ДИНАМИКА ПОДВИЖНЫХ ФОРМ АЗОТА И ФОСФОРА В СЕРО-БУРЫХ ПОЧВАХ ПОД ТОМАТОМ ПРИ ВНЕСЕНИИ УДОБРЕНИЙ

Abstract

This article examines the effect of mineral and phosphorus fertilizers on the dynamics of available nitrogen and phosphorus content in graybrown stony soils of the Republic of Tajikistan during tomato cultivation. The aim of the study was to assess changes in soil nutrient status during various stages of tomato development (budding, flowering, fruiting, and ripening) with the application of varying rates of nitrogen-potassium fertilizers in combination with superphosphate and rock phosphate.

The field experiment included six treatments: a control without fertilizer, a background N150K50 fertilizer, and a background fertilizer in combination with superphosphate (P100) and rock phosphate at doses of P100, P200, and P300. It was found that the application of superphosphate and rock phosphate (especially at a dose of P300) significantly increased the content of ammonium and nitrate nitrogen, as well as available phosphorus, in the arable soil layer (0–30 cm) compared to the control.

Maximum values were observed during the budding phase, with subsequent declines as the plant matures. Despite the overall increase in soil nutrient availability, nitrogen availability in gray-brown stony soils remains relatively low. This indicates the need for further optimization of rates and combinations of mineral and phosphorus fertilizers in tomato cultivation.