Regulación de la tolerancia a la salinidad y a la sequía en especies del Salsola L., en los desiertos áridos de los Emiratos Árabes Unidos

The study assessed responses of some morphological, physiological and biochemical attributes to salinity effects of S. drummondii adult plants from saline and non-saline habitats, in addition to young potted plants treated with different NaCl levels in the laboratory. There was insignificant difference in many of the studied attributes between plants grown in saline and those grown in non-saline habitats; e.g. leaf fresh and dry weights, leaf succulence, concentrations of some essential elements and some antioxidants. S. drummondii seedlings grew very well in up to 500 mM NaCl under the lab conditions, and associated with antioxidants increase with increasing NaCl up to 800 mM NaCl. Transcriptome analysis for salt tolerance in S. drummondii identified 17361 differentially expressed genes; 1283 (7.3%) of them can be assembled into nine functional categories which may hold specific biological functions in salt tolerance mechanisms. Fecha de lectura de Tesis Doctoral: 6 mayo 2020Drought and salt stresses are among the important factors limiting plant growth and distribution in the United Arab Emirates (UAE) deserts. The current study assessed the impacts of habitat origin (saline and non-saline habitats), temperature, and light on drought and salinity tolerances during germination of Salsola drummondii Ulbr., a habitat-indifferent halophyte. Drought tolerance was also assessed for S. imbricata Forssk. Seeds treated with different concentrations of sodium chloride (NaCl) (0 to 1000 mM NaCl) for salinity analysis, and polyethylene glycol (0 to -1.5 MPa for S. drummondii and 0 to -2.4 MPa for S. imbricata) for drought analysis, were incubated at three temperatures and two light different regimes. Seeds of S. drummondii from the two habitats differed in dormancy, germination speed, and responses to light and temperature, which could be considered as environmental cues to determine the proper space and time of germination. The two Salsola L., species germinated better at the lower than at higher thermoperiods. Seeds of S. imbricata tolerated higher drought stress than S. drummondii.Tesis realizada en el Departamento de Botánica y Fisiología Vegetal de la Universidad de Málaga, en el ámbito de las actividades del Grupo de Investigación RNM 115 “BIODIVERSIDAD, CONSERVACION Y RECURSOS VEGETALES” -del Plan Andaluz de Investigación, Desarrollo e Innovación de la Junta de Andalucía-. El presente trabajo ha estado financiado por los siguientes proyectos entre la Universidad de Malaga, UMA y la Universidad de Sharjah, UoS: Transcriptomics and Metabolics analysis to Reveal Salt and Heat Stress Related Genes, Phytohormones and Osmolytes in Facultative Halophytes plant of the UAE (2017-2019). UMA 1602145041-P. Otra parte de la investigacion ha sido realizada en el Departamento de Biologia Aplicada de la Universidad de Sharjah. Sharjah, Emiratos Arabes Unidos (UAE)