PHYSIOLOGICAL RESPONSE OF FOUR SOUTHERN HERBACEOUS PLANTS TO ALUMINIUM STRESS

Authors Liu Peng; Yang Y S; Xu Gendi; Guo Shuiliang; Wang Min

Journal Acta Phytoecologica Sinica , 2005,4:29

Abstract The aim of this study was to determine the effects of Al stress on the physiological responses of four herbaceous plants and to analyze the differences in their physiological responses. Four southern herbaceous plants, Pharbkis nil, Cassia occidenllis, Echinochloa colonum and Aeschynomene indica , which are distributed in the red soils of South China, were used to study the seed germination, chlorophyll content, levels of pro-line, malondialdehyde (MDA), membrane penneability (MP) and soluble sugar (SS), and activities of perox-ides (POD) and catalase (CAT) in their leaves under five Al treatments (0, 80, 400, 2 000, 10 000 mg-IT1) with the sand culture method. The results showed significant effects of Al on the physiological characteristics of these four herbaceous plant species. The seeds of all four species could not germinate at the 10 000 mg·L-1 Al3+ treatment and were disadvantageous to growth under the 2 000 mg·L-1 Al3+ treatment. When compared to the control, the 2 000 mg·L-1 Al3+ treatment significantly {p <0.05) reduced the contents of chlorophyll a and chlorophyll a+ b (p < 0.05) , promoted levels of MDA and MP (p < 0.05) , very significantly increased the content of proline (p<0.01) and depressed activities of POD ond CAT (p < 0.01), hi the 80 mg·L-1 and 400 mg·L-1 Al3 + treatments, levels of MDA and MP in P. nil and A . indica leaves decreased, and the activities of POD and CAT increased compared to the control, but variations in C. occidentlis leaves showed an opposite response. Changes in E. colonum leaves were similar to P, nil and A. indica under 80 mg·L-1 but opposite to those under the 400 mg·L-1. These species maintained higher activities of POD and CAT, higher contents of chlorophyll and proline, and lower contents of MDA and MP, thus improving their tolerance to Al stress under low and medium Al treatments.

Species covered 合萌 Aeschynomene indica 光头稗 Echinochloa colonum