AGROTECNIO-CERCA Center, Food Technology Department, University of Lleida, Rovira Roure 191, 25198 Lleida, Spain.
AGROTECNIO-CERCA Center, Department of Crop and Forest Sciences, University of Lleida, Rovira Roure 191, 25198 Lleida, Spain.
Toxins (Basel). 2022 Sep 5;14(9):620. doi: 10.3390/toxins14090620.
Agronomic factors can affect mycotoxin contamination of maize, one of the most produced cereals. Maize is usually harvested at 18% moisture, but it is not microbiologically stable until it reaches 14% moisture at the drying plants. We studied how three agronomic factors (crop diversification, tillage system and nitrogen fertilization rate) can affect fungal and mycotoxin contamination (deoxynivalenol and fumonisins B and B) in maize at harvest. In addition, changes in maize during a simulated harvest-till-drying period were studied. DON content at harvest was higher for maize under intensive tillage than using direct drilling (2695 and 474 μg kg, respectively). We found two reasons for this: (i) soil crusting in intensive tillage plots caused the formation of pools of water that created high air humidity conditions, favouring the development of DON-producing moulds; (ii) the population of , an earthworm that would indirectly minimize fungal infection and mycotoxin production on maize kernels, is reduced in intensive tillage plots. Therefore, direct drilling is a better approach than intensive tillage for both preventing DON contamination and preserving soil quality. Concerning the simulated harvest-till-drying period, DON significantly increased between storage days 0 and 5. Water activity dropped on the 4th day, below the threshold for DON production (around 0.91). From our perspective, this study constitutes a step forward towards understanding the relationships between agronomic factors and mycotoxin contamination in maize, and towards improving food safety.
农艺因素会影响玉米的真菌毒素污染，玉米是产量最大的谷物之一。玉米通常在含水量为 18%时收获，但在干燥厂达到含水量 14%之前，其并不具有微生物稳定性。我们研究了三种农艺因素（作物多样化、耕作制度和氮肥施用量）如何在收获时影响玉米中的真菌和真菌毒素污染（脱氧雪腐镰刀菌烯醇和伏马菌素 B1 和 B2）。此外，还研究了在模拟收获-干燥期间玉米的变化。深耕玉米的脱氧雪腐镰刀菌烯醇含量高于直接播种（分别为 2695 和 474μg/kg）。造成这种情况的原因有两个：（i）深耕地块的土壤结皮导致形成水洼，从而形成高空气湿度条件，有利于产生脱氧雪腐镰刀菌烯醇的霉菌的发展；（ii）蚯蚓的数量减少，而蚯蚓会间接减少玉米穗上真菌的感染和真菌毒素的产生，深耕地块中的蚯蚓数量减少。因此，与深耕相比，直接播种是一种更好的方法，既能防止 DON 污染，又能保护土壤质量。关于模拟收获-干燥期，DON 在储存的第 0 天和第 5 天之间显著增加。第 4 天水分活度下降，低于脱氧雪腐镰刀菌烯醇生产的阈值（约 0.91）。从我们的角度来看，这项研究是朝着理解农艺因素与玉米真菌毒素污染之间的关系以及提高食品安全迈出的一步。
