chlorophyll-a and chlorimuron-ethyl

It was observed in this work that joint effects of chlorimuron-ethyl and copper on chlorophyll content, the peroxidases (POD) activity, superoxide dismutases (SOD) activity and soluble protein content in leaves and roots of wheat were markedly significant. The chlorophyll content and the SOD activity in wheat under joint stress of chlorimuron-ethyl and copper were obviously higher than that under single stress of chlorimuron-ethyl. However, joint effect of chlorimuron-ethyl and copper on the decrease of soluble protein content in roots was more serious than that under single stress of chlorimuron-ethyl. The effect of copper dominated the change of POD activity and soluble content in leaves and roots of wheat under joint stress of chlorimuron-ethyl and copper. It was suggested that the change of enzyme activity was related to the change of soluble protein content in roots under single and joint stress of chlorimuron-ethyl and copper.

Topics: Chlorophyll; Copper; Drug Synergism; Peroxidases; Plant Leaves; Plant Proteins; Plant Roots; Pyrimidines; Sulfonylurea Compounds; Superoxide Dismutase; Triticum

Changes in the activity of antioxidant enzymes including peroxidases (POD) and superoxide dismutases (SOD) and in the contents of chlorophyll (CHL), malondialdehyde (MDA), and soluble proteins (SP) in wheat (Triticum aestivum) under the stress of chlorimuron-ethyl in soil were examined. Chlorimuron-ethyl induced oxidative stress that was indicated by elevated MDA content in leaves and roots after a 1-day exposure. The 300-microg/kg chlorimuron-ethyl treatment caused significant damage to CHL accumulation. The higher POD activity in roots than in leaves may be the result of the tissue-specific gene expression in the roots. Our data could suggest that the plant has the capacity to counteract the oxidative stress caused by 5-150 microg/kg chlorimuron-ethyl exposure at the first stage, but the capacity would be lost with exposure time. It is indicated that the increase of POD activity in the leaves may have been caused by H(2)O(2) produced from sources other than SOD. The damage to the antioxidative defensive systems in plants is affected by the concentration of chlorimuron-ethyl and exposure time, and the defensive effect of antioxidative enzymes is completely lost with prolonged exposure. When treated with 300 microg/kg of chlorimuron-ethyl, a significant decrease of SP content and SOD activity in the leaves and roots indicated that the decrease of SP content and the activity of SOD can be considered biomarkers of the serious stress of chlorimuron-ethyl in soil. The increase of SP content in leaves after 3-4 days of exposure to 5-150 microg/kg chlorimuron-ethyl suggests that the enhanced POD activity was due to true induction of de novo synthesis rather than reactivation of preexisting apoprotein. It can also be concluded that dose-response relationships exist only between the SP content in roots and leaves and the concentration of chlorimuron-ethyl.

Topics: Chlorophyll; Herbicides; Malondialdehyde; Peroxidases; Plant Leaves; Plant Roots; Pyrimidines; Soil Pollutants; Sulfonylurea Compounds; Superoxide Dismutase; Triticum

Biochemical responses to joint stress of chlorimuron-ethyl and cadmium (Cd) in wheat Triticum aestivum were examined. The joint action of chlorimuron-ethyl and Cd weakened the inhibition of Cd or chlorimuron-ethyl on the formation of chlorophyll. It was deduced that wheat plants had the capability to protect themselves by increasing the activity of the antioxidant enzyme peroxidase (POD) with the exposure time. The joint effect of chlorimuron-ethyl and Cd on the superoxide dismutase (SOD) activity in leaves was additive, while the joint effect on the SOD activity in roots was determined by the interaction of chlorimuron-ethyl and Cd in wheat. It was also concluded that the change of malondialdehyde (MDA) content in wheat might not be a good biomarker in the oxidative damage by chlorimuron-ethyl, while a decrease in the soluble protein content and POD activity in roots could be considered as a biomarker in the damage of wheat by chlorimuron-ethyl and Cd.

Topics: Antioxidants; Cadmium; Chlorophyll; Environmental Pollutants; Lipid Peroxidation; Malondialdehyde; Peroxidase; Plant Leaves; Plant Proteins; Plant Roots; Pyrimidines; Sulfonylurea Compounds; Superoxide Dismutase; Toxicity Tests; Triticum