Plant pathogen removal by managed aquifer recharge to provide safe irrigation water

Abstract

The project AGRIMAR investigates recycling of fresh tile drainage water (TDW) via managed aquifer recharge (MAR) technology for agricultural
purposes to secure water availability. Here, the TDW is collected for storage in brackish aquifers creating a fresh water ‘bubble’ in the subsurface which
gives farmers access to sufficient fresh water to irrigate their crops even in times of drought. The TDW may contain plant pathogens which could be
present in the recycled water. To prevent the spread of crop diseases, the removal of selected plant pathogens during aquifer soil passage will be
analysed. We focus on three plant pathogenic bacteria of high economic importance, namely Ralstonia solanacearum, Dickeya solani and
Pectobacterium carotovorum. As a first experimental approach, we will study the survival of the selected plant pathogens under different representative
aquifer conditions. Subsequently, their fate during soil passage is investigated in column experiments and finally in a MAR pilot field site in the
Netherlands. The inactivation processes will be described in a mathematical model to compare the model predictions with the experimental results. We
will present the outline of the research approach and the first results of batch and column experiments on the fate of these plant pathogens under
representative subsurface conditions.