Laconsay, Rennie Boy M.Dotarot, Stephany D.Elias, Rona D.Lumanog, Vico U.Reyes, Jhona M.2025-05-292025-05-292023-05Laconsay, R.M., Dotarot, S.D., Elias, R.D., Lumanog, V.U., Reyes, J.M. (2023). Phytoconstituents and in vitro antifungal activity of Areca catechu, Macaranga tanarius and Saribus sp. against Pyricularia oryzae [Unpublished Undergraduate Thesis]. Don Mariano Marcos Memorial State University - North La Union Campus, Sapilang, Bacnotan, La Union. Lakasa ti Sirib, DMMMSU Institutional Repository.https://lakasa.dmmmsu.edu.ph/handle/123456789/80Rice blast accounts for 10-30% of rice yield losses annually. This study reported the phytoconstituents in the leaves of Areca catechu, Macaranga tanarius., and Saribus sp. through phytochemical screening. Also, a food poisoning technique was conducted to investigate the crude extracts' antifungal activity against the rice blast fungus Pyricularia oryzae. Plant samples contained significant amounts of polyphenolic compounds and varying amounts of alkaloids, flavonoids, and tannins. While analysis showed that all treatments had inhibitory activity on the normal growth of P. oryzae, different concentrations showed varying results. And among concentrations, treatments A50, A75, A100, M75, M100, and S100 were found not statistically different from the standard fungicide. On average, crude extracts from the three plants demonstrated an almost equal activity (PI = 82.58± 1.26%), which were not statistically different.