Analysis of phosphorus nutrition efficiency of soybean genotypes with different phosphorus efficiency at blooming stage under low phosphorus stress | 低磷胁迫下不同磷效率大豆花期磷营养效率分析

Chinese. [目的]研究低磷胁迫下不同磷效率基因型大豆花期的磷营养效率。[方法]选用4个“磷低效”大豆基因型（D03、D05、D17和D18）和4个“磷高效”大豆基因型（D31、D34、D37和D38）为试验材料，采用土培试验，设高磷（+P）和低磷（-P）2个处理，分析不同磷效率大豆基因型的含磷量、吸磷量和磷的利用效率与磷效率的关系。[结果]低磷处理下，4个磷高效基因型大豆苗期植株吸磷量的优势均较明显，D34表现出较强的磷吸收能力，但其磷利用效率的适应性并未表现出优势，只有D37表现出较强的磷利用能力和吸磷能力。相关与通径分析表明，在大豆花期（-P）和（+P）处理下，大豆磷效率的高低主要是由吸磷能力的强弱来决定的，（-P）处理明显大于（+P）处理。（-P）和（+P）处理的吸磷量和磷的利用效率对磷效率直接影响均较大，而吸磷量贡献更大；间接影响均较小。低磷胁迫下，在大豆的营养生长阶段花期，磷高效基因型适应低磷的机理是不同的，磷吸收效率即吸磷量是不同基因型大豆花期磷效率的主要变异来源。[结论]该研究明确了不同磷效率基因型大豆的磷吸收效率和磷利用效率对磷效率的贡献。

English. [Objective] This study aimed to investigate the phosphorus nutrition efficiency of different soybean genotypes at blooming stage under low phosphorus stress. [Method] By using four "low phosphorus efficiency" soybean genotypes (D03, D05, D17 and D18) and four "high phosphorus efficiency" soybean genotypes (D31, D34, D37 and D38) as experimental materials, soil culture experiment was conducted with two treatments of high phosphorus (+P) and low phosphorus (-P), to analyze the relationship between phosphorus content, phosphorus uptake, phosphorus use efficiency and phosphorus efficiency of soybean genotypes with different phosphorus efficiency. [Result] Under low phosphorus conditions, four soybean genotypes with high phosphorus efficiency showed significant advantage in phosphorus uptake at seedling stage, to be specific, D34 showed relatively high phosphorus absorption capacity but no advantage in adaptability of phosphorus use efficiency, while only D37 showed relatively high phosphorus absorption capacity and phosphorus use capacity. Correlation analysis and path analysis showed that the level of phosphorus efficiency of soybean at blooming stage under (-P) and (+P) treatments was mainly determined by phosphorus absorption capacity, and that under (-P) treatment was significantly greater than (+P) treatment. Phosphorus uptake and phosphorus use efficiency under (-P) and (+P) treatments both showed great direct effects on phosphorus efficiency, and phosphorus uptake made greater contribution; however, the indirect effects were relatively low. Under low phosphorus stress, the mechanisms for various soybean genotypes with high phosphorus efficiency to adapt to low phosphorus stress were different, and phosphorus absorption efficiency (phosphorus uptake) was the main variation source of the phosphorus efficiency of various soybean genotypes at blooming stage. [Conclusion] This study revealed the contribution made by phosphorus absorption efficiency and phosphorus use efficiency to phosphorus efficiency of soybean.