During the period 2011 – 2013 a field experiment was conducted at the experimental field of IASS “Obraztsov chiflik” – Ruse, with ecologically grounded crop rotation, including the cultivation of two legumes /field beans, peas/ and two cereals /wheat, malting barley/ on an area after conversion. The experiment started after the eightfold scheme of Georges Ville in 3 replications, situated after Ryumker, the size of the harvesting plot being 52,5m2. Pesticides were not applied on the crops, also and synthetic fertilizers and improversof soil, prohibited for the organic production.
The objective of the study was to observe and describe the biological regulation of weeds in legumes and cereals, grown under conditions of organic farming.
In the organic field, the diversity of weed species was influenced by climatic conditions, soil tillage and crops. There were differences in weed infestation of crops only in terms of quantity of weeds per m2. In that case the differences in weed infestation were in direct relationship with certain biological characteristics of the crops. The species Matricaria chamomilla (L.), Anthemis arvensis (L), Capsella bursa-pastoris (L.), Setaria viridis (L.), Echinochloa crusgalli (L.), Digitaria sanguinale (L.), Lamium purpureum (L.), Convolvulus arvensis (L.) и Cirsium arvense(L.) were reported over the whole three-year period.