Xu S.,Lanzhou University |
Lin D.,Zhuanglang Agro Technology Extension Center |
Sun H.,Lanzhou University |
Yang X.,Academy of Gansu Agricultural science |
Zhang X.,Lanzhou University
Acta Physiologiae Plantarum | Year: 2015
As an essential micronutrient, iron (Fe) is directly involved in several fundamental processes in the photosynthetic cells. However, it is not clear if photosynthetic traits affected by high ferrous level are associated with changes in fatty acid composition in chloroplast membranes. To accomplish this, the effects of excess Fe2+ on the fatty acid composition and the fluidity properties of the chloroplast membrane, photosynthesis rate and the chlorophyll fluorescence were investigated in pea (Pisum sativum L.) seedlings grown hydroponically in nutrient solutions with 100, 200, 400 and 600 µM Fe2+ supplied as FeSO4. Increased fluidity of the chloroplast membranes was found under higher Fe2+ treatments, and this might be attributed to the increase in relative content of unsaturated fatty acids (USFA). Excess Fe2+ decreased the chlorophyll content and the electron transport rate, deactivated reaction center of photosystem II, and declined plant net photosynthetic rate. Finally, the reduced plant dry weight was observed. The results indicate that the effects of excess Fe on photosynthesis and fluidity of chloroplast membrane depend on the stress strength and duration, and the increased fluidity of chloroplast membrane may be critical in maintenance of cellular integrity under excess but not lethiferous Fe2+ treatment. © 2015, Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków.