Photosynthesis and Water Relations in Tomato Plants Cultivated Long-Term in Media Containing (+)-Usnic Acid |
| |
Authors: | E. Latkowska Z. Lechowski J. Bialczyk J. Pilarski |
| |
Affiliation: | (1) Department of Plant Physiology and Development, Jagiellonian University, Gronostajowa 7, 30-387 Cracow, Poland;(2) Department of Plant Physiology, Swietokrzyska Academy, Swietokrzyska 15, 24-406 Kielce, Poland;(3) Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 2, 30-239 Cracow, Poland |
| |
Abstract: | The influence of (+)-usnic acid on rates of gas exchange (photosynthesis, respiration, and transpiration) in long-term cultivation of tomato plants was studied. The effect was dose-dependent. Plants grown in media containing the maximum concentration of (+)-usnic acid (30 μM) had photosynthetic and respiration rates reduced by 41% and 80%, respectively. The effect on photosynthesis rate may be the result of a multidirectional effect at various stages of this process, which at the highest usnic acid concentration underwent reduction: content of chlorophylls by 30%, carotenoids by 35%, and Hill reaction activity by 75%. Usnic acid also raises the susceptibility of chlorophyll to photodegradation. Under some conditions, transpiration was reduced by 2.1-fold in light and 3.7-fold in dark. This result was correlated with (1) an increase in the diffusive resistance of the stomata (3.1-fold in upper and 1.5-fold in lower surface of leaf), (2) a reduction of stomata density (by 60% on upper and 40% on lower surface), and (3) a 12.3-fold decrease in root hydraulic conductance. |
| |
Keywords: | Allelochemicals Photosynthesis Tomato Transpiration (+)-usnic acid |
本文献已被 PubMed SpringerLink 等数据库收录! |
|