  We theoretically study the loading of a two-species Bose-Einstein condensate
to an optical lattice in a tightly-confined one-dimensional trap. Due to
quantum fluctuations the relative inter and intra species phase coherence
between the atoms and the on-site atom number fluctuations are reduced in the
miscible regime. For the immiscible case the fluctuations are enhanced and the
atoms form metastable interleaved spatially separated domains where the domain
length and its fluctuations are affected by quantum fluctuations.
