Crops Productivity and Changes in Soil Nutritional Regime at Different Fertiliser Systems
T. TOMOV, I. MANOLOV, S. KOSTADINOVA and Y. MATEV
Agricultural University, BG-4000 Plovdiv, Bulgaria
TOMOV, T., I. MANOLOV, S. KOSTADINOVA and Y. MATEV, 1999. Crops productivity and changes in soil nutritional regime at different fertiliser systems. Bulg. J. Agric. Sci., 5: 419-424
The study on the influence of different fertilisation systems (1 – control, 2 – N300P300K400, 3 – N600P300K400, 4 – N900P300K400, 5 – 40 t/manure per ha + N600P300K400, 6 – N600P0K400, 7 – N600P300K0) on crop productivity, nutrient element uptake by formed biomass and changes of soil available phosphorus and potassium forms in conditions of four seasons rotation (maize – wheat – maize – barley) has been made since 1988. The experiment included two consequence rotations. The established higher productivity of crops during second rotation was due to higher maize yields. The fertilisation of crops with mineral and organic fertilisers increased productivity of rotation from 59 to 66 % in comparison with the control. The excluding of phosphorus from the fertilising combination decreased productivity of wheat from 780 to 1340 kg/ha and from 500 to 1210 kg/ha for barley, as well as content of available phosphorus in soil.
Key words: crop rotation, nutrition regime, fertilization systems