. All that work, with four times as many plants starting out, and an extra decade or so of time, and I ended up making only a handful of crosses of the right genes? That’s a recipe for failure, because I don’t need just one or two (CCxEC)x(CCxEC), I need many of them if I’m to hope to get that magical combination of the cold hardiness close to CC and the fruit quality close to EC. I need to maximize (CCxEC)x(CCxEC)s to even have a chance of success. In other words, I need to ditch OP, selectively cross CCxEC, protect those seedlings, and then make as many F2 crosses as I possibly can.

Breeding is hard, OP makes things way, way harder. And my example is just an idealized thought experiment. In the real world, even the controlled cross method is extremely unlikely to succeed. Cold hardiness isn’t just one trait, certainly not just one gene, and fruit quality is even more complex, so the actual number of seedlings and generations required could be staggering. Seedling vigor needs to be selected for as well, as does resistance to root rot (longer and wetter winters make root rot much more of an issue here than in Florida, even in well drained soil). The proportion of seedlings from OP plants that would just carry, not even express, traits for cold hardiness, seedling vigor, root rot resistance, and the numerous traits for fruit quality, without carrying traits for poncirus oils (foul tasting and acrid) or early bud bread (late frost danger), is vanishingly small. And those seedlings, being such a small part of the population, would then just cross with the wrong plants and lose the combination of genes we need, because, remember, we need the F2 generation for actually expressing all these traits. Not only do you need a unicorn to appear in a sea of horses, but you need at least two unicorns to not only appear, but somehow find each other and mate. Even with a population in the millions of seedlings, it’ll probably never happen.

And even that isn’t the whole story. Breeding is really hard. I’ve left out one crucial detail: nucellar seedlings. Remember, most citrus, including the majority of edible citrus, and an even higher proportion of cold hardy citrus, do not make crosses, even when pollinated. They produce seeds that are clones of the mother plant, with only a tiny percentage being actual children of the parents. An OP population of cold hardy citrus crossed with edible citrus, after two generations and decades of work, would just be a population of cold hardy citrus clones, with one or two actual seedlings mixed in, none of which would have any chance of expressing the right traits (if the vast majority of your F1 generation isn’t even F1, but clones of the mother, then you’ll never get an F2).

We make controlled crosses and clone out and graft the results because it is, by far, the most effective way of both preserving rare genetics and of attempting to create new and better plants. OP is a cudgel that will destroy most of your hard work. And breeding with the goal of establishing a landrace is literally breeding away your genetic material.

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I like to breed plants so I found this thread interesting. Citrus sounds like a tough cookie to crack. My first thought is screw this let’s do some gene splicing.
With crispr technology it should be easy to do.
Be optimistic. I wanted to improve the flavor of primocane fruiting black raspberries and it took me one cross to do it.

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Yeah, it’s not very friendly to breeders. But the payoff is definitely there–a good citrus fruit is really pretty exceptional. And at least citrus is culturally forgiving. So long as they have lots of heat, some good sun, dry feet, and you feed them amply, they do just fine. Up here, they are basically disease free, and will probably remain that way for a long time (most citrus disease are vectored by things that also don’t like the cold).

And citrus doesn’t have weird ploidy stuff like most other fruits do though.

A niffy trick with citrus is also that the fruit has so many uses, “good quality fruit” ends up being a pretty darn wide term. Extremely highly acidic and low sugar would be a bad fruit quality in a raspberry, but we absolutely love it in a lime. Yuzu is dry, bitter, sour, and has almost no flesh or sweetness, but the rind is super aromatic so it’s worth growing just for that.

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Read over your post earlier. Very nice! I would definitely think about making further crosses, especially if primocane-fruiting is recessive.

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Then maybe there’s not that much to worry about. But if you wanted to create an SI fruit tree landrace and are specifically worried about this issue, then one solution would be to ask people from cultures who already do it. Also another way to protect a population is to now and then introduce some individuals from another landrace, keeping the genetics topped up. This is actually very common in traditional landraces so far as I can see. For example in the traditional landracing cultures I’ve looked into like in the Andes, Africa, and Laos, there’s specific culture to share seeds over long distances. The crops I specifically remember in this context may not be SI, some specifically have low rates of outcrossing like rice, and potatoes were another, tetraploids and diploids - I don’t know if they’re SC or SI or both but there’s a lot of outcrossing I think. I don’t think the aim was for the new ones to cross with the old, but this was in a context where a family might be growing something like 6~10 different landraces of the same crop, and considerably more across the whole village, so some mixing would be bound to occur through outcrossing, and this would mean some level of genetic input to the landraces over time. Also while the potatoes were grown clonally, there would be some percentage of ‘volunteers’ emerging from seed and if their tuber phenotype were similar enough, they’d then become part of the landrace, even if not knowingly. So even such predominantly clonal populations were topped up genetically over time.

With modern landraces we can do this consciously, and some people specifically advise this. Also like I said, if there’s more than 1 person interested in the area, you can share the work, which means you don’t just have to rely on 1 person to take care of an entire population. And even with annual crops, you can keep a much bigger breeding population than you can grow in 1 year if you simply stagger seed production. You can plant different seed batches in different years, harvesting seed from each, so that your seed stock is much more diverse than just a single year’s seed harvest. So, these are 3 ways of increasing/maintaining higher diversity.

