BIOLOGICAL PREPARATION EFFECTS ON THE PHYSIOLOGICAL GROWTH OF PINUS SYLVESTRIS L. SEEDLINGS AT THE CHERNOZEM SOIL IN NORTHERN KAZAKHSTAN.

Pinus sylvestris L. is a widely used tree in landscaping, and therefore, its high-quality planting material is most relevant in Kazakhstan. The recent study evaluated the effects of the various biological preparations on the physiological growth of the P. sylvestris L. seedlings in the ordinary chernozem of Northern Kazakhstan. The study used several methods for evaluation, i.e., sowing and planting, measurements, data compilation, formulation, and analysis, and recommended computer software. In 2022, sowing 20 kg seeds of P. sylvestris ensued on a 0.4 ha area. For the agrochemical assessment of the experimental site, soil samples collected underwent a chemical composition analysis. The morphological parameters of the upper and lower parts of the seedlings also reached identification. Concerning the indicators of agrochemical assessment of the soil after using biological preparations, i.e., Agrarka (1.5%) and Agro-MIX (10%), the sum of macronutrients and exchangeable calcium and magnesium was high. The results also showed that the average number of seedlings incurred enhancements using the Agro-MIX (10%). Therefore, Agrarka and Agro-MIX can be helpful in forest nurseries as effective growth stimulators in growing planting material for tree and shrub species. [ABSTRACT FROM AUTHOR]