"натура" literally means something natural. Here the word is used as a synonym for "български храни". And so the last sentence means that there are no raw material to be exported.

I'd agree with Gratsiela, but only in the point that this seems to be the idea of the author. Although I don't agree completely that "натура" means something natural. Neither I've ever heard "натура" to be used in that sense, nor there is such meaning listed in any dictionary and in that text none of the listed meanings makes much sense at all. Maybe, (if the quote is truncated), it could be some kind of a pun ( i.е. with "в натура"?), but I doubt it's actually a real quote. I'd say - DW needs to pay more attention to the Bulgarian articles - in recent years their quality dropped notably.

Имайки предвид годината в която се е състоял разговора, смятам че думата е използвана като термин. Например, ако имаме 100% производство на ябълки, 60% са отивали на пазара и са се продавали, като стока срещу пари. Останалите 40% са се разменяли в натура, стока срещу стока. Ако вече си разменил своите 40% ти вече нямаш какво да разменяш, или иначе казано, нямаш вече натура.