Interesting. Makes sense to me.

Yes, I did understand your point. I hope you also understood mine. The clonal population is like a library. Similar to a genebank - genetics frozen in time that can be accessed and used to revive or create new, living dynamic systems. This is why genebanks are so useful for creating new landraces. Even more so now that so many landraces are being decimated, pushed to extinction by commercial entities.

Well, not necessarily. I know in mainstream modern breeding, there can be an attitude of looking for specific genes, then trying to get just that specific gene into a line one is working on, and using DNA markers and so on. One doesn’t have to do that with a landrace approach. Did you watch the video I shared? That’s a great example. He started that evolutionary population of wheat with 2,000 varieties! That’s quite extreme and it’s totally possible to start with a far smaller number, especially with fruit trees. But anyway it’s an approach which is quite different for hunting for single genes.

And yes, as I keep saying, there will be an initial decrease in diversity. That’s totally fine! That’s a normal part of natural selection.

Great!

I find that extraordinarily unlikely. Most specifically because I have personally seen and eaten yuzu of numerous different phenotypes, fruit varying considerably in colour, size, skin texture, flavour and so on. I have even eaten 3 very different yuzu sold by 1 single farmer.

To back up my direct experience with an academic reference, here’s a quote from the paper ‘Cultivar identification of ‘Yuzu’ (Citrus junos Sieb. ex Tanaka) and related acid citrus by leaf isozymes’:

The center of origin of the ‘Yuzu’ is presumed to be the upper region of the Yangtze river and was spread widely into the southern areas of China. It was introduced in Japan from China via Korea during the Man-yo period, about 750 AD (Taninaka et al., 1981). After introduction, ‘Yuzu’ produced various progenies which are cultivated as local cultivar. They formed a special group of acid citrus in Japan. Cultivation of them is more commonly performed in Japan (Swingle, 1967).

[…]

There was much confusion concerning the interrelationships among the ‘Yuzu’ and related acid citrus cultivars, since many local cultivars were considered to have arisen during long cultivation periods (Taninaka et al., 1981). These cultivars have originated in a variety of ways including selection from open pollinated populations and mutation from existing cultivars.

You can also find a variety of named yuzu cultivars in Japan, and Japan isn’t even the only place to search for varieties - they are popular in Korea also, for example.

Personally I love to just squeeze the juice into water and drink it with nothing else added. Also lovely squeezed over food or used in sauces etc. The skin is also prized.

Yes. Though I have heard of some nice successes also. The same goes for crossing with green tomato species. It can take a few generations to get a delicious landrace, as I mentioned before.

Not necessarily. For example one landrace approach is to wait for the 3rd generation to start selecting for flavour, the first 2 letting the environment do the selection.

Well I know for a fact that that is simply not true for other species. I know of people who have extended the range of numerous species via the method I have been describing. I know it is far less common as a method, but I know it works. And that’s in the modern context. But this has been very common throughout history even. Not necessarily by this method of deliberately starting with a hybrid swarm - by slower methods, by which we have seen domesticated crops spreading across the globe. But starting with a hybrid swarm represents an accelerated method of that basic principle through which the various domesticated species have spread into new areas for as long as farming has existed. The method of mapping genes and all that, is extremely new. And most certainly not the only way!

Sure, I never said it was easy :slight_smile:

On what evidence are you basing that view? I would say that in general, landraces differ from heirloom varieties in particular on exactly that point - there is an obsession for keeping heirlooms ‘pure’, frozen in time since when they were often bred by breeders and sold in the seed catalogues, some back to the 18th century. But landraces are often far more fluid than that, and often containing many genotypes even within SC populations. The focus of traditional farmers in times past was on phenotype selection, not genotype. And in addition to that, as modern breeders, we can consciously maintain higher rates of genetic variation in our landraces. Joseph Lofthouse is a good example of that. And Salvatore Ceccarelli’s method of ‘evolutionary breeding’ to establish populations adapted to local land whilst maintaining high genetic diversity within populations, is another great example. I encourage you to watch that video I shared if you did not already watch it.

You seem to be ignoring all of my explanations that if wanting to create a new landrace, I’m not suggesting taking one single landrace that is not suitable for your environment, and hoping it will adapt. I’m saying get a whole bunch of different landraces, cross them all, and let your environment select from the hybrid swarm. Then also maintain a fair degree of genetic diversity after the initial settling, so that the population is better equipped to continue to adapt as the environment continues to change gradually. The latter step is anyway the same as how natural populations continue to adapt, as they have been from the beginning of life itself.

Starting from scratch domesticating an entirely wild species is a different matter. But I could give you many examples of extending the range of domesticated species using the landrace method, both by bringing together many varieties already domesticated, or by crossing with wild species. I myself even just a few minutes ago ate a delicious F2 (or F3?) tomato that was S. lycopersicum (domestic tomato) crossed with S. galapagense, a wild tomato with no history of being eaten by humans. 50% wild, entirely delicious, and grew with much less disease than all my pure domestic tomatoes. That particular one has undergone I think even no selection at all so far! I’m not saying everything is that easy - it’s not. But what I am saying is that it is wrong to think that this process has to take thousands of years.

