蚜虫危害与玉米果穗镰孢菌组成及毒素污染关系分析OA北大核心CSTPCD

[Objective]The objective of this study is to clarify the relationship between maize aphids damage and the occurrence of maize ear rot and the level of mycotoxin pollution in maize kernels,and to provide a reference for establishing a comprehensive control system of maize ear rot and exploring the effective control technology of main Fusarium toxins.[Method]The 105 aphid-damaged maize ears were collected from 46 cities and counties in Jilin Province in 2021.Pathogenic fungi were isolated and identified using tissue isolation and molecular biology methods for aphids,bracts and kernels.The isolation frequency of different Fusarium species on each sample and the proportion of the same Fusarium number isolated from different sample combinations in aphid-infested samples were calculated.The distribution of pathogens in different regions of Jilin Province and the correlation between the species of Fusarium carried by aphids,bracts and kernels were analyzed.Additionally,ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)was employed to determine the presence of Fusarium toxin species and content of maize kernels with and without aphid infestation.The detection rate of fumonisin(FB),deoxynivalenol(DON)and zearalenone(ZEA)in samples exceeding the standard was calculated,and the effect of aphid damage on the toxin secretion of Fusarium in kernels was analyzed.[Result]Aphids,bracts and kernels from 105 ears were tested for the Fusarium,the infection rate of aphids was 57.14％,and that of bracts and kernels was 81.90％and 82.86％,respectively.A total of 1 394 Fusarium strains,including 16 pathogenic Fusarium species,were obtained through single spore isolation and purification.Among them,8,13 and 12 Fusarium species were isolated from aphids,bracts and kernels,respectively.The dominant Fusarium species on aphids,bracts and kernels were F.verticillioides and F.proliferatum.Three species including F andiyazi,F incarnatum and F.temperatum were detected for the first time on maize kernels in Jilin Province.The results of mycotoxin analysis revealed a higher incidence of positive mycotoxin contamination in aphid-damaged maize ears compared to aphid-undamaged ones.All maize samples exhibiting excessive mycotoxin content were damaged by aphids.The identification of corresponding mycotoxin-producing strains was possible in the majority of cases where mycotoxins were detected in aphid-damaged maize ears.[Conclusion]F.verticillioides and F.proliferatum were the dominant Fusarium species isolated from aphids,bracts and kernels.The main Fusarium species isolated from aphids,bracts and kernels on the same maize ear were the same.Aphid damage significantly increased toxin accumulation levels in maize kernels,and the type of toxin was highly correlated with the detection of Fusarium species.