Mode Of Action:
Due to immobilization of phosphate by mineral ions such as Fe, Al and Ca and organic acids, the rate of available phosphate in soil is well below plant needs. Chemical fertilizers are also immobilized in the soil, immediately so that only 20% of added fertilizer is absorbed by plants. PSB converts insoluble phosphatic compounds such as rock phosphate, bone meal and basic slag, particularly the chemically fixed soil phosphorus into available form. Such organisms not only assimilates phosphorus but also cause a large amount of soluble phosphate to be released in excess of their own requirements and saves P2O5 up to 30 – 50 Kg/ ha. Phosphorus solubilizing activity is determined by the ability of microbes to release metabolites such as organic acid (lactic acid, malic acid, gluconic acid, fumaric acid, succinic and acetic acid). Inorganic phosphorus is solubilized by action of organic (gluconic, ketogluconic) and inorganic acids (HCl) secreted by PSB and maintain the soil pH. The pH of rhizosphere is lowered by the bio-carbonates release (anions/cation balance) and oxygen/carbon oxide gaseous exchange. Phosphorus solubilizing ability of PSB has direct correlation with pH of the medium.
Benefits To The Crop:
Increases micronutrients availability to plant from the soil like Mn, Mg, Fe, Mo, B, Zn and Cu in addition to P2O5.
Encourages faster root growth for water and nutrient uptake.
PSB produces organic acids like malic, succinic, fumaric, citric, tartaric acid and acetic acid which fasten the P2O5 uptake, maturity and increase yield.
Increases resistance towards diseases and drought tolerance due to rapid cell development in the plants.
Compatible to other beneficial microbes with the plant like growth promoting substance.
Reduces 25 – 30% phosphatic fertilizer requirement.
Cereals (Wheat, Paddy, Maize, Barley), Pulses (Soybean, Green gram, Chickpea, Black gram, Pigeon Pea, Pea), Oil seeds (Sunflower, Ground Nut, Mustard, Coconut, Safflower), Fibrous (Cotton, Jute), Vegetables, Fruit and Plantation crops