Chemical analyses of substrates (solution from the root environment) using the following methods: N-NH4 and N-NO3 by distillation according to Bremner in Starck`s modification, P – colorimetrically with ammonium vanadomolybdate (Thermo, Evolution 300), K, Ca, Mg by AAS (Perkin-Elmer, Analyst 300), EC – conductometrically, pH – potentiometrically