Agriculture Reference
In-Depth Information
discovery of new microorganisms with unique capacities for bioremediation, soil
restoration, and therapeutic applications.
7.5.10 BOX-PCR-Based Genotypic Analysis
Naik et al. (
2008
) evaluated genetic and functional diversity of phosphate-
solubilizing fluorescent pseudomonads associated with rhizospheric soils of rice
and banana by an array of in vitro assays, gene amplification techniques, fermen-
tation methods, and chromatographic analyses. Taxonomic affiliation of bacteria
was done on the basis of
16S rRNA
gene similarity and molecular phylogenetic
analyses. These strains were taxonomically described as different fluorescent pseu-
domonad species such as
P. monteilli
,
P. putida
,
P. plecoglossicida
,
P. fluorescens
,
P. fulva
,
P. monteilli
, and
P. aeruginosa
on the basis of
16S rRNA
gene sequencing
and subsequent molecular phylogeny analysis. Phenotypic analyses as well as
16S
rRNA
and BOX-PCR-based genotypic analyses revealed a high degree of diversity
among PSB reported in this study. Meyer et al. (
2013
) used MRPP (Multiple
Response Permutation Procedure) to examine potential impacts of plant production
procedure, plant age, and sampling year on the diversity of the
Pseudomonas
communities colonizing wheat roots, based on their DGGE profiles (presence/
absence matrices of individual replicates and frequency matrices of pooled repli-
cates). Additionally, to analyze relationships between diversity-based genotype
number and factors such as plant line, replicate (block) effect, plant age, field
season, plant production procedures, and damage level (vandals damage), a gener-
alized linear model (glm) was fitted on the number of pqqC genotypes/bands
present per plant sample.
7.6 Conclusion and Future Prospects
The fragile agroecosystem is burdened with the responsibility of enhanced agricul-
tural production from a steadily decreasing and degrading land resource in the
present global scenario. Current strategies to improve the agricultural productivity
via high-input practices have placed considerable emphasis on reliable techniques
for each component of the production sequence with little consideration to the
integration of these components in a holistic, systems approach. Improvement in
agricultural sustainability requires optimal use and management of soil fertility and
soil physical properties, both of which rely on soil biological processes and soil
biodiversity. In this context, the long-lasting challenges in soil microbiology are
development of effective methods to know the types of microorganisms present in
soils and to determine functions which the microbes perform in situ. The soil
conditions need to be mimicked “in vitro” during isolation and screening of the
phosphate solubilizers, and the compatibility and abundance of introduced bacteria
