Exploring the Advancements in Non-Destructive Testing Techniques for Assessing Plant Seed Viability

During the past decades, imaging and spectroscopic techniques with wide applications have rapidly developed for determining the quality of agricultural products in a non-destructive manner. As a synergy between spectroscopy and imaging technologies, spectral imaging methods have emerged to deal with quality assessment problems along with ideas with effective and practical applications to food and agriculture industries. Agricultural commercialization has prompted the need to determine the quality of agricultural inputs, especially seeds, in order to optimize production and increase economic returns. Seed viability is a critical consideration to ensure high yields. Most of the time, farmers suffer losses after a significant percentage of seeds fail to germinate after planting. Seed viability is very important in the quality characteristics of seeds that reflect the potential of seed germination, and it is necessary to have a quick and effective method to determine the quality and state of germination and seed viability prior to cultivation and sale and during planting. Some research based on spectrum and/or image processing and analysis have been investigated to verify the external and internal quality of seed types. Spectroscopy is used to examine and measure the spectra produced by the interaction of matter with electromagnetic radiation or the radiation emitted from it, and the near-infrared (NIR) technique is one of these techniques for non-destructive tests of samples. Hyperspectral and multispectral imaging is another non-destructive technique that is used to obtain spectral and spatial information about materials, including seeds. The use of Raman spectroscopy is an alternative non-destructive method that is used to check seed viability with non-destructive laser radiation. Thermal imaging is a technique for converting the invisible radiation pattern of an object into visible images and extracting and analyzing the properties of the material without any contact. And finally, the use of electromagnetic waves with different wavelengths from 1 to 100 nm and energy of approximately 0.12 to 12-kilo electron volts. The low power penetration of these waves and their ability to detect internal changes in density makes soft X-rays suitable for use in evaluating agricultural products. This article refers to the comparative introduction and application of emerging techniques in the study of seed viability, including the near-infrared spectroscopy, hyperspectral and multispectral imaging, Raman spectroscopy, infrared thermography, and soft X-ray imaging.