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Indoor conditions set 0,5,10,15,20,25,30,35,40,45, 10 salinity gradient selection intact, compared with the same size aragon wood [Laguncularia racemosa (L.) Gaertn.F.] germination experiments seeds were placed in different salinity seawater, select the germination rate, germination potential, germination index, vigor index, mean germination germination indicators. Under outdoor conditions, through the automatic control simulation of tidal potted device test, were studied the water-soaked and salted stress on growth and physiological characteristics of aragon wood. Set 6,12,18,24 h, the four water stains gradient, salinity unified set to 25, the experimental cycle 180d, measuring plant height, number of leaves, leaf area, fresh weight of each part were measured leaf photosynthetic interaction parameters, and determination of the leaves and roots of SOD, POD, MDA, proline, soluble protein, soluble sugar and root activity, explore the impact of different of water stains time of aragon wood growth and physiological indicators. Salinity experiments 0, 10, 20, 30, 40, five salinity gradient, experimental cycle 300d studied salinity of aragon wood stem height, number of leaves, leaf area, water content and biomass allocation, photosynthetic characteristics, the activities of SOD, POD, MDA, proline, soluble protein, soluble sugar and other physiological parameters of salted response. Finally, we discuss the different Salinity, Na, K, Ca, Mg, Cl, N, P, C, etc. The content of the element, distribution and relations. The results show that: salinity less than 25 aragon wood germination rate changes little, and are close to 100% germination rate began to decline when the salinity, in salinity 45 processing, seed the germination rate of only 4%. Seed germination potential at a salinity of 10 reached the maximum, as the salinity is increased gradually reduced germination potential, germination potential drop to zero when the salinity of more than 30. Aragon wood optimum germination salinity range of 5 to 25, although when the salinity is more than 30, the germination of seeds by the inhibition of germination index, vigor index, the average germination times and other indicators show that, but there is still higher germination rate (73 ± 9%). When brine salinity of 45 seeds were placed, the germination rate is close to zero, 15d will be placed in the sea water of low salinity (<25) and can germinate, high salinity water is not interested aragon wood seeds produce toxic effects. Under different water-soaked time the aragon wooden seedling height with increasing water-soaked time increased, the number of leaves in all treatments not significant (p> 0.05), the increase of the leaf area with water stains time increases, this may be a seedling increase the effective photosynthetic area, increase the rate of carbon assimilation in order to adapt to the Root long-term water stains. Aragon wood seedlings under different water-soaked time processing, roots, stems, leaves, and plant biomass is first increased and then decreased, reaches a maximum, and then declining trend in 12h processing. More complex root to shoot ratio trend, was the \The rise may be due to long water stains, resulting aragon wood to grow a large number of breathing roots, increasing the proportion of the roots. . Of aragon wooden leaf net photosynthesis rate 12h maximum processed water stains, and 24h processing net photosynthetic rate of less than 50% of maximum, intercellular CO 2 concentration trend Similar with the net rate of photosynthesis. Chlorophyll content increases with increasing water stains time, chlorophyll a / b ratio in 24h processing also reached the highest value, this may be to improve the efficiency of plant photosynthesis plants by increasing the content of photosynthetic pigments. 4. The water stain treatment under aragon the Mugen leaf SOD activity, POD activity, MDA, proline content overall trend is the increase as the water-soaked time increases, this reflects aragon wood membrane system there was a certain peroxide phenomenon, but the plants have enough free radical scavenging enzymes, to ensure the normal physiological activity. Soluble protein and soluble sugar content is also increased with increasing water stains time aragon wood by water stress can produce more osmotic adjustment substance of osmotic pressure to balance the body. 5. Salinity of aragon wood stem is not significant, salinity 0 handle incremental various other processing incremental salinity 0 94.6%, 88.2%, 73.1%, 35.5%. Leaf area, leaf number and increments, all reflect the low-salt promote high salt rejection mechanism, reaches a maximum in the salinity of 10 treatments, and then decreased with increasing salinity, salinity 40 aragon wood growth has been greatly suppressed. Aragon wood under high-salt treatment increased root biomass distribution, reducing the area of ??leaves to reduce water loss, increase nutrient absorption area of ??the root. The water content of the root, stem, leaf water content in salinity 40 treatment reaches the maximum, which aragon wood to resist excessive physiological drought store more water to dilute ion concentration to ensure normal osmotic pressure, balance the absorption of nutrients. Aragon wood chlorophyll content as the salinity increases first and then decreased, the salinity 30 processing chlorophyll and carotenoids dropped to the lowest, salinity 40 treatment increased significantly, leaf net photosynthesis rate in the salinity of 10 processing, and then gradually decreased. Water use efficiency of leaves reflects aragon wood to be able to adjust its physiological metabolism, increase water use efficiency to adapt to high salinity (30), but the salinity is too high (40) and curbed its water use efficiency. 7. Blades POD activity in salinity reached 40 when declining salinity 20:00 leaf SOD activity reached a maximum of 1200 U · g -1 FW salinity ≤ 30 POD activity in leaves and SOD activity can be maintained at a relatively high level, strong stress resistance in the salinity aragon wood. MDA and proline content is gradually increased, high salinity also affects the carbohydrate metabolism of soluble sugar and soluble protein when salinity is higher than 30 content decreased. 8 in different Saline processing, Na, K, Ca, Mg, Cl element content difference obvious rise of Na and Cl element content as the salinity increases, while the K, Ca, Mg element content as the salinity of the decreases, show that of Na and K , the of Ca 2 , exists between Mg 2 obvious antagonism. The paper concludes that salinity aragon wood C, N, P element content did not significantly influence, but the C: N ratio affects a very significant salinity 0:00 C: N to 73.04 salinity 20:00 a ratio of 86.84, salinity 40 C: N dropped to 61.71.
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