The Role of Light and Oxygen in the Action of the Photosynthetic Inhibitor Herbicide Monuron
نویسندگان
چکیده
Herbicidal Action of Monuron, Light, Oxygen, Singlet Oxygen, Plant Pigments Monuron treatment of detached flax cotyledons caused a rapid inhibition of C 02 fixation in darkness and light. Chlorophyll breakdown was promoted by increased light intensity. Ethane generation, an indicator of membrane damage, increased as the chlorophyll level decreased. The carotene pigments were destroyed more rapidly than the xanthophylls and chlorophylls. Treatment of cotyledons with monuron in the absence of oxygen almost prevented carotenoid and chlorophyll loss. The addition of the singlet oxygen quencher DABCO delayed chlorophyll breakdown. The results are discussed in relation to a role for singlet oxygen in the herbicidal action of monuron.
منابع مشابه
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