低磷胁迫对大豆根系生长特性及分泌 H+和有机酸的影响

以不同基因型大豆nf37和冀黄13为材料，水培法研究大豆根系周围的酸化现象，并通过对大豆根干重、根冠比以及植株中磷含量的测定来探讨不同基因型大豆对枸溶性磷肥的利用效率。结果表明，低磷胁迫下，不同基因型大豆的根系均能主动向外界环境分泌H+；经HPLC分析得出，柠檬酸、草酸、酒石酸和苹果酸是主要分泌的有机酸；当向培养介质中添加枸溶性磷肥后，不同基因型大豆均可有效利用这一难溶性磷肥。无论是H+分泌量、有机酸分泌量还是对枸溶性磷肥的利用效率，耐低磷基因型大豆（nf37）都显著高于磷敏感基因型大豆（冀黄13）。表明，低磷胁迫均导致不同基因型大豆根系向介质中分泌H+和有机酸，同时还诱导大豆根系的加速生长，各项指标在耐低磷和磷敏感大豆基因型之间表现出显著差异，这可能是不同基因型大豆对枸溶性磷肥吸收、利用效率不同的原因。

Effect of P deficiency stress on soybean root system and its secretion of H + and organic acid

Different genotypes of soybean nf37 and Jihuang 13 were selected as materials,their acidification around the root system(the content of H+ and secretion of organic acids in soybean nutrient solution),the root dry weight,root to shoot ratio and phosphorus content of plants were studied by solution culture to explore the efficiency of insoluble phosphate fertilizer in different soybean genotypes.The results showed that both of the soybean genotypes could secrete H+ and organic acids to external environment un...