Evaluation of Cedrela fissilis Vell. seeds with color heteromorphism using near-infrared spectroscopy and their relationship with physiological quality

ABSTRACT:

Cedrela fissilis Vell., commonly known as cedro-rosa, is a tree species native to Brazil, with ecological and economic relevance, that exhibits seed heteromorphism associated with seed coat color. In this study, the classification of light- and dark-colored seeds using near-infrared (NIR) spectroscopy and its relationship with physiological quality was evaluated. NIR spectra were obtained, reserve compounds were quantified, and germination and vigor tests were conducted. The NIR spectra, collected from individual seeds, were preprocessed and used to develop classification models based on the Partial Least Squares - Discriminant Analysis (PLS-DA) method. The physiological and biochemical composition data were analyzed using Student’s t-test. Dark seeds showed higher thousand-seed weight, total protein content, as well as greater germination and vigor. Light seeds exhibited higher levels of reducing sugars, suggesting a lower degree of maturity or the onset of deterioration. NIR spectroscopy demonstrated high accuracy in distinguishing between light and dark seeds, especially in the spectral band near 1938 nm, whose relevance may be mainly associated with variations in total protein content. Seed coat color proved to be a reliable indicator of the physiological quality of C. fissilis seeds.

Index terms:
Cedro-rosa; chemometrics; NIR spectroscopy; seed germination and vigor