Thermal dependence of enzyme function and inhibition; implications for, herbicide efficacy and tolerance
- 6 January 2004
- journal article
- Published by Wiley in Physiologia Plantarum
- Vol. 120 (2), 187-195
- https://doi.org/10.1111/j.0031-9317.2004.0255.x
Abstract
Environmental temperature is a critical factor in the lives of almost all organisms. Plants experience periods of thermal stress related to seasonal patterns of temperature and periodic water deficits. Within the range of non-lethal temperatures, there are a number of thermal effects on metabolism that are a result of the thermal dependence of enzymes. The thermal dependence of enzyme kinetic parameters was used to predict that the efficacy of the herbicide pyrithiobac on Palmer amaranth would be reduced at temperatures outside a 20-34 degrees C thermal application range. This prediction is validated in a controlled environment study described in this paper. Palmer amaranth was grown for 16 days in growth chambers with 34/18 degrees C day/night temperature regime. Pyrithiobac was applied to plants at 18, 27 or 40 degrees C. After 1 h at the application temperatures the plants were returned to the 34/18 degrees C regime for 14 days and post-application biomass accumulation (efficacy) was determined. Dry weight accumulation, as a percentage of untreated controls, was 25, 2.5 and 70% for 18, 27 and 40 degrees C application temperatures. Pyrithiobac efficacy was highest for the application within the thermal application range and significantly reduced at temperatures above and below. The validation of the earlier prediction suggests that temperature-related kinetic limitations on herbicide efficacy may also occur in plants with bioengineered herbicide resistance based on herbicide metabolism. The theoretical aspects of such thermal limitations on herbicide resistance mechanisms are discussed.Keywords
This publication has 24 references indexed in Scilit:
- A Mechanism for Stabilization of Membranes at Low Temperatures by an Antifreeze ProteinBiophysical Journal, 2002
- A thermal application range for postemergence pyrithiobac applicationsWeed Science, 2001
- The development of herbicide-tolerant transgenic cropsField Crops Research, 1996
- Evolution, structure and function of the small heat shock proteins in plantsJournal of Experimental Botany, 1996
- Thermal Dependence of Glutathione Reductase; Thermal Limitations on Antioxidant Protection in PlantsCrop Science, 1994
- Thermal Dependence of the Apparent Km of Glutathione Reductases from Three Plant SpeciesPlant Physiology, 1990
- The Development of Herbicide Resistant CropsAnnual Review of Plant Physiology and Plant Molecular Biology, 1989
- Herbicide Resistance in Transgenic Plants Expressing a Bacterial Detoxification GeneScience, 1988
- Expression in plants of a mutant aroA gene from Salmonella typhimurium confers tolerance to glyphosateNature, 1985
- Temperature Adaptation of Enzymes: Biological Optimization Through Structure-Function CompromisesAnnual Review of Ecology and Systematics, 1978