Quinoa : An Alternative Crop for Saline Soils in the Andes

Abstract

Salt tolerance mechanisms were studied in two varieties of quinoa (Chenopodium quinoa Willd.), and in one variety of amaranth (Amaranthus caudatus L.). The experiment was conducted in pots in a greenhouse at CIP, Lima, Peru. The amaranth demonstrated very little ability for regulation of leaf water potential and stomatal conductivity, and the plants died at high salinity levels. Quinoa behaved as a facultative halophyte, accumulating salt ions in the tissue. This mechanism adjusted leaf water potential, enabling the plants to maintain cell turgor and limit transpiration under saline conditions. The accumulation of salt indicates that quinoa may be used to clean saltcontaminated soils. The characters most sensitive to salinity were stomatal conductance, leaf area, and plant height. Therefore, screening for only minor reduction in, for instance, plant height may be a means of identifying varieties for saline soils.