The Relationship Between The Characters Of Different Maize Varieties And The Inorganic Phosphorus In Soil Under Salt Stress

Maize is China’s third largest food crops,its resistance to salt is poor,salt stress inhibits plant growth and reduce production. The area of the Saline soil in our country is very large and widely distribute,affect the crop yield, for utilize the saline soil reasonably improve the yield and quality of maize, our research through the pot experiment in laboratory,studied the relationship between the seedling traits and the inorganic phosphorus in soil of different maize varieties under salt stress、through the field experiment of salt pond,studied the changes of rhizosphere soil inorganic phosphorus etc in the whole stages of different maize varieties under salt stress, in order to provide theoretical support to select the suitable maize varieties in saline soil area.The pot experiment results show that:1、With the concentration of salt stress increase,the plant fresh weight, plant height and phosphorus uptake of the test maize were significantly decreased, root-shoot ratio increased significantly. The significant difference was observed in plant fresh weight, plant height, root-shoot ratio, phosphorus uptake between the different maize varieties.2、The order of the inorganic phosphorus content in test soil is Ca10-P>Ca8-P>Fe-P>Al-P>Ca2-P>O-P; with the concentration of salt stress increase, available phosphorus in Zhengdan 958 and Danyu 92 soil decreased;in Zhengdan 958 soil the Ca2-P content increased under low salt level,decrease under high salt level,in Danyu 92 soil the Ca2-P content increased only no salt,the are decrease,Danyu 92’s descent extent is larger than Zhengdan 958; the Ca8-P content decreased in Zhengdan 958 and Danyu 92 soil, Danyu 92’s descent extent is larger than Zhengdan 958; the Al-P content decreased, the Fe-P content increased, the O-P content has little change after planting two varieties of maize,the changes of Ca10-P content is in contrast to the Ca2-P.3、There have the significant direct correlation between the maize plant fresh weight、plant height 、 available phosphorus in soil 、 Ca2-P 、 Ca8-P content and the amount of phosphorus,there have no significant correlation between the total phosphorus in soil and the inorganic phosphorus content、the amount of phosphorus. There have the significant direct correlation between the Ca2-P、Ca8-P content and available phosphorus in soil,the order of the inorganic phosphorus to available phosphorus’ s direct path coefficient Ca2-P(0.583)>Ca8-P(0.523)>Al-P(0.124)>Ca10-P(0.06)>Fe-P(-0.196)>O-P(-0.293).4、With the concentration of salt stress increase, the acid and alkaline phosphatase activity gradually decline, Danyu 92’s descent extent is larger than Zhengdan 958. There have the significant correlation between the amount of phosphorus、available phosphorus、Ca2-P、Ca8-P content and the phosphatase activity.The field experiment results show that:1、Ca2-P、Ca8-P、Al-P、Fe-P、O-P content in soil under salt stress is apparently lower than CK. With the maize growth,Ca2-P content decline, Ca8-P content is decline and increase followed,which is least on July 31.In Zhengdan 958 soil Ca2-P、Ca8-P、Al-P、Fe-P content is higher than Danyu 92. Two varieties Ca2-P content in rhizosphere soil were significantly higher than that in non rhizosphere without salt stress,while which is lower than that under salt stress; Ca8-P、Al-P、Fe-P content in rhizosphere soil is higher than that in non rhizosphere,while O-P isopposite; Ca10-P content have differences between the different varieties, in Zhengdan 958 soil Ca10-P content in rhizosphere soil is lower than that in non rhizosphere,while Danyu 92 is opposite.2、With the concentration of salt stress increase, Na+、Cl- content、EC、p H value in soil solution were significantly increased. Na+ content in soil is the highest on July 31 and August 21, Cl- content is higher than before after July 31. p H value in Zhengdan 958 soil is lower than Danyu 92 each time. Na+ content in rhizosphere soil were significantly lower than that in non rhizosphere,while Cl- is opposite. p H value in rhizosphere soil solution is lower than non rhizosphere.3、With the concentration of salt stress increase, two maize varieties phosphatase activity gradually decline,with the plant growth,the phosphatase activity increased in the first four period, the phosphatase activity in rhizosphere soil were significantly higher than that in non rhizosphere.4、With the concentration of salt stress increase,maize production、available phosphorus in soil is significantly descent.Zhengdan 958’s production、available phosphorus in soil is higher than Danyu 92.5、The phosphorus forms absorbed and utilized by plants is different in different growth periods. Throughout the whole growth stage,the absorption and utilization to Ca2-P、Ca8-P is enhanced gradually with the plant growth. The correlation analysis between the amount of phosphorus and the phosphorus in soil at maturing stage showed that in the inorganic phosphorus forms which can be absorbed and utilized by the plant is Ca2-P、Ca8-P、Al-P and Fe-P, there have the significant direct correlation between the available phosphorus、total phosphorus and them.6、There have the significant correlation between the available phosphorus、Ca2-P、Ca8-P、Al-P、Fe-P and maize production under salt stress, Ca2-P、Ca8-P is the effective phosphorus source to be absorbed and utilized by plants; there have the significant correlation between the amount of phosphorus and maize production; the significant inverse correlation between production and Na+、Cl- concentration、EC value, the significant direct correlation between production and the phosphatase activity.