The use of neutron tomography for the structural analysis of corn kernels

Abstract

Neutron tomography was studied as a technique for non-destructively analyzing the internal structure of dried corn kernels. The study had two goals: first, to determine if the analysis could identify well-known anatomical features of the kernels; and second, to determine if it could distinguish between different types and treatments of kernels. Specifically, kernels which were infected vs. uninfected with the aflatoxin-producing fungus Aspergillus flavus were analyzed. Two different varieties of corn were used: VA35 (susceptible to A. flavus infection) and GT-MAS:gk (resistant). It was found that many anatomical features of the kernels could be identified using neutron tomography, including the scutellum, endosperm, aleurone, pericarp, pedicel, coleorhizae, radical, plumule, and coleoptile. Furthermore, differences were detected between susceptible kernels that had been inoculated and those that had not. Infected kernels were found to have lower neutron attenuation in the scutellum and embryo regions, possibly caused by lower hydrogen concentrations due to fungal degradation. No systematic structural differences were detected between resistant inoculated and resistant uninoculated kernels, as expected. This study indicated that neutron tomography could be a useful technique for the structural analysis of corn, and possibly other grains or small biological objects.