Influence of biological preparations on soil nitrogen and phosphorus content in the spring wheat crop

Intensifying production of agriculture, rising prices of energy resources and the EU ecological policy goals are forcing farmers to seek solutions to reduce industrial and production costs and energy resources. At the same time, new and efficient measures are sought to increase soil fertility and quality. The experiment was conducted in 2015-2017 in the Experimental Station of Aleksandras Stulginskis University, in Calc(ar)i-Endohypogleyic Luvisol, a semi-neutral (pHkci 6.8), highly phosphorous (226.6 mg kg"1 P2O5), mid-potassium-level (105.0 mg kg"1 K2O), mid-humus-level (2.33%) soil, in order to evaluate the effect of biological preparations BactoMix2, BactoMix5 and Rhizobacterin on nitrogen and phosphorus content in the soil. The experiment was carried out in three repetitions in a spring wheat crop. Experiment variants: 1) biological preparations were not used, 2) biological preparation BactoMix2 (Enterobacter V-402 D and 409 D), norm 1.0 1 ha"1, 3) biological preparation Rhizobacterin (associative nitrogen-fixing bacteria Klebsiella planticola 5), norm 2.0 1 ha"1, 4) biological preparation BactoMix5 (Bacillus subtilis V-845 D and V-843 D, Pseudomonas aurantiaca, Bacillus megatarium and Brevibacillus sp.), norm 1.0 1 ha"1. Variants were arranged randomly. The size of the initial field was 240 m2, the size of accounting field was 128 m2. At the beginning of the experiment in 2015 nitrogen content in the soil variated from 0.132 to 0.136%. After harvest of the spring wheat higher soil nitrogen content was detected in the fields sprayed with biological preparations. In the fields sprayed with Rhizobacterin nitrogen content in the soil increased significantly - 31.6%. The similar trend is established in 2016 and 2017. Phosphorus content at the beginning of the experiment in the soil variated from 230.3 to 242.7 mg kg"1. [...]Vytauto Didžiojo universitetasŽemės ūkio akademij