Abstract

Microalgal biomass may have biostimulating effects on plants and seeds due to its phytohormonal content, and harnessing this biostimulating effect could contribute to sustainable agriculture. Two Nordic strains of freshwater microalgae species Chlorella vulgaris and Scenedesmus obliquus were each cultivated in a photobioreactor receiving untreated municipal wastewater. The algal biomass and the supernatant after algal cultivation were tested on tomato and barley seeds for biostimulating effects. Intact algal cells, broken cells, or harvest supernatant were applied to the seeds, and germination time, percentage and germination index were evaluated. Seeds treated with C. vulgaris, in particular intact cells or supernatant, had up to 25 percentage units higher germination percentage after 2 days and an overall significantly faster germination time (germinated on average between 0.5 and 1 day sooner) than seeds treated with S. obliquus or the control (water). The germination index was higher in C. vulgaris treatments than in the control for both tomato and barley, and this was observed for both broken and intact cells as well as supernatant. The Nordic strain of C. vulgaris cultivated in municipal wastewater thus shows potential for use as biostimulant in agriculture, adding novel economic and sustainability benefits.

Published in

Scientific Reports
2023, Volume: 13, number: 1, article number: 3509
Publisher: NATURE PORTFOLIO

SLU Authors

• Alling, Teodor

  • Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences
    

• Gentili, Francesco

  • Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

SDG6 Ensure availability and sustainable management of water and sanitation for all
SDG2 End hunger, achieve food security and improved nutrition and promote sustainable agriculture


UKÄ Subject classification

Water Treatment


Publication identifier

DOI: https://doi.org/10.1038/s41598-023-30707-8

Permanent link to this page (URI)

https://res.slu.se/id/publ/126063