With this genetic modification, the trees were able to produce an insecticidal protein that helped protect against insect attack. This method has proven effective as a pest control measure in other crop species such as corn and soybeans, resulting in substantial reductions in pesticide use and a decrease in crop losses.
"Insect attack not only can kill a tree, it can make the trees more vulnerable to other health problems," said Amy Klocko, an OSU faculty research associate. "In a really bad year of insect attack you can lose an entire plantation."
Hybrid poplar trees, which are usually grown in dense rows on flat land almost like a food crop, are especially vulnerable to insect epidemics, the researchers said. Manual application of pesticides is expensive and targets a wide range of insects, rather than only the insects that are attacking the trees.
A number of the GMO trees in this study also had significantly improved growth characteristics, the researchers found. Compared to the controls, the transgenic trees grew an average of 13 percent larger after two growing seasons in the field, and in the best case, 23 percent larger.
Some of the work also used a drought-tolerant poplar clone, another advantage in what may be a warmer and drier future climate. The research was supported by the Tree Biosafety and Genomics Research Cooperative at OSU.
Annual crops such as cotton and corn already are routinely grown as GMO products with insect resistance genes. Trees, however, have to grow and live for years before harvest and are subjected to multiple generations of insect pest attacks. That's why engineered insect protection may offer even greater commercial value, and why extended tests were necessary to demonstrate that the resistance genes would still be expressed more than a
|Contact: Steve Strauss|
Oregon State University