|MadSci Network: Agricultural Sciences|
I am going to point you to some resources written by the experts...
The Ontario Corn Producers Association
As you can see from these, corn is monoecious. That is, the stamens and pistils are found in two different "flowers".
To prevent a plant from self pollinating, simply remove the source of the pollen, the tassel. This is called, appropertly enough, detasseling! The pollen from another plant can then be used pollenate the silks.
As far as indoor or outdoor, I would suggest growing corn outdoors. In my experience, it dosen't do extreamly well in a greenhouse. It will be necessary to isolate your project from surrounding corn fields and your other crosses. Plastic bags can be placed over the silks to prevent accidental pollination.
Hope this helps!
Department of Horticutlure
Penn State University
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