Inadvertent selection, serendipity and emergent traits in Vicia faba

Adaptation Projects
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Last year I grew out a big row of hyper-diverse broadbeans, and harvested the seeds. Not everything ended up in the harvest tarp - some seed was shed onto the woodchip mulch.
Later, I raked the woodchips into the path so I could re-spread it on the followup crop (garlic) once it had emerged.
But the fallen seed sprouted in the path, no big issue, I let it go, thinking "these are good survivors, and probably inputing life into the soil. I used other woodchips and let these broadbeans grow on.
This week i harvested the garlic, and cut some of the broadbeans whose pods had started to dry down, throwing them back onto the bed to dry. Tonight, i went to pick up the pods before tomorrow’s rain.
Several ideas formed as I was harvesting:
My initial thought was to throw these back into the wider genepool (there’s another big row yet to harvest), but i noticed that some of the pods has dehisced (dropped their seed). and a bit of an ad hoc survey of the harvest indicated that many of the pods were thin, and easily split. This it makes sense: the varieties that easily shed their seed would of course be the volunteers in this sub population. Not a great trait if you want to harvest dry seed as a pulse, so my second thought was to reject this seed.
Luckily, it took me a bit of thinking time to harvest the pods, and i mused on how this year, we harvested very young green pods, about little finger size (US=pinky size) and cooked them whole in a napoli sauce. Yum!
they were nearly all toothsome, with only occasional pods having tough strings.
Now, I recalled a trait from my snowpea breeding days, that dry pods that were easily crushable were also low fibre snow peas. - a great way to select for snowpea pods using dry mature pods from a mixed population.
Perhaps the same trait is reflected in broadbeans?
A bit of pod grinding revealed that this sub-population had a lot of the ‘crushable pod’ trait, indicating low fibre development compared to the boiler plate toughness of some of the pods i harvested from the wider population last year.
Perhaps there is a culinarily useful ‘baby faba’ project to work on?

My take home is landrace selection isn’t just about survivorship - we need to be careful we aren’t selecting for an unwanted characteristic without knowing about it.
Second, often there may be a silver lining in our failures - one grower’s rejects may be another’s grail.
Pay close attention. Don’t hurry. enjoy the diversity.
g

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Thanks for posting this! I’m always interested in stories of inadvertent selection, since it is always operating “behind the scenes”. By becoming more aware of the possible results of such selection, we can greatly improve our plant-breeding ability.

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Very interesting Gregg. In the UK there are broad beans selected for eating pod and all. I remember seeing them on the seed racks when I lived there. They were sometimes referred to as snow beans, but mostly they used the British term mangetout. Despite this last being a French ‘word’ I never heard it used in France when I lived there.
As an aside, the bush bean Dragon Tongue has so little fibre in the pod that when it dries down the pod just crumbles away when you crush it. That makes it great as a home grown snap bean but useless for market because it goes quite limp once picked.

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I didn’t know of such a broadbean! there i go, re-inventing the wheel again.
We have really enjoyed them here this year as tiny pods. slightly weird mouthfeel, but I’m working on that too, trying to rediscover a ‘shiny pod’ trait i observed some years ago.
g

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Thank you for sharing Gregg, that’s a very interesting discussion to follow

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