Evaluating management strategies with crop modeling for salinity stress mitigation in quinoa: A case study from Laayoune, Morocco

Abstract

Quinoa, known for its high nutritional value and resilience to saline and drought conditions, is a dietary staple in arid regions like Morocco, where agriculture relies heavily on irrigation with variable salinity levels. A previous study in Laayoune, southern Morocco, pointed out that overirrigation during the germination and seedling stages results in salt accumulation in the topsoil and exacerbates salinity stress. In the current study, we assessed management scenarios (mulch, irrigation strategies) limiting soil evaporation and mitigating salinity stress in the Laayoune region. Simulations indicate that reducing irrigation frequency and employing mulch, decreases soil evaporation and soil salt concentration, improving yield. Quinoa is most sensitive to salinity stress during germination and seedling stages, whereas its sensitivity to drought is highest during flowering and seed filling. Mitigating stress mainly in those periods with the proposed management practices, allows to reduce irrigation water use and enable the use of higher-salinity irrigation water without significantly affecting yield. These findings offer practical insights for cultivating crops using saline irrigation water in arid regions, and provides a basis for field-scale testing. • Less frequent, but larger irrigation events reduces soil evaporation and promotes salt leaching in arid regions • Irrigation aligned with quinoa crop development improves saline water-use efficiency • Mulching boosts soil moisture and limits root zone salinity leading to higher and more stable quinoa yields