Creating loosely hybrid grain corn (long post warning)

I imagine most of us on here are at least somewhat familiar with open pollinated corn and have read a bit about some inherited genetic traits, maybe the xenia effect, or how hybrids are made, etc.

In the interest of combining a few breeding project goals in the same plot, I'd like to run my plans by you guys to see if I'm on the right track. Feedback or other ideas welcome.

Background: I have grown out 3 strains of 100% white dent corn over the past 2 years. The first year was Hickory King White Dent. I received about half of my seed from a reputable business & the other half in trade. I planted all seeds together in the same plot. They grew pretty well for me with most being 8-row, and a few 10 or 12 row cobs. Some even gave 2nd ears. Over time, I've shared or traded most of the seed I'd saved & only have a small amount left.

Last year, I grew out the 3rd strain of white dent that I'd received in trade as well. This one was labeled "Mosbic's Prolific" on the envelope, which after researching the best I could, I suspect it could be Moseby's or Mosby's Prolific, but what's in a name... anyway, I planted it, & it did even better than the previous year's Hickory King! Thicker stalks, full ears,  & generally leafier, which I suspect is an attribute of old timey silage types for fodder.

Goal #1) Since I am very satisfied with these strains, & like the ability to easily tell if any commercial yellow pollen landed on a silk here or there, I want to keep growing them. The problem is, I didn't start out with the minimum recommended 200+ plants of either variety, so it wouldn't be long before inbreeding took its toll. That's why I'm wanting to effectively broaden my white corn gene pool by combining these 3 original source strains via natural open pollination methods. I think they are compatible in many ways, & plan to continue crossing in different 100% white heirloom strains every 3rd year or so. Eventually, developing something new and relevant from many historically significant varieties.

Goal #2) I read somewhere that blue corn landraces are easy to make. While I'm skeptical, I assume they meant easy to select for color alone, which seems simple until you look closely at all the variations that can occur. So, what did I do? I manually sorted through my flint/ flour/ dent seeds one kernel at a time until I had a jar of mostly blue indiginous corn to start my blue mix. At face value, one would think that if you planted all these seeds together you would have a high probability of getting blue corn as the predominate outcome. However, I think there may be other ways to filter out undesired traits.

1. If I'm remembering correctly, any pollen from a plant with other than white kernels that lands on a silk of a white kerneled plant, would exhibit a developed kernel with a color other than white, indicating a hybrid cross in that single seed. If I planted the above white corn mix in double rows alternating rows with the selected blue corn mix, and detassled the white corn plants, then, any kernel that developed on the white plants' cob would be a hybrid fathered by one of the blue seeded plants, but not necessarily giving a blue seed in the F1 since the blue plant backgrounds are wildly diverse. That's a good way to get clear hybrids, but not if you want to see which traits the mother contributed to the kernel in this generation. I think I might want to try the opposite way.

In the same planting scenario as above, if I were to detassle the plants that came from blue seed & leave the white corn to freely pollinate both the white corn plants and the plants that came from blue seed. Then, wouldn't the mother plants that came from blue seed be the most reliable examples of what genetics are dominant in each mother plant since more or less, the white seeded pollen donors are about equal in contribution? In other words, since I know what I'm going to get by crossing the white dents with each other (more white dents), wouldn't being able to view each mother plant that came from blue seed be a better way to determine that plant's potential with regard to row count, kernel color, kernel size, ear length, aerial roots, plant health, etc.?

I hope I explained this well enough to understand, but if not, I can try again.

Hi,
Interesting challenges, and questions.
Regarding your white corn population: Yes, theoretically it is possible to see pollination from other, commercial yellow (gmo…) corn. The only exception is if the yellow corn itself is a hybrid between a yellow and a white corn, then not all seeds would be coloured. This could for example happen if a neighbour replants the own seeds year after year instead of buying commercial seeds. If you have a sufficient population and diversity, you won't need to bring in new varieties every few years, you can let the population evolve on your land.

Regarding your blue corn questions, I am not sure I got them right. However, a quick internet search showed that the blue corn colour can be either in the pericarp (maternal seed coat) or the aleurone layer (derived from fertilization), and that it is based on several dominant genes, (at least 2) which must both be present to have a blue corn.

Therefore, if you plant your blue corn together, it will have a higher likelihood of producing blue cobs. To create a fully blue population without any other colour, the process depends on the genetics, if it is a blue pericarp or blue aleurone corn that you want, and have genetics for. If it is a blue aleurone, you increase the speed of selection if after a year or two you only take cobs which are entirely blue, instead of blue kernels in multi-colour cobs. As you see the colour only after pollination, you could do manual crosses between all the plants, always 2 plants pollinating each other, and then take only the cobs of couples which are entirely blue. Would require a lot of work, but then you have a start without other colours.

As for which one to detassel (blue or white) to create your population: It depends on your priority. If you want to keep your white population and have an experimental blue population, then you can detassel the blue population. This sets you back one year in the blue population, as then you have less blue in there, but you keep your white one. Detasseling the white one means that you lose your white population, setting you back there.

Unfortunately, because of where I live, I think all farmers grow gmo yellow corn as far as the eye can see.  The good news is, you can avoid cross pollination by growing corn every other year during their soybean rotation or using planting times to your advantage.

As far as the farmers using saved seed, I don't think they can legally replant gmo seed, but if they did save hybrid seed with one of the parents being white & the other yellow, wouldn't the successive generations have the occasional white kernel from double recessive genes? Everything here is visibly yellow, but I can't say for sure about anything else.

I intend to continue improving my white corn mix either way, as I already have several more varieties to incorporate after I grow each of them out alone for a season first. That's why the ~3 year cycle, to give me a chance to grow out 2 new white varieties before crossing them into the mix, if I like them.

The blue corn mix is honestly just a project for fun to maybe learn something about breeding in the process.  I know that there are some really good seeds in the mix that I'd like to see how they do when pollinated by the white corn.  Every kernel in this mix was hand shelled off the cob by me, so I know that this blue seed mix will have a very wide range of phenotypes. Some may not be what I want to carry forward, but the ones that are should be pretty interesting as F1 hybrids.

Or, I could be overthinking things with this blue mix, but the idea was that if I controlled the 50% that I'm satisfied with (that is the white corn), then only the blue mother's traits would be the variable I'd need to determine. Since the blue mothers are not outcrossing, I can choose with reasonable certainty which ones I want to carry forward.  I imagine there will be recessive other color genes and double white that will show up in future generations, but I'd think that could be largely weeded out over time. I imagine that maybe blue strains such as Hopi blue, Cherokee white eagle, or any of the blue Pueblo landrace types were most likely blue seed that were saved and grown together over and over until the blue dominated. Even today, occasional other colors appear in a blue population, usually red from what I've seen. I'm just curious natured & have some seed to play with. Maybe something good will come from it, maybe I'll learn something.

I am curious about something else though that may be along a similar vein. I recall reading that Joseph Lofthouse attempted an all white corn landrace, but he could never get it to stay white. Does anyone have more information about this? Thanks.