Source: TW
rAmAyaNa
What was the scriptural basis for the fertilizing putrakAmeShTi that R^ishyasR^iNga performed for dasharatha? In the rAmAyaNa, R^ishyashR^iNga himself informs us thus:
iShTiM te .ahaM kariShyAmi
putrIyAM putra-kAraNAt |
atharvashirasi proktair
mantraiH siddhAM vidhAnataH ||
To procure sons for you, I must perform the son- generating ritual. It must be done as per the [ritual] injunctions and rendered efficacious by mantra-s of the atharvashiras.
mahAbhArata
Now what is this atharvashiras? The same word is also mentioned 7 times (across all recensions) in the mahAbhArata. We hold that it should not be conflated with the shaiva upaniShad going by that name.
The mahAbharata gives us a further clue:
“atharvashirasA chaiva nityam AtharvaNA dvijAH |”
This suggests that it was indeed an atharvan text.
Conclusion
Hence, we posit that it was an ancient atharvan collection either preceding that extant atharvan shAkhA-s or a collation of atharvan material drawn from the proto-AV that was used in various rituals. Thus, one may say that despite is ashvamedha-like features, the core of the putrakAmeShTi was performed using atharvan mantra-s.
Specifically, we propose that AV-vulgate 5.25 and AV-paippalAda 3.39 (known as the putrakAma sUktra) were used in the rite and was part of this atharvashiras.