Germination behavior of phytoremediate species of saline edaphic environments

Abstract

The increase in the salinization processes of the soils is an important problem due to the conditioning for agriculture. In Argentina, a susceptible zone is found in the SE of the province of Córdoba. In the Humid Pampa, the main source of salts is the groundwater. In the field under study, marginal areas with the presence of salts on the surface are located. The objective of the work is to evaluate the degree of salinization of the environment and identify viable species for future phytoremediation, through the study of the germinative behavior of species tolerant to certain ranges of salinity. Soil and groundwater samples were taken in three sub-environments of the saline shallows. Electric conductivity (EC) in saturation paste and pH_{(1: 2.5)} in soil, pH and EC of groundwater were analyzed. Germination tests were carried out with groundwater, using species: Festuca arundinacea, Thynopyrum ponticum, Lolium multiflorum, Hordeum vulgare and Chenopodium quinoa. The soils presented slightly alkaline pH and EC>2 dS m^-1, reaching extreme values ​​of 20,9 dS m^-1on the surface; groundwater at 60 cm depth, CE 16,8dS m^-1. The germination capacity was greater than 80% for L. multiflorum, F. arundinacea and Ch. Quinoa; equal to 67% and 50% for H. vulgare and Th. Ponticum respectively. Germination delay was observed according to a gradient of saline concentrations. For the recovery of the environmentinvestigated a mixture of L. multiflorum, F. arundinaceaandTh. Ponticum could be used. In high salinity environments Ch. Quinoa shows promise as a food-producing species.