  The major interactions are known to trigger star formation in galaxies and
alter their colour. We study the major interactions in filaments and sheets
using the SDSS data to understand the influence of large-scale environments on
the galaxy interactions. We identify the galaxies in filaments and sheets using
the local dimension and also find the major pairs residing in these
environments. The star formation rate and colour of the interacting galaxies as
a function of pair separation are separately analyzed in filaments and sheets.
The analysis is repeated for three volume limited samples covering different
magnitude ranges. The major pairs residing in the filaments show a
significantly higher star formation rate (SFR) and bluer colour than those
residing in the sheets up to the projected pair separation of $\sim 50$ kpc. We
observe a complete reversal of this behaviour for both the SFR and colour of
the galaxy pairs having a projected separation larger than 50 kpc. Some earlier
studies report that the galaxy pairs align with the filament axis. Such
alignment inside filaments indicates anisotropic accretion that may cause these
differences. We do not observe these trends in the brighter galaxy samples. The
pairs in filaments and sheets from the brighter galaxy samples trace relatively
denser regions in these environments. The absence of these trends in the
brighter samples may be explained by the dominant effect of the local density
over the effects of the large-scale environment.
