Morphological, chemical and physiological characterization of Amaranthus spp. Seeds

Abstract

Amaranthus species have great potential for human food due to their nutritional and functional properties, but there are few phytotechnical studies with this crop, making its cultivation unfeasible. Aiming to encourage the production of these species, this study aimed to evaluate and distinguish the morphological, chemical and physiological characteristics of seeds of Amaranthus sp. (commercial species), A. viridis and A. hybridus. The experiments were performed in a completely randomized design, evaluating seeds in size classes (850, 600 and 425 µm) and characterizing them by image analysis using the GroundEye® system, near-infrared spectroscopy (NIR) and radiographic analysis. The first germination count, germination and germination speed index with and without KNO3 were performed to evaluate the physiological quality of seeds. The results were submitted to analysis of variance and the means compared by the Tukey test. Radiographic analysis showed that the seeds of the three studied species were filled in the size class of 600 and 850 µm, without dormancy, but the commercial species had higher germination speed. GroundEye® and NIR allowed distinguishing the three species according to their geometric characteristics, predominance of color and chemical components.

Nutritional and bioactive compounds of Amaranthus spp. in Brazil

“…In the past, some of these species were used in the feeding of rural populations, and, recently, its importance is restricted to the fact they are invasive plants. Sometimes, they can be found as food for small indigenous and quilombola populations, thus little known by the rest of the population being considered, in Brazil, as non-conventional vegetables (Ossani et al, 2020;Silva et al, 2018;Xavier et al, 2019).…”

“…Scientific studies aiming at the analysis of the nutritional potential of these species have proved that their leaves and grains present high levels of proteins, essential amino acids, carotenoids and minerals (Molina et al, 2018;Sarker & Oba, 2019;Silva et al, 2018;Sreelatha et al, 2012). The flour made out of these vegetables is an option for celiac people since it is gluten-free (Xavier et al, 2019). The use of their leaves has also been recommended for the treatment of various chronic degenerative disorders such as cancer, diabetes and heart diseases because of their antioxidant properties (Queiroz et al, 2009;Ramkisson et al, 2020).…”

Luz, giberelinas y profundidad de siembra inciden sobre la germinación de semillas de Amaranthus hybridus L.

“…Therefore, the objective was to evaluate the effect of light, gibberellins, and seed burying depth on seed germination of bledo. In the first experiment, four light conditions were evaluated (red, blue, without light and natural light (control)), in the second experiment the seeds were imbibed in different concentrations of gibberellic acid (0, 200, 400 and 800mg L -1 of GA3), and in the last experiment, 8 planting depths were evaluated (10,20,30,40,50,60, 70 or 80mm) using peat as a substrate. A higher percentage of seed germination in darkness was found, indicating that this species had negative photoblastic seeds.…”

“…Varias especies pertenecientes al género Amaranthus son exitosas como malezas, porque presentan metabolismo fotosintético C4 y altas tasas de crecimiento. Producen grandes cantidades de semilla en sistemas agrícolas (entre 37.000 y 600.000 semillas por planta), muchas de ellas presentan latencia y poseen alta habilidad para la dispersión de semillas por el viento (Assad et al 2017;Xavier et al 2019). Esta condición permite que permanezcan viables en bancos de semillas en el suelo, por un largo periodo de tiempo (Assad et al 2017;Xavier et al 2019).…”

“…Por tanto, el objetivo fue evaluar el efecto de la luz, de las giberelinas y la profundidad de la siembra sobre la germinación de semillas de bledo. En un primer experimento, se evaluaron cuatro tratamientos de luz (rojo, azul, sin luz y luz natural «testigo»); en el segundo, se imbibieron semillas en diferentes concentraciones de ácido giberélico (0, 200, 400 y 800mg L -1 de GA3) y, en un último experimento, se evaluaron ocho profundidades de siembra (10,20,30,40,50,60, 70 y 80mm), utilizando turba como sustrato. Se encontró mayor porcentaje de germinación en oscuridad, indicando que son semillas fotoblásticas negativas.…”