Proto-Indo-Europeans were farmers and not pastoralists
It is interesting to note that while a couple of decades ago and perhaps more, agriculture was not considered a part of Proto-Indo-European culture, it is now no longer the case. It was mistakenly believed that the Indo-Iranians must not have practiced agriculture because apparently the Indo-Iranians did not share an agricultural vocabulary with the rest of the Indo-Europeans (i.e. the European IE). However, more recent research has clearly shown this to be an error and it is now well accepted that the Indo-Iranians shared quite a significant amount of agricultural vocabulary with the other Indo-Europeans, sufficient enough to posit agriculture at the Proto-Indo-European stage.
The overall pattern of agricultural terms has been a persistent topic in IE studies, much of which has been stimulated by the observation that while stockbreeding terms appear to be widespread across the entire range of IE stocks, agricultural terms tend to be confined more closely among the European stocks and are, from a traditional point of view at least, scarce in the Indo-Iranian languages…
…there is no case whatsoever for assuming that the ancestors of all the Indo-European stocks did not know cereal agriculture. While there may have been speculation in the past as to whether some terms might have applied originally to the gathering and processing of wild plants, terms for the plow, cultivated field, and techniques appropriate to the processing of domesticated cereals whose home range lay outside of most of Europe, suggest that all the earliest Indo-Europeans knew agriculture before their dispersals. (Encyclopedia of Indo-European Culture. Mallory & Adams, 1997).
The term that is cited as the major culprit for this error denotes a cultivated field in European languages while in Sanskrit it simply means a plain.
The second term (*haegˆros) has caused much discussion as the European cognates indicate a cultivated field (e.g. Lat ager, OE æcer [> NE acre], Grk agro´s, Arm art, all ‘field’) while the Skt a´jra- means simply ‘plain’ with no indication of agriculture. This divergence of meaning led to the proposal that the Indo-Iranians separated from the Europeans before they had gained agriculture so that we might posit a pastoral Indo-Iranian world and an agricultural European. Such a distinction is not borne out by the abundant evidence that Indo-Iranians also shared in an agricultural vocabulary… (The Oxford Introduction to Proto-Indo-European and the Proto-Indo-European World. Mallory & Adams, 2006).
…the Proto-Indo-Europeans possessed an economy based on domesticated livestock and domestic cereals. Earlier models such as those developed in detail by Wilhelm Brandenstein (1936) that suggested a marked dichotomy between arable Europeans and pastoral Indo-Iranians (or Tokharians) cannot really be sustained (Mallory 1997b) and despite a considerable number of differences there is still a substantial amount of shared agricultural vocabulary between European and Asian languages (Table 1 and 2). While the lists of cognates can certainly be criticized in certain specifics and they may well be an over-optimistic summary, I fear that there would still be a sufficient assemblage of words to indicate that both Europeans and Asiatic Indo-Europeans shared inherited words for both livestock and arable agriculture… (Twenty-first century clouds over Indo-European Homelands. Mallory 2012).