After more than 20 years of theorizing about it, scientists have tweaked a hybrid variety of rice so that some of the plants produce cloned seeds. No plant sex necessary. The feat, described December 12 in Nature, is encouraging for efforts to feed an increasingly crowded world.
Crossing two good varieties of grain can make one fabulous one, combining the best versions of genes to give crops desirable traits such as higher yields. But such hybrid grain marvels often don’t pass along those coveted genetic qualities to all seeds during reproduction. So farmers who want consistently higher yields have to pay for new hybrid seeds every year. This new lab version of hybrid rice would preserve those qualities through self-cloning, says study coauthor Venkatesan Sundaresan, a plant geneticist at the University of California, Davis.
Though 400 kinds of plants, including some blackberries and citruses, have developed self-cloning seeds naturally, re-creating those pathways in crop plants has “been harder than anyone expected,” Sundaresan says. He and his colleagues got the idea for the new research while studying “how a fertilized egg becomes a zygote, this magical cell that regenerates an entire organism,” as Sundaresan puts it.
The researchers discovered that modifying two sets of genes caused the japonica rice hybrid called Kitaake to clone its own seeds. Read more