12,000

We have over 12,000 students, from over 100 countries, within one of the safest campuses in the UK

93%

93% of Lancaster students go into work or further study within six months of graduating

Home > Research > Publications & Outputs > Hormonal changes during salinity-induced leaf s...
View graph of relations

« Back

Hormonal changes during salinity-induced leaf senescence in tomato (Solanum lycopersicum L.)

Research output: Contribution to journalJournal article

Published

  • Michel Edmond Ghanem
  • Alfonso Albacete
  • Cristina Martínez-Andújar
  • Manuel Acosta
  • M. Remedios Romero-Aranda
  • Ian C. Dodd
  • Stanley Lutts
  • Francisco Pérez-Alfocea
Journal publication date08/2008
JournalJournal of Experimental Botany
Journal number11
Volume59
Number of pages12
Pages3039-3050
Original languageEnglish

Abstract

Leaf senescence is one of the most limiting factors to plant productivity under salinity. Both the accumulation of specific toxic ions (e.g. Na+) and changes in leaf hormone relations are involved in the regulation of this process. Tomato plants (Solanum lycopersicum L. cv Moneymaker) were cultivated for 3 weeks under high salinity (100 mM NaCl) and leaf senescence-related parameters were studied during leaf development in relation to Na+ and K+ contents and changes in abscisic acid (ABA), cytokinins, the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), and the auxin indole-3-acetic acid (IAA). Na+ accumulated to a similar extent in both leaves 4 and 5 (numbering from the base of the plant) and more quickly during the third week, while concurrently K+ contents sharply decreased. However, photosystem II efficiency, measured as the Fv/Fm ratio, decreased from the second week of salinization in leaf 4 but only at the end of the third week in the younger leaf 5. In the prematurely senescent leaf 4, ABA content increased linearly while IAA strongly decreased with salinization time. Although zeatin (Z) levels were scarcely affected by salinity, zeatin-riboside (ZR) and the total cytokinin content (Z+ZR) progressively decreased by 50% from the imposition of the stress. ACC was the only hormonal compound that increased in leaf tissue coincident with the onset of oxidative damage and the decline in chlorophyll fluorescence, and prior to massive Na+ accumulation. Indeed, (Z+ZR) and ACC contents and their ratio (Z+ZR/ACC) were the hormonal parameters best correlated with the onset and progression of leaf senescence. The influence of different hormonal changes on salt-induced leaf senescence is discussed.

Bibliographic note

This is an electronic version of an article published in Journal of Experimental Botany, 59 (11), 2008, p. 3039-3050.