Comparison between radiological and tomographic methods for evaluation of mechanical damage in seeds

Abstract

Mechanical damages are considered one of the main factors that may adversely affect the seed physiological potential. A significant advancement of knowledge on mechanical damages evaluation in seeds occurred in the late 1990s with the application of X-ray as a nondestructive procedure, allowing to relate the internal injuries occurrence with germination and vigor. However, in some cases the 2D images generated in the radiographic analysis are not sufficient to effectively identify injuries associated with loss of germination, probably for preclude an accurate analysis of the fractures depth. The normal seedlings development even when occurring injuries on the embryonic axis is a major event in the literature that reinforces this limitation of the X-ray test. The application of tomographic methods such as X-ray computed microtomography (microCT) and magnetic resonance (MR), to assess the mechanical damages occurrence in seed using a three-dimensional (3D) scale may help to clarify these subjects. The purpose of this research is to study corn and soybean seeds, with the objectives: (i) optimize the image acquisition parameters through microCT and MR for adequate visualization of the internal seed morphology, (ii) to analyze comparatively the X-ray, microCT and MR images of each seed and to establish a relationship with the results of the germination test. (AU)