A comparative leaf protemics of two genotypes of Lolium prenne under drought stress

Drought stress is one of the main threats in reducing plant performance. It has been reported that endophyte infection improve drought tolerance in host grass species, but the mechanism responsible for the effect is not clear. Proteomics analysis is a beneficial tool for understanding the molecular mechanisms of drought resistance. In this study, proteomics approach was used to study the expression of drought responsible proteins in leaves of two genotypes of Lolium perenne. The experiment was set up in a completely randomized design with factorial test with two factors, the first factor was S10 (the endophyte-infected plants) and Speedy (non infected plants) genotypes and the second factor was two levels of water availability: control versus water stressed plants (about 80% moisture discharge). At first, according to TCA/acetone precipitation method total protein was extracted. The total dissolved protein was separated by SDS-PAGE electrophoresis. Identification of extracted proteins was performed by mass spectrometry technology and with proteome analysis responsive proteins was classified in different categories. It seems that fungal endophyte infected genotype with development of its root network, has more power to provide more water so perception of consequences of drought stress was delayed. Maybe symbiosis with fungal endophyte changed biochemistry and morphology of host plant and leads to increased threshold level of plant. The most induced proteins in infected genotype were in carbon and energy metabolism category. This genotype regulated different proteins of this class so kept active various processes such as photosynthesis as well as used ability of protective proteins in order to keep the activity of enzymes.