Agronomy Journal - 1956 - Suneson - An Evolutionary Plant Breeding Method1.pdf (547.8 KB)
As part of my independent research, I am trying to gain an overview understanding of the protocols and history of Participatory Plant Breeding and Evolutionary Plant Breeding.
From what I can tell, Evolutionary Breeding is very much in the spirit of landrace gardening, but it’s hard to access this paper from 1956 which was one of the early efforts to describe using masses of relatively casual hybrids.
From the paper:
28 diverse varieties completely intercrossed. giving 378 separate Ft combina- tions which were blended
Nice 
I hope you share your research with us, sounds interesting!
This looks like a really important paper. It’s hard to read though! I’m having trouble dedicating the brain power to decipher what they’re saying-- maybe you can summarize it for us!
@julia.dakin I have reached a point where I’m satisfied with the new section I’ve added for Evolutionary Plant Breeding here: Plant breeding - Wikipedia
I have not been familiar with this terminology before now but it seems very useful. If you search for scholarly papers for the combination term “Participatory Evolutionary Plant Breeding”, that synthesis approach seems to be very much akin to what some folks here are working towards.
For what it’s worth, I’ve made major overhauls to the landrace article over the last couple of days as well: (Landrace - Wikipedia)
I need to let it rest and wait for any reviews, but hopefully that one would be ready to add some more plant landrace examples soon, a possible community effort.
If I understood correctly in this paper results (hybrid swarm more productive than standard variety) took longer than what Joseph has observed. Selection method in this paper isn’t detailed enough and remained vague to me. It does mention that they didn’t do much selection, but if they dont select seed plants then what did they do with seed increase over years? Do they just plant mix of needed amount of seeds and seed production favours those that make most seeds. That would explain slower process as weeding out the weakest completely would speed up the process. Besides that, it seems to be same as we do.
I think you’re correct. My understanding is that the early efforts decided as Evolutionary Plant Breeding were simple in that there was no intentional selection other than survival.
Maybe I should have started by sharing a modern link. You might be interested in this report on how evolutionary breeding techniques are being used in Nepal in more recent times in a way more similar to landrace gardening: https://cgspace.cgiar.org/handle/10568/110762
Farmers are looking for crop varieties that can better adapt to these changing conditions, and seeds of which can be saved for the next season planting. Evolutionary Plant Breeding (EPB), which creates and maintains a high degree of genetic diversity (i.e. polymorphic population), is a choice for breeders and farmers for accelerating the development of climate resilient and sustainably high-performance crop varieties
Yeah it was rather disappointing in terms of not explaining their method wasn’t it!
Since it was a seed crop - barley right? then I guess even if they simply just used a percentage of the harvest to replant next year, even randomised, that should lead to crop yield increase. Because the most productive variants would be making up an ever-increasing proportion of the seed harvested. Slower than manual selection but a nicely natural process I guess, if that is the way they were doing it, and way less work especially at scale. It might even preserve greater genetic diversity than if the seed were selected, due to inherent biases in the selectors.
By the way, I wonder about seed used for crops that animals eat. Perhaps they are more diverse and more like landraces? Maybe they are not plagued by the peculiar ‘purity’ ideals and ‘improvement strains’ ideals that human crops are?
Maybe it was just because they wanted to keep true to the method/discription of their study. I’m not familiar of barley reproduction, but I suspect they are wind pollunated so the genetic diversity wouldn’t decrease that much even if some of the least productive were left out. But I do think that some control might be necessary at the start to give genes best change to spread trough the population if they are in any way useful. Other option is to have so many varieties so that there will be enough crossing even if not all contribute. There is only so many genes plants/popolations can have in the end. I dont know about animal feeds, but it would make sense that there are less demands. They do need to have some degree on uniformity when it comes to nutritional make up.
I dont think that sheds more light to the first paper, but mixing and sowing proportion of the mix seems most likely. Second paper has so many different terms that it’s hard to keep track what is what, but it seems there are range of selection methods used from natural selection to some degree of human selection. Crops of choice (seed crops) might be reason that there is less need for human intervention, but I still think some human selection is beneficial to speed up the process.
I’m working through another recent paper and I do feel like there is a conceptual convergence that I hope I will be able to describe in writing:
https://www.nature.com/articles/s41559-021-01497-x
An alternative and more agnostic approach is (co-)evolutionary breeding (Fig. 1b) in which heterogeneous populations are created by crossing multiple parents. A well-known example is the composite cross in which multiple genotypes are combined into a single population by realizing pair-wise crosses63. The population obtained is then bulk-propagated as a whole, often in combination with a mass selection step, but allowing natural selection to relatively freely shift allele frequencies across generations. The expectation is that population productivity and robustness increase because of natural selection of locally adapted genotypes, because heterozygosity is maintained through (sometimes rare) outcrossing, and because niche complementarity may evolve between separate inbred lines, for example, through competitive divergence and resource-use specialization64,65,66,67. The composite cross thus shares many similarities with landraces from traditional farming systems68, that is, both are dynamic and genetically diverse populations that adapt to local conditions.
