Use Of Phosphorus Fertilizers On Irrigated Light Chestnut Soil In The South-East Of Kazakhstan

Abstract

The article presents the results of long-term studies carried out in long-term experiments on the study of the fertilization system of sugar
beet in the beet crop rotation and with its permanent cultivation on irrigated light chestnut soil. It is shown that with long-term (57-58
years) and systematic use of phosphorus fertilizers against the background of nitrogen-potassium (NK) fertilizers in the soil, background
with different levels of phosphorus supply in the arable and subsoil layers are created. Single, one-and-a-half, double norms of phosphorus
fertilizers, systematically applied in crop rotation and with permanent cultivation of sugar beets, not only increase the content of mobile
phosphorus in the arable layer, respectively, to 49.0; 51.9; 59.0 mg/kg of soil, but also the content of the sum of loosely bound and
different basic phosphates (CaPI + CaPII), the nearest reserves of phosphorus available to plants in crop rotation and in monoculture
conditions. Changes in the nutrient regime of the soil affect the chemical composition of cultivated crops, in particular, sugar beet, and the
dynamics of biomass accumulation. Accordingly, the yield of sugar beet increases to 53.3-57.7 t/ha in crop rotation and up to 50.3-56.1
t/ha in monoculture with a simultaneous increase in sugar content up to 16.0-16.7% and total sugar harvest with 1 ha of crops.