Biofortification and antioxidant improvement of onion bulbs using calcareous algae and storage

[...]onions present well-known benefits to health and are among the main vegetable crops grown worldwide. [...]the objective this work was to evaluate the effects of foliar sprays with micronized Lithothamniun sp. on yield, mineral nutrients, flavonoids, phenolic content, and antioxidant activity before and after storage of bulbs of two organically grown onion cultivars. [...]its antibacterial, anti-inflammatory, and antioxidant activities have been widely investigated (Zamri & Hamid, 2019). [...]onions are part of our diet, not only for their flavor but for their functionality in the human body (Marrelli et al., 2019). The depositions of calcareous algae at the bottom of the ocean could follow organic matter transformation, similar to that in the soil, where the algae organic fraction is being transformed into bioactive humic substances, promoting plant growth and yield (Amatussi et al., 2020). MATERIAL AND METHODS Growing conditions and plant material Onion plants were grown in the Organic Vegetables Research Area, in an organic system since 2006, at the Federal University of Paraná, Paraná State, Curitiba, Brazil., under the geographical coordinates 25°25'S and 49°06'W and altitude of 920 m. The climate, according to the Köppen's classification, is subtropical of the Cfb type.