Programs can only receive strings as arguments.
"\@blastLine" will pass the name of the variable (Completly useless).
"@blastLine" will stringify the contents of @blastLine. "@blastLine" is identical to join($", @blastLine).

What are you trying to do anyway???

By the way, if the script you are executing is a CGI script, command line parameters have a special meaning for it. If it's not, you shouldn't end its name with .cgi.