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Bio-engineers find a way to 'contain' super plants

test culture
Auburn University researchers are creating bio-engineered tobacco plants that are herbicide resistant  

AUBURN, Alabama (CNN) -- Researchers at Auburn University have developed a technique that they say should wilt fears that genetically altered plants will spread their genes around. Based on experiments with tobacco plants, scientists say they can now confine certain implanted characteristics to a single species.

The basic problem that the Auburn scientists were tackling was this: While scientists have already been able to genetically engineer crops that are resistant to weeds and bugs, they want to also make sure that those "super powers" will not be transferred to nearby weeds -- a process that could make the weeds resistant and allow them to spread out of control.

Coming to Terms

Chloroplast: Tiny structures inside plant cells containing the green pigment chlorophyll. Chloroplasts are found in the cells of leaves and in the surface cells of stems. Within the leaf, they occur mostly in those cells near the top of the leaf, where light intensity is greatest.

DNA: A complex two-stranded molecule that contains, in chemical coded form, all the information needed to build, control and maintain a living organism.

It's a fear that has been voiced by critics of bioengineering for years.

Some critics worry that genetically altered plants could transfer their super powers to nearby weeds  

But Auburn says it may have an answer to the problem. University researchers say they have now engineered tobacco plants that are herbicide-resistant and can deliver a deadly bite to bugs that usually devour the plants -- but without passing on those characteristics to other plants.

Dr. Henry Daniell explained the procedure to CNN: the researchers introduce specific DNA into the part of the plant cells called the chloroplast. There, the DNA is released and the genes get integrated into the chloroplast's DNA.  (icon 102K/8 sec. AIFF or WAV sound)

Plant bioengineering
icon 2 min. 15 sec. VXtreme video

The chloroplasts are the key to keeping the tough new genes from spreading to other plants, since the altered genes stay locked up in the chloroplasts and do not get transferred into the pollen.

This means that, even if the genetically engineered plant cross-pollinates with, say, a weed, the genes that convey bug and herbicide resistance will not get passed on to other plants.

In the future, scientists could use DNA-altering processes on cotton plants, making certain cloths fade-resistant  

Once the plant has been made resistant, it's a case of the survival of the fittest: Those that inherit the resistant gene thrive in the laboratory dish and grow into plants and pass the new traits on to the next generation. Those plants that do not accept the genetically altered state die. (icon 102K/9 sec. AIFF or WAV sound)

Tobacco plants are being used because scientists can draw on years of research that has been carried out on the plants in years past. Another key reason is that tobacco plants can be genetically engineered in only three months.

Similar research is already being conducted on peanuts and Chardonnay grapes. Scientists say these techniques also could lead to genetically altered cotton -- and to clothes that won't fade, even after washing and sunlight exposure.

Correspondent Alesia Stanford contributed to this report.


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