TITLE:
Effect of Trichoderma koningiopsis on Chickpea Rhizosphere Activities under Different Fertilization Regimes
AUTHORS:
Ashmita Tandon, Touseef Fatima, Anshu Gautam, Udit Yadav, Suchi Srivastava, Poonam C. Singh
KEYWORDS:
Soil Enzymes, Organic Acids, Rhizosphere Remodeling, Integrated Nutrient Management
JOURNAL NAME:
Open Journal of Soil Science,
Vol.8 No.10,
October
30,
2018
ABSTRACT: Interaction of plant growth promoting microorganisms (PGPMs) with plants
involves interplay at physical, physiological and molecular levels. Proliferation
and root colonization of PGPMs manipulate the rhizosphere to optimize
plant functions. This benefits plant by nutrient enrichment and induction of
plant vigor and defense system. The present work aims to decipher the rhizosphere
modulations promoted under different fertilization regimes by an
organic acid producing Trichoderma koningiopsis strain (NBRI-PR5).
Chickpea was selected as the host plant for the study since it responds well to
the application of in/organic fertilizers and PGPMs. Microbial communities
associated with the rhizosphere were studied by determining culturable population
of heterogeneous microflora, and rhizosphere functions were studied
by determining the soil enzyme activities and HPLC profiles of organic acids
in root exudates. Application of NBRI-PR5 induced changes in rhizosphere in
consent with the amendments. The changes observed in microbial populations
were found to be associated with the rhizosphere enzymes. The inhibitory
effect of chemical fertilizers on rhizosphere microflora was evident from
least bacterial CFU observed in the NPK treatments. No detection of alkaline
phosphatase enzyme in all the treatments with NBRI-PR5, with organic or
inorganic amendments evidently represents the acidified rhizosphere. Similarly,
an opposite trend in DHA and protease enzyme activities in the rhizosphere
of FYM and FYM+PR5 treated plants showed that NBRI-PR5 had reframed
microbial activities to facilitate nutrient uptake in plants rather than
fix in the microbes. It is concluded from the study that NBRI-PR5 fatefully
modulates rhizosphere activities, specific to different fertilization regimes by
varying the enzyme activities to maximize the utilization of available nutrients.