Title:

Implications of Toxic Cyanobacteria in Green Manure Microbiomes

The use of chemical soil fertilizers, while aimed at enhancing agricultural crop growth and yield, proves to be highly inefficient, leading to significant loss from soils. The result is downstream nutrient runoff, causing pollution of both terrestrial and aquatic environments, including aquatic blooms and increased soil acidity. To reduce excessive nutrient runoff, chemical fertilizers could be replaced by green manure plants, such as duckweeds, grown in runoff detention ponds on farms. Consequently, nutrients would be applied to crops in a closed-loop system rather than the continuous addition of synthetic chemicals, reducing environmental harm caused by runoff. However, toxic cyanobacteria present in green manure microbiomes may pose human health risks if contaminated produce is consumed. Though the implementation of green manures would provide a sustainable agriculture solution, the risk of toxic cyanobacteria in the duckweed microbiome must first be assessed to understand potential human health implications associated with green manure crops. In a green house experiment, results suggest that green manures increased lettuce growth compared the control treatments (no green manure added). Additionally, green manures were equally toxic across source ponds, and microcystin concentration in lettuce was consistent across treatments and green manure sources. Finally, effects on lettuce were similar across green manure sources despite differing microbiomes, where various genera of toxin-producing cyanobacteria were identified in the green manure microbiomes.

Name

Comment*

Comments are viewable only by submitter

Captcha*