I’ve been thinking about the fact that many grains (including wheat, rice, and barley) seem to have low outcrossing rates; in that, they are rather like tomatoes or common beans, rather than like corn.
Why would a wind-pollenated grass develop self-pollinating characteristics? That doesn’t seem to make sense.
And, would something like the work @Joseph_Lofthouse is doing to develop outbreeding tomatoes be useful? Does the inbreeding of these grains lead to weaker plants? Corn suffers terribly from inbreeding depression; are F1 wheat or barley plants more vigorous?
This is something I’ve wondered as well. I was considering a barley landrace but read that pollination occurs even before flowers emerge. Natural outcrossing would be negligible.
Our agriculture system purposefully selects for inbreeding crops. By doing so, it also selects for inbreeding flower types. Charles Darwin noticed that naturally occurring hybrids produce plants that are somewhat more promiscuous than their parents.
Growing mixed populations, closely spaced, will tend to select for more promiscuous flowering types.