Not very likely, although he does have a shot at second place.

After four games, Julio is averaging 85.5 yards/game.  If he continues at that current place, that will give him 1368 yards, assuming  he plays all 16 games.

Back in 1960, Bill Groman set an NFL record 1473 yards (in 14 games),  a record that still stands today.

Anquan Boldin had the second best year for a rookie WR (in terms of yardage) with 1377 in 2003. 

In addition to being second place in yardage, Boldin is also the record holder for receptions by a rookie, with 101.  

Julio has 24 catches after 4 games, which could give him 96 by the end of the year, 6 more than the 2nd place Terry Glenn (1996).

Keep up the good work!