Membrane Lipid Composition and Drought Tolerance In Bermudagrass.

Drought stress is a major limiting factor for warm-season turfgrasses to grow during summer in the U.S. transition zone. Genotypic variation in drought resistance exists among bermudagrasses [Cynodon dactylon (L.) Pers.], but the mechanisms of drought resistance are poorly understood. Our objectives were to quantitatively profile membrane lipid molecule species in three warm-season grasses under drought stress, discover relationships between specific lipid compositions and drought tolerance, and identify specific membrane lipid molecules as potential biomarkers for drought tolerance in bermudagrass. Grasses included a high drought resistance cultivar ‘Celebration', low drought resistance cultivar ‘Premier’, and a new released cultivar ‘Latitude 36’. The experiment was a completely randomized experimental design with two factors (three genotypes and two drought treatments) and five replications. To maintain well-watered conditions, 100% of water lost via evapotranspiration (ET) during the previous 3 d was replaced; Drought treatment was withholding irrigation until complete leaf wilting of most plants. The leaf samples were taken 2 times which include before treatment and dry treatment for 8 days. Total 60 dry lipid samples were analyzed by an automated electrospray ionization tandem mass spectrometry (ESI-MS/MS) approach.