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Mineral phosphate
solubilizing bacterial community in agro-ecosystem
Niharendu Saha* and
Sunanda Biswas
AICRP on Soil Test Crop Response Correlation, Directorate of Research,
Bidhan Chandra Krishi Viswavidyalaya,
Kalyani-741235, Nadia, West Bengal, India.
*Corresponding author. E-mail:
nihar_bckv@rediffmail.com
Accepted
13 March, 2009 |
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The present
communication deals with the assessment of phosphate
solubilizing bacterial community structure across
artificially created fertility gradient with regards to N, P
and K status of soil in the experimental site. 20 randomly
phosphate solubilizing bacteria from each fertility gradient
were isolated, purified and characterized through their
insoluble mineral phosphate-source utilization patterns.
Four insoluble phosphate sources; purulia rock phosphate (PRP),
mussourie rock phosphate (MRP), crystalline iron and
aluminum phosphate were charged in basic Pikovskaia solid
medium. Growth pattern of the isolates on those phosphate
sources was recorded. Different communities utilized
different P-sources in different magnitudes.
Size of isolates of low fertility gradient showing greater
utilization efficiency towards diverse phosphate sources
gradually reduced along the gradient of fertility.
Data thus obtained from the experiment were filed to compute
community structure of phosphate solubilizing bacteria
through principal component analysis (PCA).
On the
whole, the community composition of phosphate solubilizing
bacteria
reduced
gradually under the influence of cultivation and
fertilization in different fertility gradient soils.
Key
words:
Fertility gradient, phosphate solubilizing bacteria,
insoluble phosphate utilization, principal component
analysis, community structure. |
