Pattanachatchai, N., Tongsanit, N. and Kongkum, N. 2026. Leaf chlorophyll content, phenolic content, flavonoid content and antioxidant activity of collard greens in response to fertilizer value of duckweed . International Journal of Agricultural Technology. 22, 5 (Sep. 2026), 2323–2342. DOI:https://doi.org/10.63369/ijat.2026.22.5.2323-2342.