No that’s not how I was defining it. But anyway, in the specific context which Richard complained about, I was referring to Indian people growing Indian landraces in the land they had formed those landraces in. I cannot imagine what issue he would have had with my usage if he had actually been reading this thread.

There is a spectrum. Take a look at traditional landraces and you will find phenotypic variation. For example you can find potato landraces in the Andes where the tubers will look very similar but there may be differences in the phenotypes of the leaves or flowers etc. It is up to us as breeders what phenotypes to homogenise or not.

So when you realise that it is in fact a spectrum, you can decide for yourself where you want to draw a line on that spectrum for your use of the word ‘landrace’, and I don’t really mind where you do that, but it is the content of the discussion which is important.

It’s also worth bearing in mind that higher diversity of phenotype is important during the earlier stages of creating a new landrace. You can narrow down phenotypes as you go on. It’s only really a landrace after a certain amount of adaptation and genetic and phenotypic settling has occurred. But we are after all talking about creating new landraces. That is a gradual process. And it’s really worth settling on a level of variation that may be higher than most traditional landraces since our climate is changing now so much more rapidly than in past centuries. So, it’s better to create and maintain landraces with a higher than normal level of adaptability, so, accepting a higher rate pf phenotypic diversity can be very useful for that. But like I said, it’s anyway always a spectrum.

Are you saying that after having experience with creating your own landraces, or having studied examples of people who have done so? I am guessing perhaps not. Since it directly contradicts all the evidence I know of. And I have interacted with quite a few people who work on creating landraces.

If that were the case then we should expect all wild OP populations to be homogenous. Remember how I mentioned a single accession of a single SI wild tomato species can have more genetic diversity than the entire planet’s collection of heirloom tomatoes? That would seem a good counter example. And yet they have had hundreds of thousands, or millions, of years of interbreeding.

Also what’s your point, do you disagree with what I said, that in an SI or sufficiently outcrossing OP population, the diversity is dynamic? If so then I will just agree to disagree because I think it’s just a very plain fact.

I don’t mean to be rude but your thinking seems very black and white. As if you can only imagine 1 possible way, and want to deny any other possibility. For me a far more rational response would be ‘Maybe yes, though I personally feel a better and/or faster option would be if NC State University had started an extensive modern breeding program’.

I also would have thought that my example of the plum landrace would have had at least some impact, but it seems everyone has ignored that. To remind you:

It’s hope that the genetics already exist, perhaps in ways yet to combine in a suitable manner, in the population. That’s the key. Diversity drives evolution. So, starting with maximum diversity in an outcrossing population is the fastest way to accelerate evolution. If you want to get an introduction to this kind of method, the video I shared is a great place to start, or even taking this free course would really help in getting to grips with some of the principles:

Which is why I said about not selecting for too many phenotypes at once. And also not even selecting for taste for the first few cycles when extending the range of a species. And also be willing to have some phenotypic variation in the product, like I mentioned with squashes, you can go for consistency of flavour and size, so that it is a reliable product for cooks, but allow variation in colour and shape and leaf and so on. Using these principles can really speed up the project leading to rapid adaptation.

Yes. Though landracing tetraploid potatoes can be great! But it can be nice to run OP and clone populations in parallel, keeping your favourites going as clones but still growing from seed in another plot every year or even every few years. You can keep saving the best new varieties as you go along and you might be gradually replacing your clonal populations with such new varieties, and you’re also protected that way from too much viral buildup, not having to depend on endless clonal populations. But anyway, it was the ploidy level that made me think diploid Japanese plums might be a better idea for landracing rather than European plums, not just in terms of ease for making interspecial crosses, but also due to simpler breeding even if using the single species to landrace.

Yes. I would actually recommend getting numerous different varieties, crossing them all to make numerous F1s, then crossing all the F1s with each other. Then plant all the resulting seeds out, and let the ‘race’ begin, so to speak.

Ok so here is where I differ from Joseph Lofthouse. He recommends planting everything out, letting it cross, planting out all seeds harvested, do the same again, then in the 3rd year start some selection for taste. My own approach is to take great care until one has the hybrid swarm, and only then expose them to the local pressures. This means generating the greatest genetic variation possible before exposing to selective pressures.

With his method at least some plants which did not survive to give seed, can still be in the mix as pollen donors for the fruits of other plants that did give seed. But anyway for me it is more logical to be more active - hand cross everything, make sure it all survives. And I do this by speed breeding indoors.

With fruit trees that’s not so simple obviously. But thinking aloud here, one good way might be to graft all candidates one wants to use, onto a tree or trees, in an area where they are all likely to do ok. Manually cross them all, grow out the seeds, graft them again, cross them again, harvest all the seeds, and then plant all those seeds in the target location. You could even do that one more cycle before moving to the target location, or let nature do the cross pollinating even, though manually would be more thorough, giving higher diversity.

If you wanted you could even at the 3rd or 4th round of grafting, select only the acceptable tasting fruits, and plant all their seeds. Or plant them all in one plot and the others in another, since they still might be valuable and still might give good tasting offspring. And like I mentioned, you might want to get others involved - you could split the seeds among even 10 or 100 people!

Another reason why this method can have advantages over the modern academic method.

