Characterization of the response of in vitro cultured Myrtus communis L. plants to high concentrations of NaCl.
Effect of salt stress was examined in in vitro shoot cultures of Myrtus communis L. a species of the Mediterranean maquis. To determine the effects of high salt concentrations on myrtle plantlets and contribute toward understanding the mechanisms adopted from this species to counteract soil salinity, in vitro rooted shoots were transferred to a liquid culture medium containing 0, 125 or 250 mM NaCl for 30 days. After 15 and 30 days of in vitro culture, shoot and root growth, chlorosis and necrosis extension, chlorophylls, carotenoids, proline, arginine, cysteine and total sugars content, as well as guaiacol peroxidase (G-POD, EC 1.11.1.7) and ascorbate peroxidase (APX, EC 1.11.1.11) activities were determined. In treated plants shoot and root growth, as well as chlorophyll content, significantly decreased, while carotenoids content was not affected by the NaCl treatment. Among osmolytes, proline did not significantly increase, arginine and cysteine decreased, while total sugars were found to be higher in the treated plants than in the control. Enhancement of G-POD and APX activities was positively related to increasing salt concentrations in the culture media, regardless of the exposure time. Salt-treated plants did not show significant changes in lipid peroxidation or DNA fragmentation after 30 days salt treatment, regardless of the NaCl concentrations applied. The results represent a contribution towards understanding the mechanisms adopted by this species to high salinity.
Department of Biology, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133 Rome, Italy.
P
P
Di Cori
S
S
Lucioli
A
A
Frattarelli
P
P
Nota
E
E
Tel-Or
E
E
Benyamini
H
H
Gottlieb
E
E
Caboni
C
C
Forni
D001120:Arginine / Q000378:metabolism; D060387:Ascorbate Peroxidases / Q000378:metabolism*; D050260:Carbohydrate Metabolism / Q000187:drug effects; D002338:Carotenoids / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry; D003545:Cysteine / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D015227:Lipid Peroxidation / Q000187:drug effects; D031651:Myrtus / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D018384:Oxidative Stress; D009195:Peroxidase / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D011392:Proline / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D054712:Salinity; D055049:Salt Tolerance; D012965:Sodium Chloride / Q000378:metabolism / Q000494:pharmacology*; D013312:Stress, Physiological; D013482:Superoxide Dismutase / Q000378:metabolism
D003470:Culture Media; D017382:Reactive Oxygen Species; D002734:Chlorophyll; D002338:Carotenoids; D012965:Sodium Chloride; D001120:Arginine; D011392:Proline; C121048:guaiacol peroxidase; D060387:Ascorbate Peroxidases; D009195:Peroxidase; D013482:Superoxide Dismutase; D003545:Cysteine
6-benzylaminopurine; APX; BAP; Enzymatic and non-enzymatic antioxidants; G-POD; IBA; In vitro culture; LN; MDA; MKI; McKinney Index; Myrtle; PCD; ROS; Salt stress; ascorbate peroxidase; f.w.; fresh weight; guaiacol peroxidase; indole-3-butyric acid; liquid nitrogen; malondialdehyde; programmed cell death; reactive oxygen species