Multi-functional Nitrogen Fixing, Phosphate Solubilizing and Potassium
Solubilizing Isolates from Flood Affected Regions of Kerala
Abstract
A study was under taken to isolate and screen selected beneficial
microbes, which can restore soil fertility in the chosen flood-affected
areas of Attapady and Nelliyampathy in Palakkad district of Kerala,
India. A total of 76 isolates (40 N-fixers, 26 P-solubilizers and 10
K-solubilizers) were obtained from the flood affected areas. Triple
enzyme activities of cellulase, laccase and dehydrogenase were recorded
in 47.36% of N-fixers from Attapadi, 36.36% P-solubilizers and 60%
K-solubilizers from Nelliyampathy. Six diverse maximal enzyme producers
were selected based on study of microbial dry weight and plant
growth-promoting characteristics, including nitrogen(N) fixation,
phoshphate(P), potassium(K), and indole acetic acid(IAA) synthesis.
These 6 isolates were ranked according to all the evaluated
characteristics using statistical analysis, and the top 3 isolates were
found. The most efficient multi-functional N-fixer was identified as
Priestia megaterium from Attapadi which ranked first, Aspergillus
terreus as the most capable P-solubilizer from Nelliyampathy and
Talaromyces pinophilus as the most proficient K-solubilizer from
Nelliyampathy. The competence of these three isolates from flood
affected regions could help in the rejuvenation of the soil organic
matter (SOM) in degraded soils. However further evaluation under field
conditions are required to confirm these results.