| Автор | LI, XIAOMEI |
| Автор | FENG, YONGSHENG |
| Автор | BOERSMA, LARRY |
| Дата выпуска | 1991 |
| dc.description | Mathematical description of plant processes based on thermodynamic considerations can be used to describe the response of plants to water and temperature stresses. This study was initiated to explore this possibility. Leaf area, shoot dry mass, leaf water potential (ψ1), osmotic potential (π), and the rate of photosynthetic dry mass production (P<sub>t</sub>) of spring wheat seedlings were determined at combinations of five soil water potentials from −0.03 to −0.25 MPa and seven root temperatures from 12 to 32 °C. The relative growth rates of leaf area and shoot dry mass and P<sub>t</sub> were fitted to a mathematical equation derived from thermodynamic considerations. A non-linear least-squares procedure was used with root temperature and ψ<sub>1</sub> as independent variables. These calculations yielded values of activation energy, optimum temperature, and base rates of photosynthesis and plant growth.Activation energies increased with decreasing ψ<sub>1</sub> for growth rates of leaf area and shoot dry mass and for P<sub>t</sub>. Increase of activation energy was greater for the growth rates than for photosynthesis, suggesting that growth was more sensitive to water stress than photosynthesis.The base rate, K<sub>0</sub>, which is the theoretical rate at zero activation energy, for the growth of leaf area and shoot dry mass increased linearly with turgor potential (ψ<sub>p</sub>). However, K<sub>0</sub> was independent of ψ<sub>p</sub> for P<sub>t</sub>. We conclude that the rate of leaf expansion was proportional to ψ<sub>p</sub> and that the proportionality coefficient was affected by temperature and water stresses in a similar manner as P<sub>t</sub> was affected. Our analysis supports the proposition that plant cell extensibility is under metabolic control. |
| Формат | application.pdf |
| Издатель | Oxford University Press |
| Копирайт | © 1991 Annals of Botany Company |
| Тема | Activation energy |
| Тема | water stress |
| Тема | temperature stress |
| Тема | cell extensibility |
| Тема | Articles |
| Название | Activation Energy as a Measure of Plant Response to Temperature and Water Stresses |
| Тип | research-article |
| Electronic ISSN | 1095-8290 |
| Print ISSN | 0305-7364 |
| Журнал | Annals of Botany |
| Том | 68 |
| Первая страница | 151 |
| Последняя страница | 157 |
| Аффилиация | LI XIAOMEI; Department of Crop and Soil Science, Oregon State University |
| Аффилиация | FENG YONGSHENG; Department of Crop and Soil Science, Oregon State University |
| Аффилиация | BOERSMA LARRY; Department of Crop and Soil Science, Oregon State University |
| Выпуск | 2 |
