  Using near-infrared speckle interferometry we have obtained resolved
JHK-photometry for the components of 58 young binary systems. From these
measurements, combined with other data taken from literature, we derive masses
and particularly mass ratios of the components. We use the J-magnitude as an
indicator for the stellar luminosity and assign the optical spectral type of
the system to the primary. On the assumption that the components within a
binary are coeval we can then place also the secondaries into the HRD and
derive masses and mass ratios for both components by comparison with different
sets of current theoretical pre-main sequence evolutionary tracks. The
resulting distribution of mass ratios is comparatively flat for M(2)/M(1) >
0.2, but depends on assumed evolutionary tracks. The mass ratio is neither
correlated with the primary's mass or the components' separation. These
findings are in line with the assumption that for most multiple systems in T
associations the components' masses are principally determined by fragmentation
during formation and not by the following accretion processes. Only very few
unusually red objects were newly found among the detected companions. This
finding shows that the observed overabundance of binaries in the Taurus-Auriga
association compared to nearby main sequence stars should be real and not the
outcome of observational biases related to infrared observing.
