【摘要】 通过营养液栽培试验研究大豆适应低磷胁迫的机理 ,试图找出供试大豆在水培条件下对低磷胁迫下的适应性与田间表现的关系 ,为快速选育磷高效品种提供具有参考价值的实验数据。结果表明 :在水培条件下 ,大豆在磷效率方面存在着显著的基因型差异。在总体磷效率 (以生物量为标准 )方面和磷吸收效率 (整株含磷量 )方面 ,结果与田间试验表现基本一致。BX10和GD1属于磷高效对磷不敏感基因型 ,BD2属于磷低效对磷不敏感基因型 ,BX11和GD2属于磷低效对磷敏感基因型 ,BD1属于磷高效对磷敏感基因型 ,GD3和GD4表现不稳定。从磷的利用效率 (单位磷所产生的生物量 )来看 ,基因型间没有显著差异。说明即使在水培条件下 ,磷利用效率对大豆总体磷效率贡献也不大 ,大豆总体磷效率主要是由吸收效率决定的。与田间反应不同的是 ,水培条件下磷吸收效率高的基因型 ,具有较长的根长与较大的根表面积。说明在介质有效磷分布均匀的条件下 ,根形态性状对磷吸收效率起一定的作用。更多还原

【Abstract】 A nutrient solution experiment with eight soybean genotypes was carried out to study the mechanisms of soybean further in adaptation to low P stress and to elucidate the relationship between these adaptive responses in the field and in nutrient solution culture so as to provide valuable experimental data for rapid genetic improvement of P efficiency in soybean. The results indicated that there was significant genotypic variation in P efficiency among the eight soybean genotypes tested. Based on the overall P efficiency (defined as biomass) and P acquisition efficiency (defined as P content), the results generally resemble those in the field experiment. Genotype BX10 and GD1 were P efficient but non-responsive; genotype BD2 was P inefficient and non-responsive; genotype BX11 and GD2 were P inefficient but responsive; genotype BD1 was P efficient and responsive; the other genotypes, GD3 and GD4 were unstable in the performance. Moreover, there was no significant genotypic variation in P utilization efficiency (defined as biomass produced per unit P content) among the eight soybean genotypes, indicating that P utilization efficiency contributes less than P uptake efficiency to overall P efficiency of soybean even under hydroponic conditions. Therefore, the overall P efficiency of soybean was mostly determined by P acquisition efficiency even in nutrient solution culture. Differing from that in the field experiment, the P-efficient genotypes had relatively longer root length and larger root surface area in nutrient solution culture. This indicates that root morphological traits mainly affect P acquisition efficiency under conditions with uniform distribution of available P in the growth medium.更多还原