Endogenous jasmonates and free polyamines in salinized seedlings of the halophyte Prosopis strombulifera.

REGINATO , MARIANA ANDREA; ABDALA, GUILLERMINA IRENE; RUIZ, OSCAR; MOSCHETI, ELSA; LUNA, MARÍA VIRGINIA

Córdoba

Congreso; Primer Congreso de la Red Argentina de Salinidad; 2009

Red Argentina de Salinidad

The aim of this work was to determine the effects of increasing concentrations of Na2SO4, NaCl and their iso-osmotic mixture on endogenous jasmonates (JAs) and free polyamines (PAs) levels in P. strombulifera seedlings. Seedlings were grown hydroponically in Hoagland?s solution with addition of salt pulses of Na2SO4, NaCl, and their mixture every 48 h until final Ψo= -1, -1.9 and -2.6 MPa were reached. HPLC-GC-MS-SIM was used to separate and quantify JAs and HPLC-FD for PAs. The JA precursor OPDA, JA and the JA derivatives (11-OH-JA and 12-OH-JA) were detected in P. strombulifera seedlings. The major compounds in roots were OPDA and JA, whereas in leaves OPDA and 12-OH-JA levels were higher, demonstrating the existence of specific JAs profiles according to the organ analyzed. Prosopis roots responded to high salinity by decreasing total JAs content, whereas in leaves, only high salinity diminished total JAs, principally Na2SO4 treatment. 12-OH-JA and 11-OH-JA were not affected by salinity. Free PAs levels were 5 fold higher in leaves than in roots. Putrescine and 1-3 diaminopropane (Dap) were the most abundant PAs in leaves, and putrescine and spermidine in roots. Dap (catabolite) increased in all salt treatments. Cadaverine (uncommon PA) was found only in roots and increased in response to high Na2SO4. Endogenous JAs levels seem to play no role in salt tolerance in this species. A different but active pattern of PA metabolism was found in leaves and roots; the uncommon PA Cadaverine is a novel result maybe related to non tolerance to/toxicity of sulfate anion.