Anti-oxidative and anti-senescence effects of the strobilurin pyraclostrobin in plants: A new strategy to cope with environmental stress in cereals

摘要

In addition to its broad spectrum fungicidal activity, the strobilurin pyraclostrobin had positive effects on the crop yield in the absence of pathogen challenge. This physiological effect on the plants was especially apparent under conditions of environmental stress. We have observed that pyraclostrobin prevented both symptom development and yield reduction by physiological leaf spot in barley. Foliar application of pyraclostrobin reduced the production of reactive oxygen intermediates in barley leaf tissues by more than 50% and activated the plant antioxidative system. In addition, pyraclostrobin treatment prevented the release of stress-induced ethylene and premature senescence. Since the physiological leaf spot disease and other environmental stresses are caused by changes in the genetic and metabolic regulation of reactive oxygen intermediates resulting in membrane-leakage, cell death or premature senescence, we postulate that the anti-oxidative and anti-senescence effects of pyraclostrobin are responsible for its ability to improve stress tolerance in plants.