Influence of some agro-technical factors on the productivity of triple crop rotation in the agro-ecological conditions of the Upper Thracian lowland

Abstract

The amount of agricultural output per unit area depends on a large number of factors and, to a large extent, on soil fertility. The main task of agriculture is to obtain sustainable crop yields of high quality. The aim of the study is to establish the productivity of field crops (maize, barley, rapeseed), alternated in triple crop rotation under the influence of different levels of mineral fertilization and cultivation in the agro-ecological conditions of the Upper Thracian lowland. The research shows that the applied agro-technical measures influence to varying degrees the yields of the cultivated crops and total productivity of the crop rotation. The impact of the applied mineral fertilization with nitrogen and phosphorus was most significant, leading to logical increase of productivity of the cultivated crops. Non-fertilized variants show low yields at a sustainable level. Lack of fertilization influences yields significantly in rapeseed compared to maize and barley. The soil tillage system also has an impact on the level of yields obtained, better evidenced when growing oilseed rape, making the loosening an advantage over traditional plowing. Effectively increasing the productivity of triple crop rotation maize-barley-rapeseed is ensured by applying soil tillage system with loosening, optimal fertilizing rate (with alternative fertilizers) and plowing the ground vegetative mass into the soil.