Why commercial exploitation of heterosis is not feasible in wheat?

Answer 1

For a plant to express heterosis, it must be a hybrid, or the offspring of two separate and genetically distinct parents. Producing corn hybrids, for example, is reasonably easy, since all that must be done to produce the seed is to plant both parents throughout the field, then remove all the tassels, or pollen-producing parts, of all the designated "female" plants. By then harvesting only the "female" plants, only true hybrid seed will be the product.

Wheat, though, is a very different matter, since the pollen-producing parts are on the same part of the plant with the ovaries. While physical removal of the pollen can be accomplished, it is extremely difficult, especially in any large quantity. It might be possible to produce "male-sterile" parents, such as are used in hybrid onion and carrot seed production, but the economic value of the wheat would not justify such expense.