Thiobacillus Oxidants and Their Role in Sulphur Fixing in Soil

Abstract

Sulphur is considered the fourth major plant nutrient after nitrogen, phosphorus and potassium. These four elements are essential for the growth and development of plants, especially in the agriculture crop production. The importance of sulphur is equal to that of nitrogen in terms of protein synthesis and in terms of crop uptake it exceeds even that of phosphorus. The majority of sulphur taken up by plant root is in the form of sulphate which undergoes a series of transformation prior to its incorporation into the original compound. By composting sulfur, rock phosphate and soil it was found that sulfur is rapidly oxidized to sulfuric acid. The acid acts upon the tricalcium phosphate, converting in to the di and mono calcium salts. Isolation of sulfur oxidizer requires sample mainly is the canal water, sludge sample, industrial waste sludge and sewage sludge. By composting sulfur, rock phosphate and soil it was found that sulfur is rapidly oxidized to sulfuric acid. On inoculating such compost into proper culture media get the success in isolating small bacteria which is sulfur oxidizer. Sulfur oxidizing bacteria have the different type which is different in the morphology, characteristics and growing condition. For the growth of the sulfur oxidizing bacteria different medium are available. For that screening and isolation of the sulfur oxidizing bacteria four different samples taken namely API sludge, surge pond, and soil near by compost tree. 4 gm sample added in growth medium and pH reduction is measured and pH below 3.5 gives next transformation. Quantify by the calculating the sulphate concentration. Different biochemical test are used for the genus identification of all isolates. Biochemical tests include methyl red test, indole test, starch hydrolysis test, urease hydrolysis test, and gelatin liquififaction test. For genus level identification check fermentative sugar utilize or not by the isolates. Fermentative sugar includes glucose, fructose, galactose, lactose, sorbitol, adonitol, and rhamnose. Isolated species belongs to pseudomonas, vibrio, flavobacterium, and aeromonas. By best combination of sulfur oxidizing bacteria species and sulfur we enhance the bioavailability phosphate in soil.