That sounds oddly fear-based. People making new landraces doesn’t mean the world of clones is under threat! It’s really the world of landraces which is under massive threat from modern breeders’ work, so many countless landraces already having disappeared. So I think you should have nothing to fear. Also where do you think so much of that precious ‘rare genetics’ came from? :wink: There’s a hint at answering that in my above academic quote of plum landraces.

Very different direction to what I have been talking about, but… maybe creating triploids could be an avenue to explore? They’d be infertile… hmm, would fruits even form? But I mention this because, if I remember correctly, triploids can be fitter, isn’t it? Like isn’t it the triploid taro that are the only ones suited to more Northerly climates?

Are you sure yuzu is bitter? Sour yes but I thought bitter was one special thing about it being that it lacks it. Or was that just the rind?

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Is that the video with the guy from India graphing mangoes? It’s interesting he found 300 different mangoes to to graft but that’s not breeding.

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No, it’s from the previous thread where this conversation started. Would be cool if all that conversation could be moved to the beginning of this thread.

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I’m pretty sure the way you defined it was “the population is relatively reliably delicious, and relatively fit. There could still be plenty of phenotypic diversity outside of those parameters.” I quoted the place where you described your envisioned landrace because that’s where you described what you call a landrace.

Sure, to an extent, but, well, I’m pretty comfortable with being loose with words and using the broadest sense of a word if needed (and have actually had some pretty extensive arguments with Richard on that point), but even I think you’re being sloppy with what you mean by “landrace.”

I think you’re misinterpreting me here. The reason why I wouldn’t be in favor of trying the landrace/OP approach is because it is wildly inefficient and far more likely to fail.

The example of Auburn university is meant to show how hard this is. Decades of work at Auburn were only kinda successful, and before that 300 years of settlers and colonists brining in varieties and landraces from all over the place was an absolute failure. For some breeding projects with limited goals, it’s easy. For other breeding projects, like tasty but easy to grow plums in the South, it’s really, really hard, and the landrace/OP approach, if it ever worked, would probably take hundreds of years. When attempting a more difficult breeding project, OP is inefficient at best, and shooting yourself in the foot at worst.

I gave you a very detailed explanation of the mechanisms when I talked about citrus breeding. The same or similar problems exist for all fruits, to one degree or other.

Sounds idealistic at best.

Again, that’s not what I meant. Open pollination is a cudgel because while it makes doing crosses easier (no need to sterilize flowers, meticulously hand pollinate, bag, freeze pollen, embryo rescue, etc) and even feels good (“just let nature do it”) it makes breeding harder (you have no idea what the parents are, you can’t select, recessive traits are invisible unless expressed, rarer traits will get lost). If you put in a bunch of hard work collecting a ton of unique genetics, OP will wipe out most of that in a few generations.

From thousands, tens of thousands, or even millions of years of OP. Thank heavens we’ve found better ways of breeding. It would be good if we did a better job of preserving that heritage, yes, but there is no reason why we should try to use the methods that created that heritage now that we have better methods available.

It’s like building with hand tools. Yeah, it works, and a lot of really amazing buildings were built that way, and we can learn a lot from those buildings. But if we want to have nice cities and homes for everyone, and if we want to preserve those old buildings, our best bet is to use power tools and heavy equipment (and hand tools, like hammers, when appropriate–same with breeding, landraces and OP are the right tool for the job sometimes, cereal crops being a great example, fruit trees not so much). Not that it would be impossible to just use hand tools, only we’d have to give up on most of human flourishing, welfare, and progress to free up enough human resources do so. Not a good plan.

Now consider this: in a few decades of modern breeding, we’ve created Nikita’s gift and Dar Sofievsky Persimmons, Sharafuga fruit, cotton candy grapes, Southern highbush blueberries, primocane fruiting blackberries that can be grown in the tropics, sun gold tomatoes, KSU pawpaws, the most productive strains of every major cereal crop, ruby grapefruit, LSU figs, finger limes, golden rice, etc, etc. Imagine how much cool fruits and vegetables we’d have if people knew how to breed more efficiently 500 years ago. Imagine how many crops couldn’t been domesticated in that time (rather than in the thousands of years it normally takes). Imagine how many minor native fruits like maypop and mayapple and beachplum and Ogeechee lime could’ve been bred into something good enough to become commonplace and widely enjoyed?

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You do realize that the 3rd generation in a fruit tree can be 20+ years from your starting point, right? Especially because you shouldn’t select based on performance over a single growing season for most traits. If you were trying to select a pistachio or lychee landrace, 3 generations can be 50-60+ years. That’s a really long time to keep hundreds of potentially terrible (in terms of fruit quality) genotypes around.

Many citrus cultivars (garlic too) are the result of clonal selection of somatic mutants. I believe all sweet oranges arose from mutations of a single individual over thousands of years and thousands of rounds of propagation.

Selection for somatic mutants has actually been used to select for disease resistance in bananas to some effect. Thousands of tissue cultured plantlets were planted into a Fusarium-infested field and the survivors exhibited significantly greater tolerance to the disease.

The modern academic method has been able to identify the most important genes involved in cold hardiness in some crops. The problem isn’t identifying the genes, it’s getting all the right copies into a single individual.

