不同供磷水平对辣椒根系形态和根际特征的影响

以辣椒品种线椒王为试验材料，采用盆栽方式，通过分析不同施磷水平下辣椒根系形态和根系生理的变化，探究辣 椒磷高效利用的主要根系及根际过程。结果表明，辣椒地上部和根系生物量随供磷水平的增加呈现先增加后下降的趋势，整 株磷浓度以及整株磷累积量呈增加趋势。随供磷水平增加，根系总根长呈先增加后下降趋势，根系平均直径、根冠比呈逐渐 降低趋势；辣椒根系菌根侵染率和土壤酸性磷酸酶活性呈现先增加后下降的趋势。相关分析结果表明，土壤有效磷浓度和整 株磷浓度与根系平均直径、菌根侵染率呈极显著负相关，与总根长可用一元二次方程拟合，表明辣椒根系适应低磷的根际特 征可能是通过增加根系生物量及总根长，同时降低根系平均直径来实现的。

Effect of Phosphorus Supply on Root Morphology and Rhizosphere Traits in Pepper

Taking ‘Xianjiaowang’ pepper as test material and by potted culture method，this paper explored the main root system in phosphorus（P）high efficient utilization and rhizosphere process through analyzing the changes in mophology and physiology of pepper root system under different phosphorus application levels．The results showed that the biomass of pepper overground part and root system increased firstly then decreased with the increase of P application．Along with the increase of P supply，the total root length showed a tendency of first increase then decrease，and the average root diameter and ratio of root to shoot decreased gradually．The rate of arbuscular mycorrhizal colonization and activity of soil acid phosphatase in pepper root system increased firstly then decreased．The correlation analysis showed that soil Olsen-P concentration and whole plant P concentration were extreme significant negatively correlated with average root system diameter，and root arbuscular mycorrhizal colonization；and could be fitting with the total root length by quadratic equation with one unknown，indicating that the rhizosphere trait of pepper root system adapted to low P might be achieved by increasing root biomass and total root length，while reducing the average diameter of root system．