Acta Physiologiae Plantarum

, Volume 33, Issue 3, pp 935–942

Effect of salinity on germination, phytase activity and phytate content in lettuce seedling

  • Nawel Nasri
  • Rym Kaddour
  • Mokded Rabhi
  • Claude Plassard
  • Mokhtar Lachaal
Original Paper

DOI: 10.1007/s11738-010-0625-4

Cite this article as:
Nasri, N., Kaddour, R., Rabhi, M. et al. Acta Physiol Plant (2011) 33: 935. doi:10.1007/s11738-010-0625-4

Abstract

Seeds of four lettuce (Lactuca sativa L.) varieties (Romaine, Augusta, Vista and Verte) differing in their salt sensitivity were sown at 0 (Control), 50, 100 and 150 mM NaCl. The final germination percentage decreased with the increasing salinity and was annulated at the highest salt concentration in Vista and Verte, the most sensitive varieties. However, in the less sensitive ones, Romaine and Augusta, it was slightly modified at 50 and 100 mM NaCl and then decreased by 50% compared with the control, at 150 mM. The effects of NaCl 100 mM on seedling growth, phytase activities, phytate and inorganic phosphorus contents were studied in Romaine and Vista showing different behaviours towards salinity. Radicle and hypocotyl length and fresh and dry weights were reduced by salt treatment in both varieties. In addition, radicle phytase activity exhibited an increase in Romaine (less sensitive) and a decrease in Vista (more sensitive). In hypocotyl, this activity showed no difference with the control in the two varieties. However, in cotyledons, and during early hours after germination, salinity decreased phytase activity in both varieties whereas in the later hours (72–96 h) this activity reached the value of the control in Romaine. The enhancement of phytase activity was concomitant with an increase in orthophosphate content and a decrease in phytate reserve. These results suggest that salt presence in the medium delays Pi remobilization from phytate stock, but stimulates assimilation of phosphorus more than its accumulation in the organs of the two lettuce varieties.

Keywords

GerminationLettucePhytasePhytateSalinity

Copyright information

© Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2010

Authors and Affiliations

  • Nawel Nasri
    • 1
  • Rym Kaddour
    • 1
  • Mokded Rabhi
    • 2
  • Claude Plassard
    • 3
  • Mokhtar Lachaal
    • 1
  1. 1.Physiologie et Biochimie de la Tolérance au Sel des Plantes, Faculté des Sciences de TunisCampus UniversitaireTunisTunisia
  2. 2.Laboratoire des Plantes Extrêmophiles (LPE)Centre de Biotechnologie de Borj-CédriaHammam-LifTunisia
  3. 3.Ecologie Fonctionnelle and Biogéochimie du SolUMR 1222, INRA/IRD/SupAgro MontpellierMontpellier Cedex 1France