The seeds do not naturally disarticulate from the ear. They remain on so that the seeds can be harvested by us at any time. The male part of the species at the top of the vegetative stalk promotes rapid pollination. The production of female flowers also occurs near the top so that mechanical harvesters will cut below the parts and ensure collection of the seed. The highly inbred nature of corn is good for seed production but not good to maintain some level of variation.
Corn is susceptible to fungal and bacterial disease.
They do not have genes resistant to these pathogens. This allows then for increasing the genetic variation of the corn and allowing it to become better adapted as a human-directed species. You cannot do much of this intercrossing unless you know what the chromosome number of the parents ought to be. This is basically an introduction to my work with the greenhouse, as well as my overall research thrust. This information is going to be included in the Manual of the Virginia Flora, which is the major outgrowth of the Virginia Flora Committee, of which I am a member.