A novel hyperspectral imaging system for whole corn ear analysis and aflaxtoxin detection

Authors: Yao, Haibo; HRUSKA, ZUZANA - Mississippi State University; KINCAID, RUSSELL - Mississippi State University; Huang, Yanbo; Rajasekaran, Kanniah; Jeffers, Daniel; Babiker, Ebrahiem

Submitted to: Journal of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/5/2025
Publication Date: 10/1/2025
Citation: Yao, H., Hruska, Z., Kincaid, R., Huang, Y., Rajasekaran, K., Jeffers, D., Babiker, E.M. 2025. A novel hyperspectral imaging system for whole corn ear analysis and aflaxtoxin detection. Journal of the ASABE. 68:791-800. https://doi.org/10.13031/ja.16447.
DOI: https://doi.org/10.13031/ja.16447

Interpretive Summary: Corn is the number one crop in the United States. The US is also the largest corn producer in the world, representing one-third of world production. In corn production, inspection of whole corn ears is important during preharvest scouting. This paper developed a novel hyperspectral imaging system for whole corn ear imaging and aflatoxin contamination detection. This research demonstrates that the new development could be a valuable and non-invasive approach for aflatoxin detection in whole corn ears.

Technical Abstract: This paper reports research on aflatoxin contamination detection in whole corn ears. The research developed a novel hyperspectral imaging system for whole corn ear imaging. The hyperspectral imaging system employs pushbroom line-scanning with a rotational stage, enabling the acquisition of a flattened, two-dimensional spectral image of the entire ear surface. Field experiments were conducted to obtain corn ears contaminated with aflatoxin. Specifically, four treatments were implemented including Control, Control Pierced, 25% Aspergillus flavus (AF13) inoculation, and 100% AF13 inoculation. 50 ears were harvested for each treatment for the analysis. Each ear was imaged under ultraviolet light (365 nm) for fluorescence hyperspectral data acquisition and subsequently analyzed chemically for aflatoxin content. Image analysis was based on a rapid spectral method, Normalized Fluorescence Difference Index (NDFI), using wavelengths at 537 and 437 nm for NDFI calculations. It was found that both inoculated treatments were severely contaminated with aflatoxin, with the 25% inoculation treatment having the highest aflatoxin content. A fluorescence peak shift was observed for the contaminated pixels. The clean control pixels have a fluorescence peak of 478 nm. The fluorescence peaks for the contaminated pixels are 506 - 516 nm. When using 20 ppb (parts per billion) as a threshold for aflatoxin detection, the overall detection accuracy reached 80%, with the Control Pierced group achieving the highest accuracy of 86%. Notably, the study found no direct correlation between the number of detected “hot pixels” and measured aflatoxin concentration. This research is the first to report on the use of the kernel crown fluorescence for aflatoxin detection and highlights the potential of whole-ear hyperspectral imaging for non-invasive contamination screening and phenotypical trait analysis in corn breeding.