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Casuarina China's southeast coastal shelterbelt planting trees, hard to replace a huge role to play in the sand-fixing, improve the ecological environment and timber. The Southern Coastal Sandy universal phosphorus and soil phosphorus has been healthy growth of the important factors affect the coastal Casuarina shelterbelts. Plus Casuarina shelterbelt create the majority has entered into over-ripe stage, in the coastal shelterbelt practice found even planted Casuarina forest soil phosphorus content decreased, one of the reasons for the coastal shelterbelt difficult. Therefore, to carry out the of Casuarina different varieties of phosphorus stress physiological response and the adaptive mechanisms, screened out of tolerance to low phosphorus Casuarina fine lines, of coastal shelterbelt renovation, the woodland soil management and sustainable management are very important practical significance. In this study, the real problem in the coastal protection forest management, in order to filter the Casuarina tolerance to low phosphorus and phosphorus efficient varieties for the purpose of Different Phosphorus simulated in the laboratory environment, the introduction of Australia's Casuarina source, 8 Casuarina the clonal test object, Determination of total moisture content, plant C / N, the plants total phosphorus content, the rhizosphere soil available phosphorus, total phosphorus, pH value and other indicators of the Casuarina organizations under different phosphorus stress, to carry out the provenance of Casuarina clones to Low Phosphorus Stress seedling stage adaptation mechanisms. Select Casuarina source 18153,18154,18157,18296,18298,18312 is, Dongshan County, Fujian provenance as the control environment of controlled low phosphorus (P0) and phosphorus (P1), the stress after 6 months, Determination of Different Provenances seed germination rate, the physiological indicators rhizosphere soil nutrients and moisture content, the test results show that: the provenance 18298 grain weight, germination rate is the highest; followed Dongshan germination rate of the seed source; provenance germination rate and seeding experiment emergence basically the same; Dongshan provenance in height growth and diameter growth are the largest in the P1 conditions, but significant difference in growth between P0 and P1 conditions; phosphorus stress on provenance 18157 18298,18312 height growth impact is not significant; Dongshan provenance has a significant advantage in the biomass accumulation of phosphorus stress on the provenance 18153,18154,18157,18296,18298,18312 of biomass accumulation did not significantly affect; phosphorus stress, Dongshan provenance, provenance: 18153,18154,18157,18296,18298,18312 sprig of chlorophyll a and chlorophyll b content between the block was a significant difference. Phosphorus stress on Dongshan provenance, 18157,18298 sprig chlorophyll content has a significant influence; phosphorus stress on Dongshan provenance and 18153 plants moisture content greater impact; phosphorus stress on Casuarina sprig total phosphorus ; Under Low Phosphorus Stress on Different Provenances rhizosphere soil pH lower than normal for phosphorus conditions; the phosphorus stress can significantly increase the the Different Provenances rhizosphere soil available P; applied phosphate fertilizer in the short term increase soil total phosphorus content had no significant effect. In Casuarina clones phosphorus stress test the Casuarina level 2, Long, Cham 1, A13, 501,701, Nanshan, Pu 20 clones, in a controlled low phosphorus (P0) and high phosphorus environment (P1), after the stress of one year, the clones height growth, biomass, physiological indicators, and rhizosphere soil nutrient status indicators were measured and found: phosphorus stress on the growth of Pu 20 height significant impact, while the other seven clones height impact is not obvious; low phosphorus stress significantly affect the clones 701 and Nanshan 7 to diameter growth, but the the clonal level 2, Long, Cham, A13, 501, Pu 20, diameter growth is not sensitive to Low Phosphorus Stress; phosphorus stress on different clones of Casuarina aboveground biomass accumulation did not significantly affect; Under Phosphorus Deficiency, level 2, Yakuza 4, Cham 1, A13 SOD activity showed rapid decrease with temperature decrease, and then a slow recovery; the clones 501 of SOD activity began to show the most rapid increase has slowed in November, SOD activity increased; 701, Nanshan 7 Pu 20 SOD activity showed a slow rise and fall; under low phosphorus stress, Casuarina different clones A13 and the Nanshan 7 sprig content of malondialdehyde; under low phosphorus stress Casuarina different clones rhizosphere soil pH value than normal for phosphorus conditions: clone Long 4, A13, the Po 20 sprig phosphorus accumulation of phosphorus stress sensitive; phosphorus stress can significantly increase the Different Provenances rhizosphere soil available P; applied phosphate fertilizer in the short term effect of increased soil total phosphorus content was not significant. Under Phosphorus Deficiency the Casuarina different varieties to Low Phosphorus Stress stress, physiological and morphological indicators of different Casuarina provenances and clones change through the seedling stage test, which shows the low phosphorus stress adaptability, adaptation mechanisms. Casuarina different provenances and clones of each plant physiological and biochemical indexes and rhizosphere soil physical and chemical properties of index changes in the conditions of P0 and P1, and the Casuarina to Low Phosphorus Stress adaptation mechanism, under low phosphorus stress, soil low phosphorus content available for absorption and utilization of Casuarina Casuarina change their physiological and morphological indicators, such as increasing below-ground biomass accumulation, and enhance the in vivo protective activity of the enzyme secreted more acidic substances to activate fixed to increase their absorption and utilization of phosphorus in the soil P. Comprehensive Casuarina different provenances and clones in P0 and P1 conditions seedling stage high growth, physiology, root rhizosphere soil nutrient indicators of change, primaries provenances 18312 and clones A13, Long, the Cham 1,501 as coastal shelterbelts second generation reforestation species.
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