Plants cloned as seeds

February 17, 2011

Plants have for the first time been cloned as seeds. The research by aUC Davis plant scientists and their international collaborators, published Feb. 18 in the journal Science, is a major step towards making hybrid crop plants that can retain favorable traits from generation to generation.

Most successful crop varieties are hybrids, said Simon Chan, assistant professor of at UC Davis and an author of the paper. But when hybrids go through sexual reproduction, their traits, such as fruit size or frost resistance, get scrambled and may be lost.

"We're trying to make a hybrid that breeds true," Chan said, so that plants grown from the seed would be genetically identical to one parent.

Some plants, especially fruit trees, can be cloned from cuttings, but this approach is impractical for most crops. Other plants, especially weeds such as hawkweed and dandelions, can produce true seeds that are clones of themselves without -- a still poorly understood process called apomixis.

The new discovery gets to the same result as apomixis, although by a different route, Chan said.

Normally, eggs and sperm are haploid -- they have half the number of chromosomes of the parent. The fertilized egg and the adult plant it grows into are diploid -- containing a full complement of chromosomes, half contributed by each parent.

Chan and his colleagues focused their work on the laboratory , which has certain that allow it to produce diploid eggs without sexual recombination. These eggs have the same genes and number of chromosomes as their parents. But those eggs cannot be grown into adult plants without fertilization by sperm, which adds another parent's set of chromosomes.

Last year, Chan and UC Davis postdoctoral researcher Maruthachalam Ravi showed that they could breed haploid Arabidopsis plants that carried chromosomes from only one parent. They introduced a genetic change so that after the eggs were fertilized, the chromosomes from one of the parents were eliminated. Such haploid plants would reduce the time needed to breed new varieties.

In the new study, Chan's lab, with colleagues from India and France, crossed these Arabidopsis plants programmed to eliminate a parent's genes with either of two mutants that can produce diploid eggs.

The result? In about one-third of the seeds produced, the diploid were successfully fertilized, then the from one parent were eliminated, leaving a diploid seed that was a clone of one of its parents.

Ravi described the result as a step on the way towards artificial apomixis. The team hopes to produce , such as lettuce and tomato, that can fertilize themselves and produce clonal seeds. Applications for provisional patents on the work have been filed.

Explore further: Studying How Modified Genes Escape Into Nature

Related Stories

Studying How Modified Genes Escape Into Nature

February 5, 2007

A University of Arkansas researcher and her colleagues are developing a way to examine how the genomes rearrange themselves during hybridization to better pinpoint how genetically modified organisms may behave when they cross ...

Is this the beginning of the end of plant breeding?

June 9, 2009

No human is a clone of their parents but the same cannot be said for other living things. While your DNA is a combination of half your mother and half your father, other species do things differently. The advantage of clonal ...

Cloning plants from seeds

December 15, 2009

( -- Wageningen geneticists (The Netherlands) are developing a method to replicate the parents of a chosen plant. Known as 'reverse breeding', this will have a big impact for the breeding industry.

Chance Observation Leads to Plant Breeding Breakthrough

March 24, 2010

( -- A reliable method for producing plants that carry genetic material from only one of their parents has been discovered by plant biologists at UC Davis. The technique, to be published March 25 in the journal ...

Recommended for you

A common mechanism for human and bird sound production

November 27, 2015

When birds and humans sing it sounds completely different, but now new research reported in the journal Nature Communications shows that the very same physical mechanisms are at play when a bird sings and a human speaks.

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

1 / 5 (1) Feb 18, 2011
Can similar ideas work in animals?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.