|GALLEGO-TEVAR, BLANCA - University Of Seville|
|PEINADO-TORRUBIA, PROCOPIO - Instituto De Recursos Naturales Y Agrobiologia De Sevilla (IRNAS-CSIC)|
|ALVAREZ-MORALES, MARIA ROSARIO - University Of Seville|
|CASTILLO, JESUS - University Of Seville|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/17/2019
Publication Date: 6/14/2019
Citation: Gallego-Tevar, B., Peinado-Torrubia, P., Alvarez-Morales, M., Grewell, B.J., Castillo, J.M. 2019. Combined effects of salinity and inundation on phosphoenolpyruvate carboxylase activity in two Spartina species and their hybrid. Meeting Abstract. Abstract.
Technical Abstract: Interspecific hybridization and polyploidy are linked to improved invasiveness of plant species in relation to higher competitiveness, tolerance to abiotic factors and phenotypic plasticity. However, little is known about their effect on plant enzymatic activities in response to environmental stress factors. Polyploid plant taxa resulting from natural hybridization represent an opportunity for the study of these evolutionary mechanisms in situ. Sea Level Rise (SLR) associated with climate change is expected to intensify the period of permanent submersion and salinity in coastal salt marshes. In this context, the study of the responses of native and invasive halophytic plant species to SLR is essential to maintain their conservation status. With this aim, we assessed the effect of inundation depth and salinity on phosphoenolpyruvate carboxylase (PEPC) for three species of the polyploid cordgrass taxa of invasive Spartina (S. densiflora (2n = 7x = 70); S. foliosa (2n = 6x = 60) native to Califonria, and the hybrid S. densiflora x foliosa (2n = 6.5x = 65) in a greenhouse experiment. PEPC is the key enzyme involved in photosynthetic C4 metabolism of these cordgrasses. We also measured oxidative stress by recording malondialdehyde (MDA) and free proline contents in flag leaves of the three taxa. We found a general improvement of PEPC phosphorylation in vivo in the Spartina taxa at deep flooding conditions. A different behaviour for S. densiflora in comparison with another ecotype from SW Iberian Peninsula was observed. These results pointed out the relevance of heterosis and non-additive gene regulation in the process of hybridization of these Spartina taxa, bringing about transgressive traits in S. densiflora x foliosa.