Rock inhabiting potassium solubilizing bacteria from Kerala, India: characterization and possibility in chemical K fertilizer substitution.
The role of rock inhabiting bacteria in potassium (K) solubilization from feldspar and their application in crop nutrition through substitution of fertilizer K was explored through the isolation of 36 different bacteria from rocks of a major hill station at Ponmudi in Thiruvananthapuram, Kerala, India. A comprehensive characterization of K solubilization from feldspar was achieved with these isolates which indicated that the K solubilizing efficiency increases with decrease in pH and increase in viscosity and viable cell count. Based on the level of K solubilization, two potent isolates were selected and identified as Bacillus subtilis ANctcri3 and Bacillus megaterium ANctcri7. Exopolysaccharide production, scanning electron microscopic and fourier transform infrared spectroscopic studies with these efficient strains conclusively depicted the role of low pH, increase in viscosity, and bacterial attachment in K solubilization. They were also found to be efficient in phosphorus (P) solubilization, indole acetic acid production as well as tolerant to wide range of physiological conditions. Moreover, the applicability of K containing rock powder as a carrier for K solubilizing bacteria was demonstrated. A field level evaluation on the yield of a high K demanding tuberous vegetable crop, elephant foot yam (Amorphophallus paeoniifolius (dennst.) nicolson) established the possibility of substituting chemical K fertilizer with these biofertilizer candidates successfully.
Division of Crop Protection, ICAR-Central Tuber Crops Research Institute (CTCRI), Sreekariyam, Trivandrum, Kerala, India.
Indira Parameswaran
IP
Anjanadevi
Division of Crop Protection, ICAR-Central Tuber Crops Research Institute (CTCRI), Sreekariyam, Trivandrum, Kerala, India.
Neetha Soma
NS
John
Division of Crop Protection, ICAR-Central Tuber Crops Research Institute (CTCRI), Sreekariyam, Trivandrum, Kerala, India.
Kuzhivilayil Susan
KS
John
Division of Crop Protection, ICAR-Central Tuber Crops Research Institute (CTCRI), Sreekariyam, Trivandrum, Kerala, India.
Muthulekshmi Lajapathy
ML
Jeeva
Regional Centre, ICAR-CTCRI, Bhubaneswar, India.
Raj Shekhar
RS
Misra
D000538:Aluminum Silicates / Q000737:chemistry* / Q000378:metabolism; D031056:Amorphophallus / Q000254:growth & development / Q000378:metabolism; D001410:Bacillus megaterium / Q000302:isolation & purification / Q000378:metabolism; D001412:Bacillus subtilis / Q000302:isolation & purification / Q000378:metabolism; D001419:Bacteria / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism*; D005308:Fertilizers; D006863:Hydrogen-Ion Concentration; D007194:India; D007210:Indoleacetic Acids / Q000737:chemistry / Q000378:metabolism; D050296:Microbial Viability; D008855:Microscopy, Electron, Scanning; D010758:Phosphorus / Q000737:chemistry / Q000378:metabolism; D010802:Phylogeny; D011188:Potassium / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism*; D017680:Potassium Compounds / Q000737:chemistry* / Q000378:metabolism; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D017550:Spectroscopy, Fourier Transform Infrared
D000538:Aluminum Silicates; D005308:Fertilizers; D007210:Indoleacetic Acids; D017680:Potassium Compounds; D012987:Soil; C016447:feldspar; D010758:Phosphorus; C030737:indoleacetic acid; D011188:Potassium
Bacillus; Elephant foot yam; KSB; Rock powder bioformulation