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Interesting discussion. Ive perused it, not much more than that. I have a couple of comments -

  1. it seems to me that the species or genus im question is of prime importance. Whatever is going on “behind the curtain” is not necessarily clear, but it’s apparent looking at certain genera - Quercus, Amelanchier, Crataegus spring to mind- that some particular juju allows them to form stable “landrace” (loosely) populations in a given locale while maintaining broad diversity across locations, even proximal ones. Some plants are just inherently more cut out for this type of approach, it would seem.

  2. Since the initial discussion centered around Prunus, I thought Id mention an article I read some years back (wish I knew how to find it) about the precolonial Indian plum groves of the eastern seaboard. If I recall correctly, the author postulated based on detailed historical accounts that plums had been domesticated to a high degree and subsequently reverted to a wild unimproved form following the demise of Indian territories and the cultural and and land use practices that had maintained them. Similar cases have been made generically for a bunch of tree crops, but this was a published piece and seemed well founded.

An interesting realm of exploration, worthy of our present discussion is this transformation from wild to domestic and back again. Though we might think in broad strokes about how selection works and what it does to the gene pool, its also apparent that theres some mysterious elements there. Many of you are probably familiar with the Soviet era experiments domesticating foxes. After something like 5 or 10 generations, they had foxes that wagged their tails and barked. Ive heard it said that escaped domestic pigs will grow tusks. Not sure the details, but it seems that there are inflection points to gene expression.

I for one enjoy growing seedlings, but I dont see them as a replacement for clonal stock. Ive also found that in the niche boutique nursery trade, seedlings are often hammed up as something superior when I think the reality is theyre often not worth the bother unless your 1. curious 2. stubborn 3. have plenty of space 4. have plenty of time. Ive got the 1st three covered. As soon as I find a good seedling though, Im looking to clone it so that Ive got more on hand and can share it with others. Its really the sum total of our collective efforts that stands to make a dent in improving genetics. Thats even more the case with landraces, which are by definition of a place, of a time, and of a people. Its hard to imagine a landrace existing divorced from a community and a set of cultural practices. The fact is, those elements are in short supply in today’s world.

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Or pecans. shudders at the thought of waiting for an F3 pecan

Also one of the reasons why brazilnuts were never domesticated, and still haven’t been, despite how amazing for food, timber, and ecosystem services they are. Breeding a single generation of them takes longer than the average adult life.

One thing that’s always fascinated and disappointed me, and I think I’ve mentioned this before on this forum, was that the North American Native Americans had actually made a lot of progress in domesticating several native plants like our native amaranths, lamb’s quarters, and some grasses like little barley. But that domestication attempt was abandoned after more productive corn varieties, as well as beans, squash, etc spread from Central America. So while we got a bunch of great plants during the Columbian exchange, almost all of those were domesticated in Central America. Had the North American natives not switched over to Central American crops, we couldn’t had even more new crops in the Columbian Exchange.

To put it a la meme, “The Columbian Exchange was good, but it could have been better.”

I feel that’s got a lot to do with the romantic appeal of landraces: close-knit communities with long traditional histories and their own sense of identity grounded in the very real unique plants and animals that they grow the food they make from them. But landraces won’t bring those communities back, it’s the other way around. And, if I’m being honest, those communities only existed because they had too, life was harder back then, and everyone was poorer, there just wasn’t any other option but live in close knit communities. All around the world it’s the same trend, once people start getting enough money to live well, and productivity improves, those small communities dissolve away.

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A moderator can do that, if so inclined.

@moderators

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There’s a big difference in defining the aims of a new landrace project, and defining the term ‘landrace’. I was not defining the term ‘landrace’. But yes even traditional landraces can have phenotypic variation, as I have explained.

I’m glad you agree that it is a spectrum. Also please notice there is a difference in a population which is in the creation process of becoming a landrace, and an actual landrace. So you can still start with a hybrid swarm, which is not yet a landrace, then make it very well adapted to a specific location in which it is being grown, and with some degree of phenotypic homogeneity of the produce (which might not include leaf phenotype for example, if the leaf is not the product). At that point it can still have a lot of genetic variation, and if someone wants to say it’s not a landrace because the produce is not on the right part of the spectrum that they have chosen to draw the conceptual line at, then that’s fine, I don’t mind if they call it something else. But it would still be a population adapted to the land in which it is being grown, while containing genetic diversity within the population, and that much is completely applicable to the landrace concept.

Well I’m glad I was misinterpreting you. I mean, I’m glad to know I was wrong about that. Also, I personally don’t think that the conclusion you just made is sufficient. Specifically because, to use a fruit analogy, we are not comparing apples with apples :wink: By which I mean, you are comparing two different methods which have two different end points. For your aim, that method might be more efficient. But if ones aim would be to create a sustainable OP variety propagated by seed, perhaps the landrace method I have described would be more efficient.

Well I did give you an example of very successful plum landracing in unusually difficult circumstances, done by immigrants. And that’s without using the accelerated specific method I have been advocating for here, which should be far faster. So I would suggest not to write it off as a general method that can be effective.

And I gave you not only recent examples from annuals, but also the relatively recent plum tree landrace example which didn’t even use these more efficient methods I have described. Now I’m not saying ‘this method will work fast with every species everywhere’. But I am saying what I’m saying.

There are many collaborative breeding project, including landrace projects. So this is not mere theory. But sure, a bit of idealism can help. Hard work can be lubricated with hope and joy.

