Short communicationEffect on health promoting phytochemicals following seaweed application, in potato and onion crops grown under a low input agricultural system

•The effect of seaweed on yield and phytochemical content was evaluated.•A pure cold process commercial seaweed was used (A. nodosum).•Seaweed application increased total phenolic and flavonoid content.•There was a consistent increase of the phytochemical content of treated plants.

Regular consumption of fruits and vegetables is linked with a lowered risk of heart disease, cancer and stroke. Two different pilot studies were set up in Greece (potato), and Ireland (onion) to study the effect of a commercial cold process seaweed extract from Ascophyllum nodosum on the yield and phytochemical content of potato and onion. Results from this study indicated that there was an increase in phenolic and flavonoid content in onion while in potato significant differences were detected only in flavonoid content. There were no statistically significant differences in yield in either crop, although seaweed treated potato plants had higher yields. These results indicate the potential of seaweed extracts in increasing the phytochemical content of vegetables.