Parameters of optimization of alfalfa nutrition with zinc at different availability of this element in sod­podzolic sandy loam soil

Abstract

In a field experiment on sod-podzolic sandy loam soil, it was established that when the gross zinc content increases from low (23,3 mg/kg) to excessive level (35,7 mg/kg), the amount of mobile zinc increases from 2,6 to 11,1 mg/kg. The share of mobile zinc accounts for from 11,1 to 31,1 % of its total content. Zinc uptake by alfalfa plants increases linearly with increasing zinc concentration in the soil. An increase in the content of mobile zinc in the soil from low to excessive levels increases the accumulation of the element in alfalfa plants from 19,7 to 30,3 mg/kg dry weight.

In the technology of alfalfa cultivation on sod-podzolic sandy loam soil, low- and medium-provided zinc, foliar feeding in the branching phase with zinc fertilizer in doses of 0,15 and 0,10 kg/ha a. i. increases the yield of dry mass by 17,4 and 7,9 c/ha and increases the zinc content in plants to 25,6 and 24,0 mg/kg with a profitability of 87,2 and 25,5 %, respectively.