Aspen Bibliography

Title

Genetic engineering for air-pollutant resistance in hybrid aspen

Document Type

Article

Journal/Book Title/Conference

Micropropagation, genetic engineering, and molecular biology of Populus, Fort Collins, Colo. : U.S. Dept. of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station

First Page

187

Last Page

191

Publication Date

1997

Abstract

Preservation of the natural environment, a growing worldwide concern, is being approached in various ways. Forests are useful because they continuously eliminate air pollutants while remediating and preserving the natural environment. Forest trees have a high capacity to absorb air pollutants and detoxify toxic substances produced by air pollution, but they do not adequately resist harmful air pollutants and other environmental stresses. An effec- tive way to preserve the natural environment is to improve the resistance of forest trees to air pollutants and other environmental stresses.

Damage to plant cells ~aused by environmental stresses, including herbicide exposure, high intensity light with low temperature, or air pollutants such as ozone and sulfur dioxide, is related to the over production of active oxygen in the cells. Active oxygen, such as singlet oxygen {10 ),

2 superoxide (0;), and hydrogen peroxide (H 0 ), are the

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by-products of many biological oxidations. For example, the electron transport chain of mitochondria and chloro- plasts is a well-documented source of active oxygen. In plant cells, detoxification systems for active oxygen have evolved to facilitate immediate removal of active oxygen. However, under stressful situations, the equilibrium be- tween the oxidative and antioxidative capacity can change within the plant cells, so that over production of active oxygen is induced. As the oxygen detoxification system of higher plants has become better understood, we have at- tempted to improve the detoxification system by using genetic engineering to increase resistance to environmen- tal stress.