You won't notice any difference in the seed at all--it's being developed by the mother plant and only contains the germ plasm from both parents down in the embryo.

The daughter plant will differ, of course, but the seed looks the same as any other seed from that plant.

While I can't think of any exceptions to that rule, it wouldn't surprise me to find out there are some. :) Regardless, no matter how wild the crossbreed, I've never been able to identify that from developing seed or fruit or anything else.

Hi and thanks for responding. I found this article which seems to be saying that in their experiment they found that there were visible differences in the corn seed in the first year, but perhaps I've read it wrong. Any thoughts?

Here is a link that might be useful: Article on corn seed saving

Here's an article from an extension service that seems to confirm.

"If the part of the plant you eat is the seed, then its characteristics are determined by both parents. An example is corn which is subject to visible crossâÂÂpollination effects because the corn kernels are actually the seeds of the corn plant. Therefore, a cross between field corn and sweet corn would give tougher, less sweet ears."

Here is a link that might be useful: Vegetable Cross Pollination

You might be able to in the case of corn, although I've never heard of anybody managing.

In most of my cases, eggplant, and flowers, crossbreeds are invisible. Even if my 12" dahlia got cross-pollinated by my 48" dahlia, the seeds are identical. The genetic differences will only show if I plant the seed--which is why I go back to the seed company every year for the smaller dahlia (and save tubers of the large ones).

I've occasionally gotten a species reversion or crossbreed on the eggplant. But the seed looked the same as any other.

Corn definitely shows cross pollination in the year of growing but nothing else can. Bean seeds will not show anything different. The DNA inside will just grow into something different next year, but bean cross pollination is rare anyway. We are talking 1%.

Yes corn will show cross pollination in the first year. For example, if you have a blue corn plant that gets pollinated by a yellow corn plant, you will see yellow kernals when you pick and shuck this years harvest.

Common beans (phaseolus vulgaris), as it was mentioned, very rarely cross in the home garden setting. The stigma and anthers touch within the flower so that when pollen is shed, it is immediately deposited within the same flower, usually before it even fully opens. Beans lack the insect attractants present in other flowers and are thus not favored or frequented by them. As to whether you will be able to see any difference in the dried bean seed in the same year, I have never heard of that being a trait in beans.

Thanks everyone.

Following up on this much later, I asked this question to Lynne Bellemare who works for Seeds of Diversity here in Canada (and also grows a lot of beans!) and she told me that the ability to see crossing in corn seeds is unique to that species because of something called the "Xenia effect". I've just looked it up and found this nugget of wisdom on Wikipedia:

The endosperm
tissue, which makes up most of the bulk of a maize seed, is not
produced by the mother plant, but is the product of fertilization, and
genetic factors carried by the pollen affect its colour.

https://en.wikipedia.org/wiki/Xenia_(plants)

In other words, corn is unique because each kernel is a fruit. The pollination is different than other veggies.