北京市郊玉米质量安全风险因子及影响因素分析

以北京郊区10个农户的玉米种植地为研究对象,扦取种植期土壤样品、扬花期花穗样品、收获期及不同储藏时期的玉米样品,检测菌相、带菌量和真菌毒素等。结果表明,玉米产后整个自然晾晒储藏期间,储藏前期(产后一个月内)的发霉风险最高,其中镰刀菌属一直是优势菌群,其产生的毒素主要包括脱氧雪腐镰刀菌烯醇(DON)、玉米赤霉烯酮(ZEN)和伏马菌素(FB1、FB2),检出率分别为100%、95%和93%,且DON和ZEN在储藏期的超标率均大于40%,而其他毒素,如AFBs、OTA、ST、T-2、HT-2等均未检出。另外,采用高通量测序技术分析了土壤和花穗样品中真菌多样性与农艺因素的关系,发现,种植方式(清种/兼做)、灌溉情况、上季秸秆处理方式等因素会影响玉米植株污染真菌的种类和数量,进而导致玉米籽粒真菌毒素的污染水平出现差异。

Analysis of risk factors and influencing factors of corn quality and safety in suburbs of Beijing

Taking the corn plantation area of 10 farmers in the suburbs of Beijing as the research object, soil samples from the planting period, flower spike samples from the flowering period, corn samples from the harvest period and different storage periods were taken to detect the mycoflora, microbial contamination and the mycotoxins. The results show that during the whole post-harvest natural drying period of corn, the risk of mold formation is highest in the early storage period (within one month after harvest). Among them, Fusarium has always been the dominant flora, and the toxins produced by it mainly include deoxynivalenol (DON), Zearalenone (ZEN), and fumonisin (FB1, FB2), the detection rates were 100%, 95%, and 93%, respectively, and the over-standard rates of DON and ZEN during the storage period were greater than 40%, and other toxins such as AFBs, OTA, ST, T-2, and HT-2 were not detected. In addition, the high-throughput sequencing technology was used to analyze the relationship between fungal diversity and agronomic factors in soil and spike samples, and it was found that factors such as planting methods, irrigation conditions, and last season''s straw treatment methods could affect corn. The type and quantity of plant-contaminated fungi resulted in differences in the levels of corn kernel mycotoxins.