主成分分析磷、砷交互作用对水稻生长的影响

Application of Principal Component Analysis to Studying the Effects of Phosphorus and Asenic Interaction on the Growth of Rice

为探究不同磷效率水稻品种对磷、砷交互作用的耐受性及响应机制。试验采用一个耐低磷和一个低磷敏感水稻品种,设置3个磷水平,4个砷水平,用盆栽土培方法培养水稻幼苗,处理35 d后测定水稻的株高、叶宽、叶色、干重、磷含量、磷累积量、砷含量和累积量等指标,并进行主成分分析。结果表明,磷、砷处理对水稻株高等各指标影响较大。同一浓度砷处理时,提高磷处理浓度对砷毒害有一定的缓解作用,耐低磷水稻品种较磷敏感水稻品种表现出更好的缓解效果。同一磷水平,砷在较低浓度时对水稻生长具有刺激作用,水稻叶色、磷含量和磷累积量随砷浓度的增加呈先上升后下降的趋势。磷、砷浓度增加均能促进水稻对磷、砷的吸收及其在地上部的累积。主成分分析表明,磷_(150)砷_(25)处理下不同磷效率水稻各项生理指标最理想,高浓度磷处理水稻各项指标比较好,随着磷处理浓度的下降,各项指标逐渐变差。高浓度磷、砷处理,耐低磷水稻虽然吸收和累积相对较多的砷,但植株仍能保持较强的磷吸收和累积能力,耐受砷毒害,使植株株高、叶宽、叶色等生长指标受抑较小;磷敏感水稻株高、叶色和干重受影响最大,受害严重。

The objective of this study was to explore the tolerance and response mechanism of rice varieties with different phosphorus efficiency on the phosphorus （P）-arsenic （As） interaction. One low-P tolerant and one low-P sensitive rice varieties were used to get rice seedlings by soil pot-cultivation. Three phosphorus levels and four arsenic levels were set up to test rice plant height, leaf width, leaf color, dry weight, content of phosphorus, phosphorus accumulation after 35 days＇ processing. Principal component analysis was carded on and the results showed that P and As treatment had great influence on rice index such as rice height.At the same As level,the higher concentration of P had a certain role in the mitigation of As toxicity and low-P tolerant rice cultivars showed better relief effects than low-P sensitive ones. At the same P level, the SPAD value, content of phosphorus and total P of the rice varieties changed with a similar trend of descending after ascending. The increasing of P and As concentration both could promote rice seedlings absorption and accumulation of P and As. Principal component analysis showed that each of physiological index of the two rice varieties was desirable under the treatment of P 150 mg/kg and As 25 mg/kg. Each index of rice under high level of phosphorus was relatively good and would turn bad gradually by the declining of the P concentration. At the high level of P and As, two rice varieties absorb more P and As, the plant height, leaf weight and SPAD value of low-P tolerant rice variety were larger than those of low-P sensitive rice variety, indicating that the uptake capability of rice to As might be related to its P nutrient character and its competitive absorption between P and As.