Análise do potencial da técnica de biospeckle laser aplicado como ensaio não destrutivo para a avaliação de germinação de sementes agrícolas

Abstract

Agricultural seeds are of great importance to Brazilian agribusiness, as well as to the country’s economy and food security. In this context, soybean (Glycine max) and corn (Zea mays) crops stand out. Therefore, ensuring the planting of viable seeds is essential for good productivity. The high quality of the seeds used directly contributes to good production; thus, the methods used to evaluate seed viability represent a crucial step for the success of agribusiness in Brazil and for ensuring that germination quality is guaranteed for producers. In this regard, there are tests aimed at verifying the germinative viability of seeds, such as the standard germination test and the tetrazolium test. However, these tests can be destructive and are performed using samples, which may increase the imprecision of the results. Thus, a method for analyzing germination quality that is non-destructive, rapid, and capable of analyzing seeds individually is desirable. This undergraduate thesis aimed to analyze the BioSpeckle Laser technique, whose desired characteristics mentioned above may be achieved. This technique uses a laser that scatters or transmits a beam of light. The reflection of the laser light on the plant tissue was collected by a CCD camera and stored for processing, which was performed using a specific algorithm. Quantitative data were obtained through the “Moment of Inertia” (MI) determination technique for image processing, as it makes it possible to analyze the biological activity of the material through the determination of the MI index and to identif abnormalities in cell functioning, thus verifying the viability and quality of a seed. The test specimens consisted of soybean and corn seeds that were stored under ideal and non-ideal conditions, causing variations in germination quality among the seeds. The results obtained were analyzed using graphs and statistical tests, such as analysis of variance (ANOVA). As a result, it was concluded that the differentiation in the seed storage method generated significant differences for the study, and the BioSpeckle Laser technique proved capable of identifying differences in the germinative potential of soybean and corn seeds.