SALT STRESS RESPONSES IN PINUS HALEPENSIS

Metapontum Forest Reserve is an artificial formation located between mouths of Bradano and Basento river, it is composed prevalently of Aleppo pine (Pinus halepensis). In recent years, the Metapontum coast is characterized by a strong erosive process which has really removed the dune behind the beach moving in the inland and causing the decline of the historical pinewood. This negative effect on plant was induced by an increase in soil salinity, which is one of the major abiotic stresses. A clear understanding of the molecular mechanisms involved in plants response to salt stress is fundamentally important for plant biology. The salinity soil causes broad variety of physiological and biochemical processes, as oxidative damage, also has a negative effect on energy metabolism, which unavoidably resulted in a decreased ATP production through photophosphorylation and, thus, affected the Calvin cycle in photosynthesis. A proteomic approach was utilized to identify key protein which result to be directly responseve to salt stress. Total proteins were extracted from the leaves by a combination of TCA-acetone and phenol, and separated by two-dimensional gel electrophoresis at pH 5-8. Spots were stained with Comassie Brilliant Blue and analyzed with the software PDQuest 8.0 (Bio-Rad) to identify differentially expressed polypeptides. Preliminary analysis revealed around 29 differentially expressed proteins, and they were sequenced by MALDI TOF and LC-MS/MS. Sequenced spots were classified in different functional classes.