Yield and quality of Amaranthus hypochondriacus grain amaranth under drought and salinity at various phenological stages in southern Italy

BACKGROUND Several studies have shown that grain amaranth (Amaranthus spp.) is tolerant to abiotic stresses such as drought and salinity. Irrigation applied only during sensitive growth stages can stabilize yield and improve water use efficiency. Given the increasing frequency of salinity and drought stress in European countries and the scarcity of information on grain amaranth responses to combined salt and drought stress, an open field trial was carried out in Italy in order to evaluate the response of one accession of Amaranthus hypochondriacus to various irrigation strategies. RESULTS Grain amaranth yield components were not negatively affected either by different irrigation volumes or by irrigation time. Some differences in seed yield were caused by water quality; salinity significantly reduced seed yield. The combined effect of irrigation time and irrigation volume significantly influenced seed yield. The quality of amaranth seeds was preserved; no significant differences due to simple or combined stresses were found during the three-year field experiment. CONCLUSIONS The overall results from this study suggest that A. hypochondriacus can be cultivated in a more sustainable way compared to other protein crops, thus reducing water use and using saline water. It could be introduced to marginal European environments where traditional crops cannot be cultivated. (c) 2021 Society of Chemical Industry