| Autor: |
Anev, S., Ivanova, A., Tzvetkova, N., Panayotov, M., Yurukov, S. |
| Předmět: |
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| Zdroj: |
Genetics & Plant Physiology; 2016, Vol. 6 Issue 1/2, p43-53, 11p |
| Abstrakt: |
Stomata have a key role in the balance of gas exchange parameters. Stomatal closure limits transpiration under conditions of water deficit. It also suppresses photosynthesis due to limited CO2-uptake. We examined the levels of stomatal control on the photosynthesis of Pinus mugo Turra, Pinus peuce Griseb. and Pinus heldreichii Christ. saplings during a two-year drought experiment. Plants were exposed to three different irrigation regimes (according to the annual course of precipitation): typical for the natural area of the species; for years with extremely dry periods during July as well as for years with drought during August. A species specific stomatal control on the rate of photosynthesis (An) under different irrigation regimes was observed. P. mugo saplings showed great resistance to drought, they kept similar An under the different irrigation schemes and increased intrinsic water-use efficiency (iWUE) under drought conditions. P. peuce saplings had reduced stomatal control on An, especially in the situation with late summer drought and unchanged iWUE. P. heldreichii saplings had very low An and stomatal conductance under all irrigation schemes accompanied by an increase in iWUE during early summer drought and a decrease in late summer drought. The relationships between photosynthesis and stomatal conductance under the three irrigation schemes were close to linear - photosynthesis did not reach asymptote in this species. These differences in the reaction of photosynthesis to stomatal conductance could be used as a good indicator for the adaptability of the studied species to summer drought. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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