  From the VIMOS VLT Deep Survey we use a sample of 6447 galaxies with I_{AB} <
24 to identify 251 pairs of galaxies, each member with a secure spectroscopic
redshift, which are close in both projected separation and in velocity. We find
that at z ~ 0.9, 10.9 +/- 3.2 % of galaxies with M_B(z) < -18-Qz are in pairs
with separations dr < 20 kpc/h, dv < 500 km/s, and with dM_B < 1.5,
significantly larger than 3.76 +/- 1.71 % at z ~ 0.5; we find that the pair
fraction evolves as (1+z)^m with m = 2.49 +/- 0.56. For brighter galaxies with
M_B(z=0) < -18.77, the pair fraction is higher and its evolution with redshift
is somewhat flatter with m=1.88 \pm 0.40, a property also observed for galaxies
with increasing stellar masses. Early type, dry mergers, pairs increase their
relative fraction from 3 % at z ~ 0.9 to 12 % at z ~ 0.5. We find that the
merger rate evolves as N_{mg}=(9.05 +/- 3.76) * 10^{-4}) * (1+z)^{2.43 +/-
0.76}. We find that the merger rate of galaxies with M_B(z) < -18-Qz has
significantly evolved since z ~ 1. The merger rate is increasing more rapidly
with redshift for galaxies with decreasing luminosities, indicating that the
flat evolution found for bright samples is not universal. The merger rate is
also strongly dependent on the spectral type of galaxies involved, late type
mergers being more frequent in the past, while early type mergers are more
frequent today, contributing to the rise in the local density of early type
galaxies. About 20 % of the stellar mass in present day galaxies with
log(M/M_{sun}) > 9.5 has been accreted through major merging events since z ~
1, indicating that major mergers have contributed significantly to the growth
in stellar mass density of bright galaxies over the last half of the life of
the Universe.
