IMPORTANCE OF IONIC AND OSMOTIC COMPONENTS OF SALT STRESS ON THE GERMINATION OF FOUR QUINUA (Chenopodium quinoa Willd.) SELECTIONS

The influence of the components of saline stress (osmotic and ionic factors) were evaluated during the germination of four quinua (Chenopodium quinoa Willd.) selections in Chile, two collected in the arid northern highland region with saline soils (Amarilla and Roja) and the other two from the rainy southern region with non-saline soils (Hueque and Pucura). The seeds were treated with different saline concentrations (0, 0.2, 0.4, 0.8 and 1.2 M NaCl). Germination kinetics shows that the control treatments of the four selections reach 100% germination. With application of 0.4 M NaCl (LD50max) germination was reduced by 53% in the Amarilla selection and 89.9% in Hueque. The germination rate was lower for the seeds from non-saline areas, which reached germination after 22 h, compared to 10 h for Amarilla. By separating the salinity stress factors (osmotic and ionic), it is evident that they have different degrees of influence on quinua germination, according to each selection. Thus, the germination of Amarilla selection from the arid area was the least influenced by the ionic factor (27%), Pucura and Roja were more affected by the ionic factor (40% and 46% respectively), and Hueque, from the rainy area, was more affected by the osmotic factor, in which caused a 50% loss in germination.