Saving true to type broad bean seeds

[Jang]

I’m sure I could research this but urgent action is required!

If I want to save specific varieties of broad beans are there any manageable methods? If I bag some flowers will they successfully self-fertilise within the bags or do they need a larger population such as might work under fleece for a whole bigger batch of plants?

[triffid]

The are self-fertile, but do benefit from a large population. I don't believe inbreeding from a single generation would do them much harm though.
Depending on how many seeds you want, you could bag some flowers (quite fiddly because of their orientation), or cage/cover them in insect netting or other fine material. Fleece would work but could the plants get hot under that?
Best of luck.

[Jang]

Thanks Triffid. I have put a couple of small bags on experimentally. A to of my beans seem to be beginning to flower while still quite short. I can't remember whether that has always happened.
Yes, mesh makes more sense than fleece. I'll see what I can arrange tomorrow.

Are you trying to isolate any of your broad beans in a similar way?

[triffid]

I'm noticing flower buds on short plants, too. May be the bright weather we're having.

Of the plants I'm growing for seed, I'll bag about 50% of the flowers and leave the rest to the bumblebees. That way I can keep true seed while also allowing some cross-pollination to occur, on the same plant. Might not be a very smart way but it's the best I can do with the equipment I have this year.

[Veggie]

I've been wondering about staggering the flowering of broad beans so that only one variety is flowering at any time. Not sure how practical that is though!

[Jang]

I guess it depends on how many varieties you want to save seed from. They flower for quite a long time so perhaps only two types manageable? Do you have a number I mind?
I’m thinking it’s worth monitoring how early all the flowers set on the earliest variety. Then I suppose it’s a question of how late broad beans can successfully be grown. Personally I’ve never tried as I always regard it as an early crop but it would be interesting to experiment with seed saving in mind. .

[Galina]

Later broad beans sowings outside of a greenhouse have always been devastated by blackfly for me. But you will probably have enough seeds for seed saving even so. It helps to 'clean' the tops with a spray of water but it is a lot of work. Ladybirds don't eat them because ants guard the blackfly. I have fleeced a group of broad beans for pure seed and they seem to self pollinate ok, but I understand this is not the best way to do it. Best of all is just to grow the one variety only, but if there are any broad bean growers or field beans in the vicinity if you live in a rural area, you have a problem with this approach.

[Jang]

I don’t think there are any vegetable growers within a mile so lucky in that respect. But field beans are only about 300 metres away.

I can’t see any online reference to hand pollination of broad beans by emasculating etc, and on dissecting a flower to investigate, this looked very difficult - especially for someone who hasn’t even explored a pea flower yet!

Is this possible I wonder and is it ever done by gardeners, or does the anatomy of the flower make it well nigh impossible?

[triffid]

The anatomy of a broad bean flower is very similar to a pea flower - and trust me, peas are not difficult. It may look like a amalgam of inconceivable complexity in there but once you know the basics of what to tug and pinch off you'll be unstoppable.

Here's a good video on crossing peas https://www.youtube.com/watch?v=Pq7-JGRmFBc You can do the same with broad beans.

Incidentally, I did find a video on crossing broad beans. However, I didn't quite understand what the breeder was trying to accomplish, as the female recipient flower was not emasculated and had already shed its pollen on its stigma.

I would speculate that the reason there aren't many references to hand-pollination of broad beans is that commercially it isn't standard practice, and they would just plant rows of the two parents together in an isolated field at let the bees do the rest.