INFLUENCE OF "ORGANIC MAX" ORGANIC FERTILIZER ON FERTILITY INDICATORS OF CLOSED SOIL AND YIELD OF TOMATOES

Abstract

The results of studies of changes in fertility indicators of closed soil (in two film greenhouses) when introducing a new organic fertilizer ("Organic MAX") based on lignite (brown coal) and animal waste (chicken droppings with humidity up to 60%) are presented. Three types of fertilizer were applied, namely, crushed lignite (to a fraction of 0–5 mm), "Organic MAX-20" (lignite of 20% chicken droppings) in the first greenhouse and "Organic MAX-30" (lignite of 30% chicken droppings) in the second greenhouse in 2022. When five tons of fertilizers were applied per hectare, an increase in humus content by 0.31% and 0.38% was detected with an increase in part of the chicken droppings in the first greenhouse from 1.93% to 2.41% in the second. Accordingly, an increase in the content of readily hydrolyzed nitrogen by 28–67.2 mg/kg and mobile potassium compounds by 12.9–56 mg/kg was observed. The largest application of fertilizers contributed to the accumulation of mobile phosphorus compounds, their content increased by 20.6–81.7 mg/kg of soil. There was an increase in the sum of absorbed bases and a decrease in the acidity of the soil solution. In 2023, an additional five tons of Organic MAX-30 were added in two greenhouses, which contributed to an increase in all indicators, especially mobile phosphorus compounds (moved to the very high support group). As a result of two years of applying organic fertilizer to closed soil, humus moved from the low provision group to the medium provision group; phosphorus from the group of very low and low support – to the group of very high; potassium from the group of medium and high – to the group of high and very high provision; nitrogen increased significantly, as well as the sum of the absorbed bases. The effect of the new fertilizer "Organic MAX–20" on the yield of two tomato hybrids: Suomi (plums) and Casta (salad) was also investigated. The application of this fertilizer provided an increase in the yield of the Suomi variety 576 kg (65%) and the Kasta hybrid 476 kg (39%). All the above data demonstrate the high efficiency of this organic fertilizer.