外源硒对咸丰白术生长及其根际土壤理化性质的影响

Effects of Exogenous Selenium on the Growth and Physical and Chemical Properties of Rhizosphere Soil of Atractylodes macrocephala in Xianfeng

目的:研究外源硒对咸丰白术生长及其根际土壤性质的影响,并筛选出有利于白术生长的最佳施硒量。方法:通过大田试验,使用不同浓度(5、10、15 mg/m^(2))的亚硒酸钠水溶液对白术进行喷施,在白术的不同生长时期共计喷施3次。结果:相比于对照处理(清水),低浓度的硒处理(5 mg/m^(2))可以增加白术的叶面积、比叶面积和产量,增幅分别为6.7%、8.8%和23.2%,同时显著提升白术根际土壤的碱解氮、速效磷和速效钾含量,增幅分别为14.6%、18.6%和12.8%。高浓度的硒处理(15 mg/m^(2))可显著提高白术根际土壤的速效磷和速效钾含量,增幅分别为10.7%和5.3%,但对白术的生长表现为综合抑制作用。综合效应分析表明,外源硒对白术的生长呈现低浓度促进,高浓度抑制的作用。结论:咸丰白术的适宜施硒量为5 mg/m^(2)的亚硒酸钠水溶液,通过改变根际土壤养分含量可能是外源硒影响咸丰白术生长的重要原因。

Objective:To study the effects of exogenous selenium on the growth and rhizosphere soil properties of Atractylodes macrocephala in Xianfeng,and to screen out the optimal selenium application amount for the growth of Atractylodes macrocephala.Methods:Through field experiments,sodium selenite aqueous solutions with different concentrations(5,10,15 mg/m^(2))were used to spray Atractylodes macrocephala for 3 times in total at different growth stages.Results:Compared with the control treatment(water),low concentration selenium treatment(5 mg/m^(2))could increase the leaf area,specific leaf area and yield of Atractylodes macrocephala by 6.7%,8.8%and 23.2%,respectively.Meanwhile,the content of alkali-hydrolyzed nitrogen,available phosphorus and available potassium in Atractylodes macrocephala rhizosphere soil significantly increased by 14.6%,18.6%and 12.8%,respectively.High concentration of selenium(15 mg/m^(2))could significantly increase the contents of available phosphorus and available potassium in Atractylodes macrocephala rhizosphere soil by 10.7%and 5.3%,respectively,but showed a comprehensive inhibitory effect on the growth of Atractylodes macrocephala.The comprehensive effect analysis showed that exogenous selenium promoted the growth of Atractylodes macrocephala at low concentration and inhibited the growth of Atractylodes macrocephala at high concentration.Conclusion:The suitable selenium content of Atractylodes macrocephala in Xianfeng is 5 mg/m^(2) of sodium selenite aqueous solution,and changing the nutrient content of rhizosphere soil may be the important reason for the effect of exogenous selenium on the growth of Atractylodes macrocephala in Xianfeng.