Growth and Element Allocation in Tissues of Inula viscosa in Sodic-saline Conditions: A Candidate for Programs of Desertification Control

ABSTRACT

Sticky fleabane, Inula viscosa, a wild perennial Asteracea widespread in the Mediterranean area, is characterized by high tolerance to water deficiency. In this study, plants of I. viscosa obtained from seedlings were grown in a controlled environment and irrigated from transplanting to flowering with salinized water at seven different NaCl concentrations (ECi = 0.5 to 52.1 dS m⁻¹), in order to evaluate the salinity tolerance and the ion content (Na, Cl, N, P, K, Ca and Mg, as mg kg⁻¹ of dry weight) within plant tissues (roots, basal stems, medium stems, apical stems, lateral shoots, basal and apical leaves). Data obtained showed for I. viscosa a marked tolerance to salt stress. A K/Na concentration ratio of 0.1 was in the tissues of the basal leaves, suggesting a mechanism of Na exclusion from the younger leaves and the apical stems. The results in the first growing year indicate that I. viscosa can grow and flower in saline conditions up to ECi = 52.1 dS m⁻¹, even if it shows a marked reduction of fresh and dry weight; although Inula viscosa cannot be defined an halophyte plant as Inula crithmoides, it can be considered suitable for programs of desertification control, considering its high fresh biomass production also in high salinity conditions.

Keywords:

• saline agriculture
• ion adsorption
• ECi
• salt-tolerant plants

Notes

*significant at P ≤ 0.05.

***significant at P ≤ 0.01.

Relationship tested by regression analysis between ECi values and responses of each character.