大豆种质耐低磷与耐铝毒部分指标及其相互关系的研究

通过溶液培养试验 ,对来源于华南酸性土壤的 5个大豆品种的地上部及根部耐低磷及耐酸铝部分指标进行了系统的研究。研究结果表明 ,大豆在磷效率和耐铝毒特性方面存在着一定的差异 ,大豆品种 6 2号、乐昌及广州大粒具有较高的磷效率和耐铝毒特性。在低磷及铝毒胁迫下它们具有较高的生物量、磷含量、叶面积、叶绿素含量、总酸分泌量以及主根长。低磷和铝毒胁迫严重影响地上部磷的吸收 ,高磷能缓解铝毒。铝浓度不同处理大豆的地上部无显著差异 ;但在铝毒胁迫下 ,根部的铝浓度比地上部高 5～ 6倍 ,且品种间存在显著差异。本研究初步确定了大豆耐低磷与耐铝毒的相关关系

Tolerance indices for Pdeficiency and Al toxicity and their interactions in soybean

Some tolerance indices for P deficiency and Al toxicity in fi vesoybean genotypes collected from South China were studied in nutrient solutio n culture. The results indicated that genetic variation existed within the test e d soybeans in P efficiency and Al tolerance. Soybean varieties No.62, Le Chang a nd Guangzhou had relatively high P efficiency and Al tolerance. Under low P and Al toxicity conditions, they were relatively higher in biomass, P content, leaf area, chlorophyll content, total acid exudation and tap root length. Low P and A l toxicity affected shoot P uptake, and increased concentration P in nutrient so lution could significantly ameliorate Al toxicity in soybean. There was no sign i ficant variation in Al concentration in the shoot, but under Al toxicity stress, the Al concentration in the root was five or six times as that in the shoot, wi th significant differences among genotypes. Our results indicate a possible rel a tionship between P efficiency and Al tolerance in soybean, but this relationship should be further verified by linkage analysis with the molecular marker technique.