缺磷胁迫下的大豆根系形态特征研究

采用砂培方法研究了缺磷胁迫对大豆根系形态特征的影响，结果表明：缺磷胁迫条件下，大豆根长、根表面积和根体积均比正常供磷条件下增加，0—1．0mm直径下的根长显著高于正常供磷条件，但根长在不同根直径下的比例并没有显著差异，缺磷胁迫和正常供磷处理下0～1．0mm的根长比例均在90．0％左右；缺磷胁迫降低了大豆的磷吸收效率，而增加了大豆的磷利用效率；大豆根长、根表面积和根体积与磷吸收效率呈显著的负相关，而与磷利用效率呈显著的正相关。因此，大豆根系形态与磷的吸收利用密切相关。图2，表4，参16。

Root Morphology of Soybean (Glycine max L.) under Phosphorus Deficiency Stress

Pot culture experiments were carried out to study the effects of phosphorus deficiency stress on root morphology of soybean （ Glycine max L. ）. The results showed that root length, root surface area and root volume all increased under P deficiency stress than that under normal P supplying condition, and the root length among 0 - 1.0 mm diameter was significantly higher than that in normal P supplying condition. However, the root length percentage among different diameters was no significant different between P0, P10 and P50 treatment, and the root length percentage at 0 - 1.0 mm diameter was about 90% whether in P deficiency stress or in normal P supplying treatment. Moreover, P deficiency stress decreased efficiency of P absorption in soybean, but the reverse was true for efficiency of P utilization. Further analysis showed that there was a significant negative correlation between root morphology （including root length, root surfacearea, root volume） and efficiency of P absorption, however, there was a significant positive correlation between root morphology and efficiency of P utilization. Thus, there was a close relationship between root morphology and P uptake, utilization in soybean.