Is this what you want?

use strict;
use warnings;

# if the perl script takes input and output strings as arguments
my $perl_script = "perl script_to_execute input output";

# print to see what is being executed
print "$perl_script\n"

my $script_exe = `$perl_script`;

# To check for errors
print "$script_exe\n";
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OR directly :

my $script_exe = `perl perl_script_to_run input output`;
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NOTE: untested
UPDATE As Ratazong suggests, you can also try:

my $cmd = "perl script_to_execute input output";

print STDERR "$cmd\n";
system($cmd);
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