It’s a different approach. It’s harder if you are trying to use the method which this is not. It’s hard to play the guitar while you are holding a violin.

Some just hundreds, I would say. Some less I’d also say, depending on the species. And, I would include the method I have been detailing as one such ‘better way of breeding’ - much faster way to create new landraces than normal.

We have also got some great new landraces, and some great new populations heading to becoming landraces, from modern methods like the one I have been describing, which is quite different that the one you are advocating for.

Also just to take your cereals statement - we have so many grains which have been bred by modern methods, which have devastated traditional cultures and economies. And bankrupt so many farmers that India has been experiencing an epidemic of farmer suicides. Furthermore such seeds tend to be more prone to climate extremes so that has caused severe issues with crop failures. Not to mention the designed reliance on toxic chemicals and other pollutants. And then we have for example the millions of dollars invested into breeding the new patented GMO rice variety claiming ‘the highest levels’ of iron, and massively promoted by the WHO so that so much land is taken over by such seeds instead of local landraces, when in fact that expensive maladapted patented rice is up to 20 times less than traditional landrace rice varieties in India! That GMO rice is the bottom one in this list, the others are local landraces:

For more details on this and rice landraces in India in general, see:

Similarly, think about why the evolutionary populations of wheat I mentioned above, do so much better than the expensive modern-bred varieties which plague our fields.

So, the modern mainstream method is not the idealistic picture you paint. It’s really not as black and white as that. And Sun Gold tomatoes are another good example - they make people dependent on the seed corporations, since they are F1. And funnily enough, various people have been working on dehybridising it, which is exactly the kind of democratisation of food growing that I support. Here’s just one example:

Also notice how most tomatoes sold today have very little taste! All the tastiest tomatoes I have grown or eaten have not been bred by the modern academic methods like using DNA markers and so on. With only 1 exception, which is an F1 I grew to integrate some of its traits into a landrace project. And by the way I am not opposed to using DNA markers to help with breeding. I just know that you can do great breeding without it. I’ve never tasted better tomatoes than the ones from a modern landrace project. And they also grow better in the area that project is run than any commercial or heirloom tomato. And that’s not from decades of breeding even.

I also support the new domestication or other means of making, new varieties of food crop. So long as it does not result in environmental destruction. But I would much prefer if the results are sustainable in terms of people being able to save their own seeds and continue the populations on their own, without having to remain engaged with the capitalist system. Apart from many other reasons I could suggest, one simple fact is that our current civilisation is guaranteed to end. We don’t know when, but we can be sure it will.

I understand that you are opposed to the idea of a breeding method taking a long time. I also should point out to you that I qualified that by saying “one landrace approach”. And I offered an alternative method which would allow environmental selection in the first year of growing trees from seed. But anyway I know at least 1 person involved in a multigenerational tree landrace project. He’s 3rd generation.

Interesting! Could be a good candidate for re-domesticating! Also there are tomatoes which by some have been labelled ‘Solanum lycopersicum var. cerasiforme’ which some have believed to be wild, but in reality it is highly likely that these smaller fruited tomatoes have resulted from feral populations of domesticated tomatoes. So, sounds quite a similar case. (Also some have just been misidentified S. pimpinellifolium, or crosses between the two species that may have occurred in feral populations).

Yes, and I heard interestingly that they also developed various coloured fur, like domestic dogs! And I also heard that basically the domestication process was selecting against the change into… well basically adulthood. Kind of like eternal puppies!

I wonder if that might be due to interbreeding with wild boar.

The place can be where you live, the time can be years from now, and the community can be your own community. Also, it’s maybe worth realising that in traditional cultures seeds are very often exchanged. Like I mentioned in Laos, the Andes, and Africa (just because I have read more about landraces in those places in particular), where landraces would often be exchanged over distances. But yes the main thing is to make populations adapted to ones specific land and farming methods. For example, you might like to call ‘no dig farming’ a ‘cultural practice’. And one quite different to the more mainstream cultural practices of ploughing, drenching land in fertilisers and pesticides, and so on.

Was the mass genocide considerably more extensive in North America though? Because that might have meant many more crops disappeared that people today never got to hear about. Not challenging your point, but that might be a factor also.

I’ve observed the opposite trend. Of people being much happier with much less money, and becoming more and more miserable with more ‘economic wealth’. And the levels of inequality in places like the US or UK etc. for example are quite shocking. As well as the severely detrimental effect of lack of community. Especially in cities. But that’s a whole different topic.

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In case anyone’s interested, in the US, here’s a source of various fruit tree seeds:

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But less than what you started with. Which has been my contention this whole time. Establishing the landrace means reducing genetic variation. It means losing some of your diversity. Surely you accept that is the case?

This is a tautology. To create an OP variety that is propagated by seed the you should use the method of creating an OP variety that is propagated by seed. Well, yes, but you see why that’s not really saying anything, right? Your “endpoint” and your “method” are the same thing. You want a landrace, so you want to create a landrace. Ok, fine, to each their own, but that’s not an argument for landraces, that’s not an argument for anything, it’s just a blurb of circular reasoning.

One example a case does not make. I never said landraces and OP can’t work (I specifically said they do work). I said they are less efficient, less reliable, slow, don’t work well with more challenging breeding projects, and lose genetic diversity.

