Climate change will increase aflatoxin presence in US Corn

Abstract

The impacts of climate change on agricultural production are a global concern and have already begun to occur (1, 2), with major drivers including warmer temperatures and the occurrence of extreme weather events (3-8). An important dimension of the climate change-crop yield relationship that has often been overlooked in the empirical literature is the influence that warming temperatures can have on plant damage arriving through biotic channels, such as pest infestation or fungal infection (5). Aflatoxins are carcinogenic chemicals produced by the fungi Aspergillus flavus and A. parasiticus, which commonly infect food crops. Currently, in the United States, aflatoxin is a perennial contaminant in corn grown in the South, but rare in the Corn Belt and northern states. Climate change may expand aflatoxin’s geographical prevalence, however; because hot, dry summers promote aflatoxin accumulation. Here we model aflatoxin risk as a function of corn plant growth stages and weather to predict US regions with high aflatoxin risk in 2031-2040, based on sixteen climate change models. Our results suggest that over 89.5% of corn-growing counties in fifteen states, including the Corn Belt, will experience increased aflatoxin contamination in 2031-2040 compared to 2011-2020. Interestingly, the results are spatially heterogeneous and include several Southern counties expected to have lower aflatoxin risk, because the causative fungi become inactivated at very high temperatures.

The Role of Preharvest Natural Infection and Toxin Contamination in Food and Feed Safety in Maize, South-East Hungary, 2014–2021

“…As many hybrids had very low or high to very high toxin contamination under the same environmental conditions, it is clear that, without knowing the resistance classification of the hybrid, its toxin behavior can hardly be forecasted. The forecasts shows higher toxin contamination in the northern hemisphere [ 35 , 37 , 42 , 84 , 85 ]. As the differences in hybrid resistance are very large in artificial inoculation tests [ 48 , 52 , 53 ] and also at natural infection and contamination verify this hypothesis, the combination of the two test regimes can lead to a decrease in toxin contamination.…”

“…We should not forget that the forecasting refers to the preharvest toxin contamination. As A. flavus and F. verticillioides need a higher optimum temperature than the ruling weather conditions secured in middle and western Europe, warmer and dryer summer conditions will increase the risk of aflatoxin and fumonisin contamination [ 36 , 37 ]. The different forecasting models [ 35 , 38 , 39 , 40 , 41 , 42 ] do not consider the resistance of the hybrids but use only the increasing temperatures and other non-plant traits.…”

May phytophenolics alleviate aflatoxins-induced health challenges? A holistic insight on current landscape and future prospects

“…The emerging reports on the GCC demonstrated that GW has begun to occur but the empirical data on how GW might affect crops yield is markedly overlooked ( 62 ). Strategically, GW and GCC might alter the distribution of plant pests and diseases, resulted in a significant damage to crop production.…”

“…In this regard, Yu et al reported that global temperature modification has an impact on the prevalence of AFs contaminants ( 62 ). According to the given model for simulation of AFs occurrence based on corn phenology, it is believed that some corn grown US states will experience an increased level of AFs occurrence by 2031–2040 ( 62 ).…”

“…In this regard, Yu et al reported that global temperature modification has an impact on the prevalence of AFs contaminants ( 62 ). According to the given model for simulation of AFs occurrence based on corn phenology, it is believed that some corn grown US states will experience an increased level of AFs occurrence by 2031–2040 ( 62 ). On the contrary, this estimation also postulated that under elevated temperatures AFs might be inactivated, therefore, some the US counties might experience lower level of AFs occurrence ( 62 ).…”