盐胁迫玉米土壤中无机磷组分变化规律的研究

Studies on Variation of Inorganic Phosphorus Components in Maize Soil under Salt Stress

在田间盐池内设置5个盐浓度水平,种植两个玉米品种,研究了盐胁迫下玉米不同生长期土壤中无机磷组分变化规律,探讨各组分磷在玉米根际与非根际土壤中的含量差别、各组分磷的有效性及与玉米吸磷量的关系。结果表明:供试土壤无机磷各组分含量顺序是:Ca10-P>Ca8-P>Fe-P>Al-P>Ca2-P>O-P;无盐处理土壤中,Ca2-P含量在整个玉米生长期都保持很高水平,而所有盐胁迫处理土壤中,Ca2-P含量均随着玉米生长而下降,且降幅显著。在盐胁迫处理下,土壤中Ca8-P与O-P的含量在玉米生长的各个时期均显著低于非胁迫土壤,Al-P与Fe-P的含量均极显著低于非胁迫土壤;玉米根际土壤中Ca2-P、Ca8-P、Al-P、Fe-P含量高于其在非根际土壤中的含量,O-P含量低于其在非根际土壤中的含量,盐胁迫下玉米土壤中Ca10-P含量在两个玉米品种间差异较大。盐胁迫下,玉米在整个生长过程中对Ca2-P与Ca8-P的吸收利用随玉米生长阶段的推进而逐渐增强。无机磷各组分中能被植物吸收利用的主要是Ca2-P、Ca8-P、Al-P和Fe-P。

To set five salt concentration levels in salt ponds, planted two kinds of maizes in the fields, studied the change rule of soil inorganic phosphorous components in different growth stages of maize under the salt stress, discussed the content of phosphorus in maize rhizosphere and non-rhizosphere soil, the effect of inorganic phosphorus fractions and the relationship between phosphorus content and phosphorus uptake. These results indicated that the order of inorganic phosphorus components were Calo-P〉Cas-P〉Fe-P〉A1-P〉Ca2-P〉O-P, the content of Ca2-P in non-salt treatment soil was very high in the whole growth period of maize, the content of Ca2-P declined with the maize growth in all salt stress treatment, and declined significantly. The content of Cas-P, O-P in salt stress treatment was lower than non-salt stress treatment in different periods of maize, the content of Fe-P and A1-P was lower significantly than non-salt stress treatment. The content of O-P in maize rhizosphere soil was less than non-rhizosphere soil. And the content of Ca2-P, CaB-P, A1-P, Fe-P was higher than non-rhizosphere soil. Under the salt stress, the content of Calo-P in maize soil was different between the 2 varieties. Throughout the whole growth stage of maize, the absorption and utilization of Cas-P and Ca2-P were increased gradually with the plant growth under salt stress. And Ca2-P, CaB-P, AI-P and Fe-P were mainly absorbed and utilized by plants in each component of inorganic phosphorus.