The Physiological Adaptation Of Brugiera Sexangula And Kadelia Candel Seedlings To AlCl₃

Based on plant physiological and chemistrical analysis and ICP-MS techniques, the research on the effect of AlCl₃ treatment on the physiological adaptability in Brugiera sexangula and Kandel ia candel of Rhizophoraceae has been summarized as follow:1. Effect of AlCl₃ treatment on protection enzyme system and proline of Brugiera sexangula seedlingsIn order to discuss the effect of AlCl₃ to Brugiera sexangula, based on 10⁵0mmol/L AlCl₃ treatment, the activity of POD,CAT,SOD,APX and the content of soluble protein,MDA and proline in leaves and roots were studied . The results showed that the Brugiera sexangula seedlings could tolerate 50mmol/L AlCl₃ stress, but the content of MDA increased, which showed that the membrane system and active oxygen metabolism were damaged due to peroxidation. In the protection enzyme system, the activity of APX and POD increased markedly in leaves, and CAT decreased, SOD activity decreased; in roots, AlCl₃ treatment increased the activity of POD and SOD, but decreased CAT activity. Under 25⁵0mmol/L AlCl₃ treatment, the content of proline decreased evidently both in leaves and roots; the content of proline increased in leaves and roots .2. Impact of AlCl₃ on accumulation of several metal elements in Brugiera sexangula seedlingsUnder increasing of AlCl₃ concentration, the accumulation of Al was increased in leaves,stems and roots, that in roots were obvious. The absorption of Na was increased in roots, but with indistinctively changing in leaves and stems; 10mmol/L Al facilitate the absorption of K. Al restrained the accumulation of Mn,Fe. The Cu,Zn accumulation changed indistinctively. The accumulation of Ca in roots was obviously increased under 25mmol/L and 50mmol/ L AlCl₃ stress, which may mitigate the contaminate of Al.3.Effect of AlCl₃ treatment on Kadelia candel seedlings1mmol/ AlCl₃ were put on to mature hypocotyl as soon as they were planted, after three- month natural growth, the height and fresh weight of Kadelia candel seedlings changed indistinctively, but the elongation of roots were restrained.After one-month natural growth, heavy AlCl₃ treatment to Kadelia candel seedlings, after seven and fifteen days, the growth of seedlings under 50mmol/L and 25mmol/L AlCl₃ treatment stopped , which were hurt and finally dead; those under 10mmol/L AlCl₃ treatment could grow in the course of nature.In one week of 25mmol/L and 100mmol/L AlCl₃ treatment to Kadelia candel seedlings, MDA increased in leaves, activity of SOD and POD increased in certain time range, CAT activity decreased. 100mmol/L AlCl₃ made oxygenation damage heavier and reduced the photosynthesis efficiency.In roots, POD activity increased under 25mmol/L and 100mmol/L AlCl₃ treatment , activity of SOD and CAT changed indistinctively. The content of proline increased evidently both in leaves and roots.