Throughout the world, aflatoxin contamination is considered one of the most serious food safety issues concerning health. Chronic problems with preharvest afiatoxin contamination occur in the southern US, and are part...Throughout the world, aflatoxin contamination is considered one of the most serious food safety issues concerning health. Chronic problems with preharvest afiatoxin contamination occur in the southern US, and are particularly troublesome in corn, peanut, cottonseed, and tree nuts. Drought stress is a major factor to contribute to preharvest afiatoxin contamination. Recent studies have demonstrated higher concentration of defense or stress-related proteins in corn kerners of resistant genotypes compared with susceptible genotypes, suggesting that preharvest field condition （drought or not drought） influences gene expression differently in different genotypes resulting in different levels of ＂end products＂： PR（pathogenesis-related） proteins in the mature kernels. Because of the complexity of Aspergillus-plant interactions, better understanding of the mechanisms of genetic resistance will be needed using genomics and proteomics for crop improvement. Genetic improvement of crop resistance to drought stress is one component and will provide a good perspective on the efficacy of control strategy. Proteomic comparisons of corn kernel proteins between resistant or susceptible genotypes to Aspergillus flavus infection have identified stress-related proteins along with antifungal proteins as associated with kernel resistance. Gene expression studies in developing corn kernels are in agreement with the proteomic studies that defense-related genes could be upregulated or downregulated by abiotic stresses.展开更多
文摘Throughout the world, aflatoxin contamination is considered one of the most serious food safety issues concerning health. Chronic problems with preharvest afiatoxin contamination occur in the southern US, and are particularly troublesome in corn, peanut, cottonseed, and tree nuts. Drought stress is a major factor to contribute to preharvest afiatoxin contamination. Recent studies have demonstrated higher concentration of defense or stress-related proteins in corn kerners of resistant genotypes compared with susceptible genotypes, suggesting that preharvest field condition （drought or not drought） influences gene expression differently in different genotypes resulting in different levels of ＂end products＂： PR（pathogenesis-related） proteins in the mature kernels. Because of the complexity of Aspergillus-plant interactions, better understanding of the mechanisms of genetic resistance will be needed using genomics and proteomics for crop improvement. Genetic improvement of crop resistance to drought stress is one component and will provide a good perspective on the efficacy of control strategy. Proteomic comparisons of corn kernel proteins between resistant or susceptible genotypes to Aspergillus flavus infection have identified stress-related proteins along with antifungal proteins as associated with kernel resistance. Gene expression studies in developing corn kernels are in agreement with the proteomic studies that defense-related genes could be upregulated or downregulated by abiotic stresses.
