Data from: Biofertilizers from wastewater treatment as a potential source of mineral nutrients for growth of amaranth plants

Exploring alternative fertilizers is crucial in agriculture due to the
cost and environmental impact of inorganic options. This study
investigated the potential of biofertilizers derived from sewage treatment
on the growth and physiology of Amaranthus cruentus plants. Various
treatments were compared, including control treatments with inorganic
fertilizer and treatments with biofertilizers composed of microalgae,
biosolids and reclaimed water. The following traits were investigated:
photosynthetic pigments, gas exchange, growth, and leaf nutrient
concentrations. Results show that the concentrations of N, P, Cu, Fe Zn
and Na nutrients, in the dry microalgae and biosolids, were quite high for
the needs of the plants. The wet microalgae presented high concentration
of Cu, Fe and Zn nutrients while reclaimed water contained high
concentration of N, K, Ca and S. Na and Zn nutrients increased in the leaf
of plants treated with dry microalgae and biosolid, respectively. At the
beginning of the flowering phase, total chlorophyll and carotenoids
contents were lower for plants grown with wet microalgae while for plants
grown with higher doses of biosolid or reclaimed water total chlorophyll
was increased, and carotenoids were not affected. Lower photosynthetic
pigments under wet microalgae resulted in lower photosynthetic rates. On
the other hand, amendments with dry microalgae and biosolid increased
photosynthetic rates with the biosolid being the most effective. Higher
applications of biosolid, wet and dry microalgae produced a considerable
increase in shoot biomass of amaranth, with the dry microalgae being the
most effective. Additionally, reclaimed water obtained after tertiary
treatment of sewage with microalgae and biosolids applied alone showed
promising effects on plant growth. Overall, these findings suggest that
organic fertilizers derived from sewage treatment have the potential to
enhance plant growth and contribute to sustainable agricultural practices.