【摘要】 目的：探究黄连根系响应低磷胁迫的策略，为理解栽培黄连连作障碍机制奠定基础。方法：以月为单位连续采集一周年2年生黄连样本，测定其根茎生物碱和氮(N)、磷(P)和钾(K)三种元素含量；测定水培试验黄连的生物量、根系形态、根系有机酸分泌量、营养元素含量等。结果：黄连根茎生物碱含量与磷含量成线性正相关，而与氮和钾含量无相关性。水培实验中，黄连地下部生物量在低磷和正常磷水平下无显著差异。总根长、根表面积、根体积、平均直径在两个磷浓度处理下均无差异。低磷处理中根系苹果酸和草酸分泌速率显著高于正常磷处理，以苹果酸尤为突出。根系磷含量低磷处理中显著低于高磷处理，而锌含量呈相反规律。叶片中磷、钾、铁、猛、铜含量在两个磷处理中并无明显差异。结论：黄连根系主要通过生理改变响应低磷胁迫，锌可能是影响黄连根系有机酸代谢的重要元素。更多还原

【Abstract】 Objective:To explore the Huanglian root system response strategy to low phosphorus (P) stress,and provide a basis for understanding the mechanism of successive cropping obstacle.Method:Rhizome alkaloid and nitrogen (N),P and potassium (K) contents of biennial Huanglian collected monthly for one year were detected.Biomass,root morphology,organic acid secretion and nutrient element content of Huanglian in hydroponics were determined.Result:The alkaloid content of Huanglian rhizome was linearly positively correlated with P content,but not with N and K content.In the hydroponic experiments,there was no significant difference between the biomass of Huanglian underground at low and normal P levels.The total root length,root surface area,root volume and mean diameter had no difference under two P concentration treatments.The rate of root malic acid and oxalic acid secretion in the low phosphorus treatment was significantly higher than in the normal P treatment,especially malic acid.Root P content in the low P treatment was significantly lower than in the high P treatment,while root zinc content showed the opposite pattern.There was no significant difference in leaf P,K,Fe,Mg and Cu contents between the two P treatments.Conclusion:The roots of Huanglian mainly respond to low P stress through physiological changes.Zn may be an important element affecting the organic acid metabolism of Huanglian roots.更多还原