Planetary mass against metallicty a) for all the planets in the system and b) for the most massive planets in each planetary systems. All the planets are detected with the radial velocity technique and planet hosts are FGK dwarf stars. The small circles correspond to individual planets and the large circles represent the average metallicty for the four mass bins M_P < 0.1  M_Jup; 0.1  M_Jup ≤ M_P < 1  M_Jup; 1  M_Jup ≤ M_P < 4  M_Jup; and M_P > 4  M_Jup. The error bars indicate the standard deviation of the [Fe/H] in each bin.