Rodgers started his first full season at 25. Manning at 22.

Manning had 138 through his first 5 seasons starting(80 games)
Rodgers had 170 through his first 5 seasons starting(78 games)

Career-wise
Manning has 2.06 TDs per start
Rodgers has 2.17 TDs per start

If Rodgers stays healthy and plays till 40, it could be close. He'll need a couple huge seasons mixed in there like Peyton had.