Study of the application of phosphorus-solubilizing fertilizer on chernozems of the forest-steppe zone of the North Kazakhstan Region

Abstract

Background and Aim. The soils of the North Kazakhstan region are mainly represented by ordinary and southern chernozems of the forest steppe and steppe zones. The intensive use of arable land has led to a marked decline in soil fertility, and consequently, to unstable grain yields. Therefore, it is essential to evaluate the effectiveness of Pseudomonas spp.-based biofertilizers for targeted soil fertility management. This study examined the effect of the bacterial phosphorussolubilizing fertilizer Biophos on soil phosphorus content.

Materials and Methods. Agrochemical studies were conducted in 2024 at the Eshmanov Farm (Kyzylzhar District, North Kazakhstan Region). The study relied on the results of a continuous agrochemical survey of arable soils. Parameters measured included soil pH (water extract), mobile phosphorus and potassium (Machigin method), and nitrate nitrogen in the topsoil. The measurements were taken every 30 days

Results. At the beginning of the experiment, nitrate nitrogen content in the arable horizon was - 9,09 mg/kg. After harvest its content in the variant with combined application of ammophos and Biophos was 4,8 mg/kg, compared with 2,73 mg/kg in the control. The content of mobile phosphorus increased during the growing season from an average level 25,0 mg/kg to a high level of 87,33 mg/kg. After harvest, phosphorus reserves remained elevated (45,69 mg/kg), despite crop removal. Compared with the control, mobile phosphorus content was higher by 20-25 mg/kg. Soil pH remained stable at an optimal level (7,2 before the experiment) ensuring nutrient availability and supporting plant growth.

Conclusion. The use of the phosphorus-solubilizing fertilizer "Biophos" in combination with ammophos in the forest-steppe zone of northern Kazakhstan is guaranteed to increase crop yields. The controlled and justified use of the phosphorus-solubilizing fertilizer "Biophos" in combination with ammophos in the forest-steppe zone of northern Kazakhstan is guaranteed to increase the level of nutrients in the soil and maintain the soil environment at a neutral level. This is beneficial for the activity of soil microorganisms and soil formation processes.