Just to throw in some more names, Kaf HaChayim (OC 208:10), Mishneh Halachot (6:41), Yabia Omer (OC 7:30), Sefer Eretz Yisrael (3:1) all vouch for making the change. Igrot Moshe (YD 3:129:4) rules against changing.
It's worth noting that you should really also be asking your question about the second blessing in Bentching too, which ends parallel to the question's instances with "on the land and the sustenance" and would mutatis mutandis be changed to "on the land and its sustenance." In fact, most of the above cited opinions do not distinguish between the cases, with some exceptions such as Yabia Omer who notes that there existed an active custom to change "Al haMichya" but no active custom to change "Al haMazon" and rules accordingly.
An additional note: the Yerushalmi (Brachot 6:1) brings a different version of the before and after bracha for a certain sweet rice dish (what we have as SheHaKol (probably) and Borei Nefashot). The before and after brachot, respectively, per this other opinion are:
בורא מיני מעדנים...
...who created types of delicacies.
אשר ברא מיני מעדנים לעדן בהן נפש כל חי בא"י על הארץ ועל מעדניה...
...that he created types of delicacies to delight with them all living souls. Blessed are you Hashem on the land and on its delicacies.
We see that there exists another bracha (and a semi-grain related one!) where this change is made. (I'm assuming it's a change because the Yerushalmi is in Israel. I assume if that rabbi had traveled to Babylon he would have said ועל המעדנים.)
This seems to reject the authorities who justify limiting the switching to fruit blessings by describing the special connection that fruit of the seven species has with the land. It doesn't prove that the switch should be made by grain (which does seems to parallel rice), but it rejects a main logic against making that switch.