Changes in the levels of jasmonates and free polyamines induced by Na2SO4 and NaCl in roots and leaves of the halophyte Prosopis strombulifera

Abstract

Prosopis strombulifera, a common legume in high-salinity soils of Argentina, is a useful model for elucidation of salt tolerance mechanisms and specific biochemical pathways in halophytes, since its NaCl tolerance exceeds the limit described for most halophytic plants. We analyzed the effects of the increasing concentration of two main soil salts, Na2SO4 and NaCl, on growth parameters of P. strombulifera, chlorophyll levels, and content of jasmonates (JAs) and polyamines (PAs), which are key molecules involved in stress responses. P. strombulifera showed a halophytic response (growth promotion) to NaCl, but strong growth inhibition by iso-osmotic solutions of Na2SO4. Chlorophyll levels, number of leaves and leaf area were also differentially affected. An important finding was the partial alleviation of SO 2− 4toxicity by treatment with two-salt mixture. JAs are not directly involved in salt tolerance in this species since its levels decrease under all salt treatments. Beneficial effects of Putrescine (Put) accumulation in NaCl treated plants maybe inferred probably associated with the antioxidative defense system. Another novel finding is the accumulation of the uncommon PA cadaverine in roots under high Na2SO4, which may be related to SO 2− 4 toxicity.

Physiological responses of a halophytic shrub to salt stress by Na2SO4 and NaCl: oxidative damage and the role of polyphenols in antioxidant protection

“…Alternatively, this response maybe associated with the beneficial effects of putrescine accumulation in NaCl-treated plants (Reginato et al 2012) which has been proposed as an inductor of the antioxidative defence system (Verma and Mishra 2005). …”

Alterations of Endogenous Hormonal Levels in Plants under Drought and Salinity

“…Likewise, in the halophyte P. strombulifera different endogenous levels of JAs (JA, OPDA, 11-OH-JA and 12-OH-JA) in roots and leaves treated with distinct salt treatments were observed. The 12-OH-JA level was higher in leaves than in roots in both control and treated plants, and this response may be the result of an active hydroxylation pathway in leaves or transport of root-generated 12-OH-JA [43]. In this regard, the occurrence of biosynthetic pathway of octadecanoic and jasmonates in roots was determined previously in cultures of tomato hairy root by [38] (Figure 2).…”

Polyamines and legumes: Joint stories of stress, nitrogen fixation and environment

“…In NaCl-treated Prosopis strombulifera, Put accumulation was related to the antioxidant defense system in this species (Reginato et al, 2012). Also, GABA is an important intermediate involved in ROS scavenging under abiotic stress and has been proposed that it contributes to stress protection (Bouche and Fromm, 2004;Liu et al, 2011).…”