favas and seed beetles

[ottawagardener]

Look what I found in a seed package sent to me. These weren't planted out so I hope they didn't some how hop into my garden. They are now double bagged for freezing and then once dead, being throw out. I should have probably frozen the seed when I received it but I've never seen this before:

[ottawagardener]

Oh, I've heard people say that you should wait a year before planting out fava just in case their are seed beetles so that they live and die in their plastic or glass homes (They chew through paper). Apparently, the fava often still germinate but I'm not taking the risk.

[robertb]

I had broad beans once with similar holes, though I didn't see any beetles. I just froze them for a couple of days.

[Joseph Lofthouse]

Last spring I received peas from a collaborator, and when I opened a packet to plant it was filled with those beetles. I planted them anyway, because I already have the beetles in my garden, but because of it I have implemented better seed quarantine procedures... Every seed packet I receive now gets cycled through the freezer upon arrival. And all the seeds I gather get cycled through the freezer as soon as they are dry enough. I see the most insects on incoming corn, legumes, and sunflowers, but I cycle everything through the freezer just to be safe.

I received fabas this fall in the same brand of bag, and ran them through the freezer upon receipt. They have bite marks where the larva entered the seed, but the beetles didn't develop. I think that you would be safe to plant them after cycling them through the freezer.

I am almost paranoid these days about seed quarantines. If I open a jar of seeds and forget to put the lid back on immediately, I cycle it through the freezer. We still have one species of seed eating moth in the house. I think it comes in with groceries or dog food....

[blueadzuki]

Dec 24, 2012 12:36:45 GMT -5 ottawagardener said:

Oh, I've heard people say that you should wait a year before planting out fava just in case their are seed beetles so that they live and die in their plastic or glass homes (They chew through paper). Apparently, the fava often still germinate but I'm not taking the risk.

Yes, they usually will. Ive planted lablab (hyacinth) beans with beetle holes and they grew just fine. Seed beetles are storage insects and per beetle, don't have huge appetites. So long as the holes they make 1. dont let any fungus in and 2. don't cross the embryo (which they rarely do) the seeds are no worse damaged than they would be if you say pierced them to string them (yes I have grown seed like that, until it died about a month ago, I had a Sophora secundifolia seedling going that started it's life with me on a necklace.) the "cookie cutter" holes left are usually not a siginificant loss to the seed, nutition wise (thoughI did once find a case where a seed beetle got itself into a Mucuna venetii (a big hard tropical legume, one of the kinds they sometimes refer to as "hamburger seeds") found it couldn't cut it's way out, and ended up eating the whole seed out from the inside (and those seeds are 3-4 oz apiece)

[12540dumont]

Ahh, the dreaded bean weevil!
Cowpea weevil: Callosobruchus maculatus
Broad bean weevil: Bruchus rufimanus
Bean weevil: Acanthoscelides obtectus

I have them too. I cycle everything through the freezer now too.

Very often, beans are harvested from the garden which look perfectly good. However, there can be bean weevil larvae present inside. These larvae can continue to develop while the beans are in storage, with adults emerging during winter. Never store beans at temperatures 50 degrees and warmer!

Management of Bean Weevils:
1. Sanitation is one of the most practical means of
weevil control. Plow under all field trash and
bean residues in the fall. In spring, do not plant
seed known to be infested with weevils. Avoid
planting from packets or sacks of seed left over
from the previous year, and avoid storage of seed
during the warm, summer months.
2. Keep seed in containers of glass, heavy plastic,
or metal with airtight lids.
3. If infestation of seed is suspected, consider
purchasing a new lot of seed or follow one of the
methods below.

If your seeds are infected, you can do this to make them plantable. Be advised that not every seed will germinate.

a. Heat Treatment. Place beans or peas in a
shallow pan and dry heat at 120°F for 30
minutes or, 145°F for 15 minutes. Be sure
beans are left long enough for the heat to
penetrate to the center of each seed for the
required period of time to kill the larva.
b. Cold Treatment. All stages of bean wee-
vils are killed by super-cooling in a deep
freeze at 0°F for 4 days, or placing beans in
cold storage at 32°F for 58 days. However,
both of these methods may slightly reduce
seed germination. Storage in a refrigerator,
which is usually about 40°F, stops insect
development but does not kill the insects.
4. In general, insecticides are not warranted for
bean weevil control in the garden. The use of
insecticides indoors or around food supplies is
discouraged.

Ottawa, if those came from me, throw them out and I'll send you a new batch. Just let me know. I have stored last year's favas in the freezer as I know weevils are now present in my garden. I now routinely store all peas, beans, corn in the freezer.

[petitvilaincanard]

I have 50%+ infested bb's.
I don't do anything about it .
Germination of my beans is good,but if you eat dry beans it can make them less appetitive.
But I eat them mostly green,so this is not really a problem.

The beasties lay the eggs somewhere in the green stage,but they don't spread in dry beans.
Sometimes I,ve a low degree of infested beans.
If I want to find out what factors reduce infection,I need to have permanent pressure of these beetles.
If there are genetic factors that reduce infestation,I'm in heaven because selection for non infested beans is easy.

So,if you don't care about them,life is easier and the fava's can do well