Page 412 - Demo

416 PROCEEDINGS OF INTERNATIONAL SCIENTIFIC CONFERENCE ON APPLIED BIOTECHNOLOGYThe microbiological preparation produced by the Institute of Soil and Agricultural Chemistry. It contains the following microbial composition: Nitrogen-fixing microorganisms: %u2265 1.5x108 CFU/g, Phosphate-solubilizing microorganisms: %u2265 1.5x108CFU/g, Potassium-solubilizing microorganisms: %u2265 1.5x108 CFU/g. This product is a result of the research topic %u201cResearch and development of biological solutions to improve barren land%u201d and has been developed and applied in the improvement of coastal sand through the project %u201cImproving the production process of microbial preparations for use in improving coastal sand.%u201d [8]Phu N%u00f4ng brand seeds for mustard greens, water spinach, and tomato plants.2.2. Methods2.2.1. Soil sampling method: According to TCVN 4046:1985 [9] for cultivated land.2.2.2. Methods for analyzing soil physical and chemical indicatorsParticle size analysis: Soil is treated with 30-35% hydrogen peroxide (H2O2) to remove organic matter. Separate the particle size fractions of the soil sample using a mixture of sodium hexametaphosphate (NaPO3)6 and sodium carbonate Na2CO3. Determine the silt and clay content using a pipette, determine the sand content using sieves (TCVN 8567:2010) [10]; Organic matter content: National standard TCVN 9294: 2012[11] - Fertilizers - Determination of total organic carbon by the Walkley-Black method; To determine total nitrogen, the Kjeldahl method is used. This method relies on converting all nitrogen in organic compounds into ammonium salts through digestion with sulfuric acid (H2SO4) catalyzed by potassium sulfate (K2SO4) and selenium (Se) (TCVN 6498 %u2013 1999)[12]; Available phosphorus: dissolve the forms of phosphorus compounds in the soil with a