Physical integrity of endive and chicory seeds determined by automated analysis of radiographic images

Abstract

Seeds are commercialized in Brazil after rigorous quality control, which is performed by mandatory tests that are time consuming and frequently destructive. X-ray image analysis has been highlighted as it has the advantage of being fast, nondestructive, can be automated, and for some species, has high correlation with the physiological quality of the seeds. This study aimed to investigate the efficiency of the X-ray test, combined with digital image processing techniques, to evaluate the characteristics of the internal structures of endive (Cichorium endivia L.) and chicory (Cichorium intybus L.) seeds, as well as to relate these characteristics to the physical integrity and physiological potential of the seeds. Four commercial chicory seed lots and six commercial endive seed lots were submitted to the X-ray test and subsequent germination test. By visual analysis of the images, cracks, embryo malformation, and empty spaces in the seeds were identified. The seeds presented high physiological quality, which agrees with the data obtained in the radiographic image analysis. The physical parameters evaluated through image analysis inferred the seed integrity and seed filling. Although a low correlation between physical and physiological parameters was observed, the analysis of the radiographic images allowed the identification of seeds with low physical and physiological quality. Thus, X-ray analysis is efficient in evaluating the physical integrity of chicory and endive seeds and has the potential to infer their physiological quality.