Effect Of Soil Texture And Phosphate Fertilizer Rate On Phosphorus Availability In Xinjiang Cotton Field

In order to discuss the utilization efficiency of soil phosphorus on cotton field soil, reduce the usage of phosphate fertilize, provide a theories basis for cotton field in Xinjiang by apply phosphorus fertilizer with reason, choice three different soil texture in northern Xinjing, through pot experiment study the effect on soil phosphorus with different phosphate fertilizer rate,and the changes of soil phosphorus content without phosphorus fertilizer apply; on the salinization cotton field in southern Xinjing, study the effect on soil phosphorus on cotton field with different phosphate fertilizer rate, and disscuss the pertinence of phosphorus and salt preliminary. The main results are as follows:1.The effect of different phosphate fertilizer rate under different soil texutre on soil phosphorous validity on pot experimentThe test result of experimental crop by cotton 3 years continuously show that, with the increase of phosphate fertilizer rate, the available phosphorus content show the increase trend, different texture show clay>loam>sandy, and the correlation of available phosphorus and phosphate fertilizer apply rate is observably. The ability of sandy, loam and clay's soil phosphorus supply decreased as time goes on, and the availability nutrient content by plant decreased. Compared with 2007 and 2009, on flowering stage, the low phosphorus (75 kg·hm-2, 150 kg·hm-2)treat's available phosphorus of sandy, loam and clay average reduced 11.61%, 4.44% and 27.01%, respectively; high phosphorus(225 kg·hm-2, 600 kg·hm-2)treat average reduced 37.25%, 49.22% and 56.76%;On boll stage, the low phosphorus treat average reduced 23.56%, 17.12% and 24.43%,respectively; high phosphorus treat average reduced 21.97%, 13.22% and 29.45%. But the available phosphorus content of loam and clay is more than sandy, it is show that the soil phosphorus's buffer capacity of loam and clay are high, and the buffer energy are greater, the phosphorus can applied lots by one time, one or two years later can don't apply phosphorus or apply little, but the sandy should pay attention to apply frequently and less,prevent doff fertilizer on later stage.2.The effect of different phosphate fertilizer rate on cotton field soil phosphorous validity on field experimentPhosphate fertilizer application can increase the available phosphorus content, total phosphorus content and phosphorus activation coefficient(PAC). Compared with CK the available phosphorus content of low phosphorus treat increased 35.31%, high phosphorus treat increased 76.05%; Total phosphorus content of low phosphorus treat increased 12.44%, high phosphorus treat increased 33.64%; PAC of low phosphorus treat increased 20.67%, high phosphorus treat increased 35.48%. The change range of 0～20 cm is more than 0～20 cm. On flowering stage, low phosphorus treat of accumulate of dry matter and the accumulate of phosphorous is inhanced 31.44% and 44.69%, high phosphorus treat increased 20.93% and 20.16%; On opening stage, low phosphorus treat of accumulate of dry matter, yield and the accumulate of phosphorous is inhanced 15.72%, 29.88% and 46.56%, high phosphorus treat increased 17.14%, 16.34% and 7.51%. When apply phosphate fertilize 75 kg·hm-2～150 kg·hm-2, there is a bigger contribute for the accumulate of dry matter, the yield of seed cotton, and the accumulate of phosphorous,and it can be a reasonable phosphate fertilize application rate.3.The effect of phosphate fertilizer rate on cotton field soil salinityOn different procreate stage and soil layer, the pertinence of phosphate fertilizer application rate, total phosphorus and available phosphorus with the total salt and each ion of salinity are different, the tatal salt of 0～20 cm is assemble; but with the ion is not obviously. The pH on low phosphate treat is more than high phosphate treat. The pertinence of phosphate fertilize apply rate, total phosphorus and available phosphorus with pH show that the correlation is minus on 0～20 cm and 20～40 cm soil on seedling stage, and on flower and boll stage,opening stage is plus.