Grains

In the R^igveda there are, at best 3 ambiguous references to rice. The word is odana – while today it is taken to mean rice, it could simply be a porridge which could have been made from another grain. The primary grain in the RV is yava – barley & there’s no millet.

By the late YV period rice becomes dominant. In the archaeological record, we see that rice rose to dominance along with lentils in the post-urban Harappan lands where the Arya-s had settled. Thus, the rise of rice is keeping with the Aryan settlement in India. In the same time millets also started rising in cultivation, though not to the level of rice. Thus, we see occasional mentions of millets in through the late YV traditions.

It is only in the latest Vedic age & beyond that the millets become more prominent which might mark the movement deeper into the peninsula where a greater diversity & quantity of millets were likely cultivated – like bAjra in hiraNyakeshin’s sUtra-s

To add to the above, at least in the Āgrahāyaṇi, the Śyāmaka millet is offered in agni & Baudhāyana-Śrautasūtra 28.13 provides for Priyaṅgu & Śyāmaka millets as substitutes for Vrīhi & Yava in case of unavailability. -GA