Rationale for the Soil Water Regime and Drip Irrigation Regulations for Sweet Cherry Seedlings

Abstract

This paper discusses the effect of drip irrigation on the yield and quality of sweet cherry yearlings. The experiment involved three variants. In the control variant, the soil moisture content in the 0.4-m layer was maintained at a level not less than 80% of the field moisture capacity (FMC) throughout the entire growing season. In the second variant, the soil moisture was maintained at 80% of the FMC in the 0.2-m layer until the beginning of the active bole growth phase with subsequent extension of the wetted layer to 0.4 m. In the third variant, the water regime differentiated by layers (similar to the one in the second variant) was maintained until the end of the active seedling growth phase; then the preirrigation moisture level was reduced to 70% of the FMC. Watering rates required to maintain the soil moisture level at 80% of the FMC were 50 m³/ha for the 0.2-m layer and 100 m³/ha for the 0.4-m layer. A watering rate of 160 m³/ha was required to maintain the soil moisture level at 70% of the FMC in the 0.4-m layer. The seasonal irrigation requirements were 1675, 1763, and 1577 m³/ha, respectively. The best values of such parameters as central bole height, root collar diameter, and share of class one seedlings were registered in the second variant; they exceeded the control values by 50 mm, 4.3 mm, and 6%, respectively. The third variant was the most water-saving option: the irrigation water costs were lower by 110 m³/ha in comparison with the control and by 186 m³/ha in comparison with the second variant.