Root microbiome response to treated wastewater irrigation

Area of Science:

• Environmental Science
• Microbiology
• Agronomy

Background:

• Freshwater (FW) scarcity is increasing globally, leading to wider use of treated wastewater (TWW) for crop irrigation.
• While TWW offers a water alternative, potential long-term impacts on soil health, plant performance, and the rhizosphere microbiome require thorough investigation.

Purpose of the Study:

• To evaluate the effects of irrigation water quality (FW vs. TWW) on soil and root microbial community structure.
• To assess the impact of TWW irrigation on edaphic properties, plant performance, and the rhizosphere microbiome in different soil types and plant species.

Main Methods:

• Comparison of soil and root microbiomes (total and active communities) of tomato and lettuce grown in two soils, irrigated with either FW or TWW.
• Analysis of soil physicochemical properties (pH, EC, K, Na, DOC) and plant biomass (fruit and shoot weight).
• Calculation of effect sizes for plant species, soil type, and irrigation water quality on microbial community structure.

Main Results:

• TWW irrigation significantly increased soil pH, EC, K, Na, and DOC compared to FW irrigation.
• TWW irrigation led to decreased plant fruit and shoot weight.
• Both plant species and irrigation water quality were dominant factors shaping root-associated microbial communities, while soil type and irrigation water quality shaped soil microbial communities.

Conclusions:

• Irrigation water quality is a major determinant of root-associated microbiome structure.
• TWW irrigation significantly alters soil properties and microbial communities, impacting the plant-soil interface.
• Understanding these microbial shifts is crucial for sustainable agriculture with TWW irrigation.