Genotypic difference in physico-chemical grain composition of three species of grain amaranth selected for the Brazilian Savannah

Abstract

Seventeen genotypes, representing three species of grain amaranth, were analyzed for physico-chemical components. These genotypes are considered outstanding in terms of agronomical performance, necessitating an understanding of protein, lipids, fiber, and carbohydrate content. It has been demonstrated that A. cruentus, A. hypochondriacus, and A. caudatus differ in the content and properties of these compounds. Based on field experiments conducted in the Brazilian Savannahs, these genotypes were initially tested for germination and vigor after 12 years of storage under low moisture conditions at 10°C in air-tight plastic bags. Assuming that the physico-chemical characteristics were maintained, as indicated by an average 80% germination rate, samples of amaranth seeds were milled and used for analysis. The results indicate protein content below expectations, with the highest values above 14g per 100g, while lipids, fiber, and carbohydrates are within the expected range. The possible factors to explain these results are related to the cultivation environment, although genotypic differences are also significant. Additional testing with broad-based selected lines is necessary to improve selection for both agronomic and physico-chemical composition. The present results suggest that efforts should be concentrated on A. cruentus and A. hypochondriacus.