The impact of apple orchard fertigation on the seasonal dynamics of the soil nutrients

T.G. Fomenko, V.P. Popova, A.I. Kuzin
The fertigation of fruit trees significantly affects soil nutrient supply. The purpose of this research was to evaluate the seasonal dynamics of N, P, and K distribution in the soil of an apple orchard under fertigation. The study was conducted using three apple cultivars; ‘Golden Rangers’, ‘Renet Simirenko’, ‘Gala’ grafted on to М9-T337. According to the WRB system (2014), the trial field soil falls into Vorony-Calcic Chernozems. The fertigation was conducted every 3-4 days from fruit-set to commercial maturity of fruits. In the periods with enough precipitation, we postponed drip irrigation to a later date. Soil samples were regularly collected from apple orchards of various ages (2015-2019). Soil was taken from directly under the drip emitters, 20 and 40 cm away from the drip point and in the center of inter-row space. The ammonium-N concentrations in the wetted soil volume strongly varied when the orchard was fertigated, probably because of its rapid oxidation to nitrates. Soil N-NO3 concentration increased when fertigation was applied, despite partial leaching of unassimilated nitrogen in the winter and spring period. The highest concentration of nitrate-N was observed 20 cm away from the drip emitters. On the contrary, P and K concentrations were the highest directly under the drip emitters. There was a strong correlation between phosphorus content (r=0.95) and potassium (r=0.81) in the soil directly under the drip emitters and the duration of fertigation. These results will improve the evaluating methods of soil nutrient supply to develop optimal fertigation programs.
Fomenko, T.G., Popova, V.P. and Kuzin, A.I. (2022). The impact of apple orchard fertigation on the seasonal dynamics of the soil nutrients. Acta Hortic. 1333, 247-254
DOI: 10.17660/ActaHortic.2022.1333.32
apple orchards, mineral fertilizers, nutrient distribution, soil agrochemical properties, сhernozem soils, soil sampling method

Acta Horticulturae