LITHIUM AND BERYLLIUM IN MAIN-SEQUENCE STARS

Li and Be abundances in Main Sequence stars later than F0 are reviewed. Observations of Li in open cluster stars and metal-poor dwarf halo stars has promoted the development of a great variety of models invoking transport processes in the outermost layers of these stars. Although measurements in their present state do not allow to establish definitive conclusions on which process is the most important for each range of masses, they do manifest that metallicity and stellar rotation play an important role in controlling the processes which trigger disappearance of these elements from stellar atmospheres.