Espectroscopia de infravermelho e nível de deterioração de sementes de Nicotiana tabacum L.

Abstract

The development of methodologies to evaluate the seed quality is essential for programs of seed quality control, because they are enable the for distinction of seed lots with different vigor levels. The tobacco (Nicotiana tabacum) is commonly used like a model plant for genetic or physiological studies related to abiotic stess tolerance, mainly. However, it is known little about the possibility of the use of more precise procedures to evaluate the physiological quality of tobacco seeds in the commercial production. The near infrared spectroscopy (NIR) is standing out as a non-destructive method and has potential to replace or to complement the ordinary methodologies of laboratorial analysis to guarantee quality. The objective of this work was to verify the efficiency of the use of NIR to identify levels of deterioration in different lots of tobacco seeds. Five seed lots of cultivar CSC 100 “amarelinho” group were used and each one was submitted to artificial aging for 0, 24, 48, 72 e 96 hours and were realized the following tests and determinations: seed moisture content, germination and emergence test, health test and NIR spectral analysis. The experiment designed used was the completely randomized design in a factorial scheme 5 x 5. To analyze the spectra obtained was used the Partial Least Squares Discriminant Analysis (PLS-DA). The deterioration and the modification caused by the artificial aging in tobacco seeds influenced differently the results obtained through NIR. There is a relationship between levels of deterioration of tobacco seeds artificially aged evaluated by physiological parameters and the intensity of the absorbance obtained by spectral analysis (NIR) at a wavelength 10000-5000 cm-1.