Reverse dependency generation with zypper

Zypper 1.14.33+ has --requires-pkg which might yield more results than --requires. See here for details.

# zypper se --requires-pkg packagename

# zypper help search | grep -A1 requires-pkg
--requires-pkg          Search for all packages that require any of the provides of the
                        package(s) matched by the input parameters.

You can search (abbreviated with "se") for packages that require a certain package with:

zypper se --requires packagename

Also, you can search only among installed packages with:

zypper se -i --requires packagename

For example, to look for packages requiring libpng:

# zypper se -i --requires libpng
Loading repository data... 
Reading installed packages...
S | Name                        | Summary                                                             | Type   
--+-----------------------------+---------------------------------------------------------------------+--------
i | DirectFB                    | Graphics Library for Framebuffer Devices                            | package
i | MPlayer                     | Multimedia Player                                                   | package
i | cairo-devel                 | Development environment for cairo                                   | package
etc.