Field evaluation of Amaranthus species for seed and biomass yields in southern Italy

Abstract

Amaranth is a crop with a potentially increasing cultivation area. Little information is available on amaranth cultivation in Mediterranean environments and in southern Italy. The aim of this study was to evaluate the agronomic traits and assess the grain and biomass yield responses of 11 genotypes belonging to 5 Amaranthus species, provided from the USDA-ARS, National Plant Germplasm System. There was wide diversity in agronomic traits among Amaranthus species and among genotypes within the same species. The accessions belonging to A. cruentus had the shortest growing cycle followed by A. hybridus, A. hypochondriacus, A. caudatus and, finally, A. hybrid that had the longest growing season. The A. cruentus accessions reached maturity more quickly than the other species. The total above-ground dry matter ranged from 15 to 23 t ha-1 with A. cruentus, A. hypochondriacus, and A. hybridus being the most productive. The stem plus branches dry matter was well correlated to the plant height (r2 = 0.75**). The tested amaranth genotypes showed appreciable biomass production that can thus be regarded as an interesting secondary product after seed harvesting. Grain yield and components varied among species and accessions. A. hypochondriacus showed the highest yield per plant (55.4 g) followed by five accessions belonging to A. cruentus and A. hybridus (26.4 g on average). Considering together their shorter growing season and their higher grain production, the five accessions belonging to A. cruentus species appear to be better adapted to Mediterranean environments and southern Italy as compared to the other species.