Salicylic acid differently impacts ethylene and polyamine synthesis in the glycophyte Solanum lycopersicum and the wild-related halophyte Solanum chilense exposed to mild salt stress.
This study aimed to determine the effects of exogenous application of salicylic acid (SA) on the toxic effects of salt in relation to ethylene and polyamine synthesis, and to correlate these traits with the expression of genes involved in ethylene and polyamine metabolism in two tomato species differing in their sensitivity to salt stress, Solanum lycopersicum cv Ailsa Craig and its wild salt-resistant relative Solanum chilense. In S. chilense, treatment with 125 mM NaCl improved plant growth, increased production of ethylene, endogenous salicylic acid and spermine. The production was related to a modification of expression of genes involved in ethylene and polyamine metabolism. In contrast, salinity decreased plant growth in S. lycopersicum without affecting endogenous ethylene, salicylic or polyamine concentrations. Exogenous application of salicylic acid at 0.01 mM enhanced shoot growth in both species and affected ethylene and polyamine production in S. chilense. Concomitant application of NaCl and salicylic acid improved osmotic adjustment, thus suggesting that salt and SA may act in synergy on osmolyte synthesis. However, the beneficial impact of exogenous application of salicylic acid was mitigated by salt stress since NaCl impaired endogenous SA accumulation in the shoot and salicylic acid did not improve plant growth in salt-treated plants. Our results thus revealed that both species respond differently to salinity and that salicylic acid, ethylene and polyamine metabolisms are involved in salt resistance in S. chilense.
Groupe de Recherche en Physiologie Végétale (GRPV), Earth and Life Institute - Agronomy (ELI-A), Université Catholique de Louvain, Louvain-la-Neuve, Belgium.|Laboratoire d'Ecologie Végétale, Faculté des Sciences, Université de Tunis El Manar, Tunis, Tunisia.
Emna
E
Gharbi
Laboratorio de Fisiología Vegetal, Instituto de Investigaciones Agropecuarias (INIA - La Cruz), La Cruz, Chile.
Juan-Pablo
JP
Martínez
Laboratoire d'Ecologie Végétale, Faculté des Sciences, Université de Tunis El Manar, Tunis, Tunisia.
Hela
H
Benahmed
Unité de Chimie Générale et Organique, Faculté des Sciences Agronomiques, Université de Liège, Liège, Belgium.
Marie-Laure
ML
Fauconnier
Groupe de Recherche en Physiologie Végétale (GRPV), Earth and Life Institute - Agronomy (ELI-A), Université Catholique de Louvain, Louvain-la-Neuve, Belgium. stanley.lutts@uclouvain.be.
Stanley
S
Lutts
Groupe de Recherche en Physiologie Végétale (GRPV), Earth and Life Institute - Agronomy (ELI-A), Université Catholique de Louvain, Louvain-la-Neuve, Belgium.
Muriel
M
Quinet
D005030:Ethylenes / Q000378:metabolism; D018551:Solanum lycopersicum / Q000187:drug effects / Q000502:physiology*; D009995:Osmosis; D010937:Plant Growth Regulators / Q000378:metabolism*; D011073:Polyamines / Q000378:metabolism*; D020156:Salicylic Acid / Q000378:metabolism*; D054712:Salinity; D055051:Salt-Tolerant Plants; D012965:Sodium Chloride / Q000494:pharmacology*; D032322:Solanum / Q000187:drug effects / Q000502:physiology*; D013312:Stress, Physiological
D005030:Ethylenes; D010937:Plant Growth Regulators; D011073:Polyamines; D012965:Sodium Chloride; C036216:ethylene; D020156:Salicylic Acid