Author(s):

Harsitha Moram, Prakash NB and Eresha

Abstract: Phosphatic sludge is a byproduct from the phosphoric acid industry. Enriched phosphatic sludge (EPS) was developed as soil conditioner with substantial quantity of organic matter (~15%) by blending phosphatic sludge with press mud (containing 10 to 12 per cent phosphorus in insoluble form) and also humic acid and sea weed extracts. It also contains substantial quantities of calcium, potassium, nitrogen and micro-nutrients. The sludge was moderately alkaline in reaction (pH 8.06) with medium EC (0.97 dS m^-1). The alkaline reaction of the EPS may be due to its mixing with press mud which was generally alkaline in reaction. The EPS had high quantity of phosphorus (6.88 %) and the total N (1.51 %), K (1.20 %), Ca (1.50 %), Mg (1.10 %) and S (1.50 %) content were also in appreciable amounts in the EPS. Similarly, the total Fe, Mn, Zn and Cu contents were 4800, 1200 and 2100 and 67 mg kg^-1, respectively. Field experiment was conducted at Zonal Agricultural Research Station, V. C. Farm, Mandya, University of Agricultural Sciences (UAS), Bengaluru during 2016. Results revealed that significantly higher microbial population (bacteria, fungal and actinomycetes) were noticed in treatment T₇ receiving RDF + EPS @1000 kg ha^-1 (27.71 X10⁶, 13.59 and 13.27 X10³ cfu g^-1 soil, respectively) and lower microbial population (bacteria, fungal and actinomycetes) was recorded in control (16.99 X10⁶, 6.52 and 6.33 X10³ cfu g^-1 soil, respectively). With respect to finger millet higher microbial population was noticed in treatment T₇ which received RDF + EPS @ 1000 kg ha^-1 and lower microbial population was noticed in control. Based on results it can be concluded that addition of higher amount of organic material with low C:N to soil enhance the microbial population.

Pages: 3185-3188  |  759 Views  147 Downloads

Download (485KB)