1Department of Agronomy, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Nakhon Pathom 73140, Thailand.
2Department of Plant Science and Agricultural Resources, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002, Thailand.
3School of Crop Production Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.
4Crop Genetics and Breeding Research Unit, USDA/ARS, Coastal Plain Experiment Station, Tifton, Georgia 31793, USA.
Traits related to nitrogen fixation may be used as indirect selection criteria for aflatoxin resistance in peanut. The aim of this study was to investigate the relationship between N2 fixation traits and aflatoxin contamination in peanut under different drought conditions. Eleven peanut genotypes were evaluated under three water regimes for two seasons in the field. Data were observed on kernel infection by Aspergillus flavus, aflatoxin contamination, total nitrogen content, N2 fixation and its related traits viz. nodule number, nodule dry weight and nitrogenese activity. Drought stress reduced total nitrogen content and N2 fixation, but it increased kernel infection and aflatoxin contamination. Total nitrogen content, N2 fixation and its related traits had negative and significant effects on kernel infection and aflatoxin contamination especially under drought conditions. In addition, negative correlations between kernel infection and aflatoxin contamination with drought tolerance index (DTI) of N2 fixation traits were also found. The results indicated that the ability to maintain high N2 fixation under drought conditions of peanut genotypes can result in better resistance to aflatoxin contamination.