I’m not writing off the method, I’m just pointing out that it kinda sucks in this use case, and we have much better tools for those who are interested in breeding wonderful fruits and saving rare genetics.

Sure, but I said it was idealistic, not that it didn’t exist. There are still hippie communist communes in NorCal too, there’s still a totalitarian dictatorship hermit kingdom on the Korean peninsula, there are still people who use juice diets to “cure” cancer. The existence of these things is not an argument for their efficacy.

But our goals are the same. We both want to protect genetic diversity. We want to breed new fruits. We want those new fruits to be easy to grow, adaptable, etc. We want to domesticate wild plants and breed wild genes into domesticated plants. The only difference is you’ve added the requirement that they be open pollinated and true to seed. And I’m arguing that that addition comes at the cost of the other goals.

Good.

Now, now, before you get upset, I’m not happy that people have been harmed. But I am glad that the increased availability of more productive seed is shaking up the Indian agricultural sector (though it would be far, far better if the farmers who couldn’t adapt had some kind of social support network to fall back on). Creative destruction is a basic tenet in economics. When you make progress and create things that are better than the old things, the people that cling to the old things will get displaced. That sucks for the farmers, it’s horrible for them, and I am sad that they don’t have other options. But if they are going bankrupt, it means that not only are the landraces that they are growing extremely low producing, it also means that they aren’t high enough quality to make up for their low productivity. Sure, you, sitting in a comfy chair in the West with all the rice you could ever eat available at Walmart, say, “noo, those landraces are special and better” but the Indian moms going to market who have to feed their children disagree–they buy the rice from more productive varieties because in their estimation, it offers a better balance of cost and quality. Are you going to tell those women they are making the wrong economic choice for their families?

The Indian farmers who grow those old landraces getting displaced is unfortunate, but necessary if India is ever going to be able to feed itself. India has, by far, the lowest agricultural productivity of any major economy. By leaps and bounds. One French farmer grows multiple times more crops than one Indian farmer, despite the fact that India has a much better climate for growing crops. The same thing happened in our country, all the poor southerners got a lot poorer when combines were invented and the jobs picking cotton went away. But, I don’t think I need to elaborate why, society is better off now that we don’t need to keep 10-30% of our population tied up (sometimes literally) picking cotton.

Those old landraces can’t feed India. They need to be retired to some germplasm repository to save their unique genetics, and incorporated into new breeding programs that can take advantage of whatever might be worthwhile about them. But they should not be the main crop grown by Indian farmers, because those landraces, in the estimation of Indians themselves, are obsolete.

Beta-carotene, not iron. And it’s promoted by the WHO because a lot of people, especially children, especially children in India, are dying because they weren’t eating enough beta-carotene. Children are literally dying because of fear-mongering about this rice. Roughly 20% of all mortalities below the age of 5 on earth were because of this. Just one nutrient.

“But the landraces!” Stuff the landraces. I prefer that children live.

And I won’t suffer the pleadings of luddite reactionaries in India or elsewhere who complain about GMOs or traditional farming, not while children are being killed by their neglect and willful inefficiency. Sorry if that offends.

Sun Gold $3. I’m being so oppressed by this evil seed company…

Sorry, I’m in an overly confrontational mood after the rice thing. Yes, there are predatorial companies out there, just like there are predatorial governments, NGOs, faith communities, predatorial cults, communes, farms, etc. But a seed that isn’t copywritten, is readily available, costs peanuts, and is quite a nice variety, isn’t forcing dependence on people.

But notice how cheap they are. And if you want better tasting tomatoes, they’re available as well, at Whole Paycheck, at farmers markets, etc. But in the supermarkets, which carry what the average person wants, they are tasteless but cheap. Blame the people shopping there, not the breeders and farmers and stores that simply met the demand.

The best tomatoes I’ve ever had were hybrids, though Cherokee Purple is a close second. I live in an area where most old varieties of tomato are terrible. They rot on the vines. I’m not ok with that, and I’m glad breeders have focused so much on disease resistance rather than big, fancy tasting beefsteak tomatoes that the old growers were obsessed with.

No comment here. This is a gardening site, not a politics site, so I won’t touch this subject.

The Rapture?

This happened about two thousand years before the Spanish arrived.

So, inequality makes people unhappy, but, as you said in the next line, people are much happier with much less money? That’s not very consistent.

Also, someone’s never been to India. Or Brazil.

Sorry, I really should refrain.

I’ll stop now.

I am glad we agree here though. Best of luck in your efforts!

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And here’s a quote from that website I shared in my last comment, on their page for ‘Ocean Blue Sloe Plum Seeds’, which is rather relevant for this topic:

Selected from 100 percent immune to black knot plants our sloe plum seeds represent the highest immunity of black knot on a population level. I offer our 3rd generation seeds from the original variety ‘Plena’. ‘Plena’ was fully hardy and fruitful in Michigan however the black knot is so severe it wiped out most of the planting after 15 years. When I grew a second generation I found numerous seedlings completely immune to this. As a result, everything else was removed and now I have this seed strain to go forward as well as a cultivar for immunity to black knot.

