Screening and Residue Characteristics Analysis of Efficient Control Agents for Typical Diseases of Polygonatum sibiricum

HAN Jie; WANG Qinghai; ZHENG Yufei; HU Jin; ZHU Wencheng; WANG Xiuguo; LIU Tong

doi:10.15933/j.cnki.1004-3268.2026.01.009

Abstract：Anthracnose and leaf spot are two common diseases affecting Polygonatum sibiricum(Huangjing),for which no highly effective and safe pesticides have been registered for control to date.To screen safe and efficient pesticides against these two diseases,this study first conducted indoor toxicity tests to investigate the inhibitory effects of different pesticides on the pathogens of P.sibiricum anthracnose and leaf spot,thereby selecting highly effective control agents.Subsequently,field efficacy trials were carried out to verify the control effects of the selected pesticides.For the screened high-efficiency pesticides,a rapid residue analysis method was established using the quick,easy,cheap,effective,rugged,and safe(QuEChERS)sample pretreatment technique combined with ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).Meanwhile,field residue trials were performed to clarify the residue characteristics of these pesticides in P.sibiricum.The results showed that trifloxystrobin,carbendazim,and azoxystrobin exhibited good inhibitory effects on the anthracnose pathogen,with half-maximal effective concentrations(EC50)of 0.127,0.429,and 1.061 mg/L,respectively.For the leaf spot pathogen,hexaconazole,propiconazole,difenoconazole,and carbendazim showed excellent inhibitory activities,with EC50 values of 0.759,0.968,1.657,and 1.716 mg/L,respectively.Field efficacy results indicated that 25%trifloxystrobin suspension concentrate and 250 g/L azoxystrobin suspension concentrate had good control effects on P.sibiricum anthracnose,with field control efficiencies of 87.6%and 86.3%,respectively.Additionally,25%hexaconazole suspension concentrate and 250 g/L propiconazole emulsifiable concentrate showed superior control effects on P.sibiricum leaf spot,with field control efficiencies of 93.2%and 90.2%,respectively.For the residue analysis,after extraction with acetonitrile,purification with octadecylsilane(C18),and detection by UPLC-MS/MS,the recoveries of trifloxystrobin,azoxystrobin,propiconazole,and hexaconazole in P.sibiricum samples ranged from 82.5%to 98.3%at three spiking levels(0.02,0.50,and 10 mg/kg),with relative standard deviations(RSD)of 2.4%to 4.2%.The linear correlation coefficients(r)were all>0.998,the limits of quantitation(LOQ)were 0.010-0.016 mg/kg,and the limits of detection(LOD)were 0.003-0.005 mg/kg.Residue trials of the four pesticides were conducted in four locations across major P.sibiricum producing areas in China for one year.The results showed that the final residue levels of the four agents in P.sibiricum were all below the quantification limit at 21 days and 28 days after the last application,indicating low residue levels.In conclusion,25%trifloxystrobin suspension concentrate and 250 g/L azoxystrobin suspension concentrate can effectively control P.sibiricum anthracnose,while 25%hexaconazole suspension concentrate and 250 g/L propiconazole emulsifiable concentrate are effective for P.sibiricum leaf spot control.These findings provide safe and efficient pesticide options for the management of typical diseases in P.sibiricum and hold great significance for promoting the sustainable development of the P.sibiricum industry.