Considering the wide range of peanut cultivation in China with
diversified climates, aflatoxin contamination of peanuts is a significant
issue. However, the specific relationship between preharvest
weather data and aflatoxin contents of pre-harvest peanuts
has not been studied in China and it was investigated in this
paper for first time. It presented the data and the results of aflatoxin
contamination of peanuts in four representative provinces under
different agro-environments in China in the years 2010e2013. The
natural occurrence of aflatoxins varies according to localities and
years. The optimal temperature in favor of aflatoxin contamination
in peanuts would rise along with the decrease of the latitude.
Among the 2494 peanut samples in the four provinces, the percentages
of aflatoxin-positive samples and mean contents of aflatoxins
and the percentages of non-compliant samples were highest
in Sichuan and lowest in Liaoning. The aflatoxin B1 content in
peanuts at harvest was closely related to climatic conditions before
harvest. When the mean temperature was close to 23 C, minimum
temperature was close to 20 C, and maximum temperature was
close to 29 C under drought stress, the level of aflatoxin contamination
was high. When the mean temperature was 15e28 C,
minimum temperature was 13e26 C, and maximum temperature
was 20e33 C under drought stress, the content of aflatoxin B1
would go beyond the limit of 20 mg/kg. The results of this survey
provided support for the establishment of a large-scale predictive
model suitable for China. Most importantly, it provided information
for the local government and farmers to take proper measurements
to reduce aflatoxin production, for example, adjusting the cultivation
period and implementing irrigation when the weather conditions
may result in severe aflatoxin contamination. In addition, the
results of this study were affected by different levels of resistance to
aflatoxin in different peanut varieties, irrigation situations, soil
types, planting patterns, and so on. There is further work to do to
establish a high precision model of predicting aflatoxin contamination
risks of peanuts in China.