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If for utility’s sake we bracket the piece about what a landrace actually consist of, amd instead focus on the utility of mass selection for purposes of generating seedling rather than clonal stock , its clear that there is a place for that type of work. There are some good examples to be followed too, particularly in the work around blight resistant hybrid hazels. Phil Rutter and Mark Shepard are two of the people to carry this torch in recent decades, but it really goes back to early NNGA pioneers like Fred Ashworth and George Slate. Perhaps some hazel aficionados will chime in, because my knowledge is limited. Hazels are notoriously hard to graft, and for that reason and others, breeding has focused on both improvement and stabilization with the intent of growing seedlings en masse.

Nuts on the whole have received a lot more attention in this dept. Someone (@Castanea?) might be able to offer more details, but my understanding is that heritability maps have been generated based on multi-generational trials showing which parents tend to produce offspring of similar or better quality. Ditto hickories. @Fusion_power and @Lucky_P , youre two hickory guys Im aware of. I remember reading recently that ‘Grainger’, a well known shag or shag hybrid, has produced several superior offspring in OP settings, albeit it in orchards of improved stock. Im on the periphery of this subject, so I cant offer more. But Im sure some of the nut folks here could offer some good pearls of wisdom.

The issue of reintroducing blight resistant chestnuts also springs to mind as worthy of consideration. Even if the GMO approach is ultimately deployed (as I personally think it will and should be, though I think abandoning the backcross work entirely in the 11th inning is pretty foolish), the hope is that these trees will interbreed with extant seedling populations to produce diverse offspring capable of reproducing in situ.

I also think about the appeal of feral populations of good quality crop plants. Ive been to a couple of locations where time has elapsed enough that abandoned planting have birthed impromtu landscapes of offspring. Ive always been excited and intrigued by that possibility. Its really marvelous to walk in the woods (or puckerbrush) and find yourself in something of an Eden. I sometimes think about that in relation to my own plantings, which will surely outlive me. Particularly in cases where these plantings represent isolated populations away from the influence of lots of wild offspring, it seems the possibilities are particularly apt to be interesting. Even accepting on principle @a_Vivaldi’s contention that breeding entails a de facto reduction in genetic diversity, its not clear to me that is how it occurs in the real world necessarily. Again, I would invoke some kind of juju, probably because aim simply at the edge of my understanding of such things, but theres a lot going on there, and we shouldn’t oversimplify it. Some apples have been observed to come quite true from seed, for example (transparent, golden delicious, wolf river to name a few). Apples are often touted as the gold standard of poor heritability due to their high degree of heterozygous-ness, but its clear that there are exceptions. Pulling back the lens, one could even consider the entire enterprise of apple cultivation, with all of its hybrid parentage from the Tian shin Mts. all the way to wherever you live. I sure see roadside apples all of the time that I swear Ive seen before. Some of them are even pretty good!

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Oh, I probably was rambling or ranting, I don’t mean in all cases. My point was that if you start with a broad population with diverse genetics, say a curated selection of varieties or a hybrid swarm, and then breed them with each other and make selections to the point that the population becomes something approximating a landrace, then by definition you’ve bred out a lot of the diversity that your started with. Your population will be less diverse than what your started with.

My broader point was that this is a disadvantage of the OP/landrace method. If I’m cloning cultivars and doing grafting and selective breeding, I’ll still have all my parent plants at the end of the breeding program, plus whatever cultivars I developed along the way. No loss of genetics within my population, because since I don’t use OP, I don’t need to eject anything from the population.

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No, I am opposed to the idea of making something that already takes an incredibly long time take even longer.

I suppose my biggest opposition to your idea is why waste time, space, and energy growing subpar genotypes? If I can identify the two most drought-tolerant individuals of two different drought-adapted landraces, why would I let things cross pollinate randomly instead of doing controlled crosses? I would still get a ton of garbage, but at least I know the parentage of said junk.

It sounds like you are knowledgeable about breeding tomatoes. Fruit trees are not tomatoes. According to this paper, the heterozygosity of tomatoes ranges from 0.09 to 0.19. That’s less than half that of peaches and Japanese plums. In grapes it’s 0.6 to 0.9. That means that at a given genetic locus, there’s a 19% chance a tomato plant is heterozygous at that locus. That probability in a grape is 60-90%. If I were to randomly select ten grapevines of unrelated cultivars, chances are high that there is more genetic variability within those ten genotypes than in in the entirety of the world’s tomato population.

What that means is that crossing two unrelated fruit trees is essentially the genetic equivalent of “crossing” two unrelated populations of an annual crop. Landrace annual crops are useful because most of those crops are highly homozygous. There simply isn’t that much diversity to be found. Landraces can preserve the rare alleles for certain traits missing in the majority of cultivars.

In contrast, most fruit trees have more heterozyosity than an F1 of two annual crops. That’s why clonal propagation was adopted in the vast majority of temperate fruit growing areas since ancient times. There’s a reason why the earliest domesticated fruit crops are those than can be propagated by cuttings, e.g. figs, olives, grapes. It wasn’t until a few thousand years later when grafting was discovered that apples, cherries, and pears started spreading. The Phoenicians weren’t going around planting grape seeds. Even in your plum example, they were being propagated clonally as well as by seed.

So all of their surviving sloes have the same maternal (possibly paternal too?) ancestor. That’s not exactly a win in terms of genetic variation. Most disease resistance is linked to single loci. Without adding a second, different source of resistance, there’s no reason to go further unless there’s another trait to select for.

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