Abstract
The transport and fate of PGPB in soil is affected by soil and water
properties (e.g., soil particle size distribution and surface
properties, water content, organic matter content etc.) and bacteria's
surface characteristics (e.g., surface charge, hydrophobicity, cell size
and shape etc.). When implemented to the root zone via subsurface or
surface water source, some PGPB may die naturally or non-naturally
(e.g., toxicity of low water quality). We hypothesized that live and
dead PGPB have different surface properties, thereby their transport and
retardation in soil will exhibit different characteristics. Azospirillum
brasilense is commonly employed as a PGPB that can produce of
phytohormones and fix nitrogen. In this study, two A. brasilense strains
(Cd and Sp7) were used in a flow through soil column transport
experiment under saturated conditions. The strains were applied with
different ratios of live and dead bacteria. The established breakthrough
curves (BTC) of live, dead bacteria and their mixture were different.
The live bacteria moved faster than dead bacteria. For example, after a
pulse input (10 pore volumes) of bacteria suspension (100% live or 100%
dead bacteria), the recovery of live bacteria in the leachates was 12
38% higher than dead bacteria. Competitive adsorption isotherms, contact
angle, zeta potential and fluorescence microscopy observation were used
to explain the measured BTCs. The results of this study will be
presented and their implications for PGPB inoculation in the root-zone
will be discussed.
| Original language | English |
|---|---|
| Title of host publication | EGU2019, Proceedings held 7-12 April, 2019 in Vienna, Austria, id.17359 |
| Pages | 17359 |
| Volume | 21 |
| State | Published - 1 Apr 2019 |
| Event | 21st EGU General Assembly, EGU2019 - Vienna, Australia Duration: 7 Apr 2019 → 12 Apr 2019 |
Conference
| Conference | 21st EGU General Assembly, EGU2019 |
|---|---|
| Country/Territory | Australia |
| City | Vienna |
| Period | 7/04/19 → 12/04/19 |