Decades ago, researchers wanted to develop a strain of wheat that could be harvested with machinery. This would allow vast fields to be harvested faster with less labor cost. They planted millions of wheat plants.... then one season they found a single individual whose seed pods did not shatter and scatter its seeds on the ground when harvested. All strains of wheat grown today are descended from that one individual plant.

Decades ago, researchers in Argentina discovered by accident an orange tree whose fruit had no seeds. All seedless orange trees grown today are mature clippings from that original tree.

Today, researchers at the University of Florida are testing seed for growth under hypoxia and vacuum conditions, such as those found in space.

http://www.ncsu.edu/kenan/ncsi/Docs/Presentations/Ferl.ppt