Chang, Ting-WeiTing-WeiChangMasui, NoboruNoboruMasuiHirano, TakashiTakashiHiranoNyawai, Tiara NalesTiara NalesNyawaiRahman, MustaqimMustaqimRahmanAbdullah, Meilina OngMeilina OngAbdullahTani, AkiraAkiraTani2026-01-152026-01-152025-1113522310https://www.scopus.com/record/display.uri?eid=2-s2.0-105012400002&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/735380Oil palm (Elaeis guineensis) is known for its substantial isoprene emissions, which can contribute to air pollution and climate change. As oil palm plantations expand across Southeast Asia, developing effective mitigation strategies such as propagating low-isoprene-emitting variants of this species is essential. To this end, we measured the isoprene emissions from oil palm saplings grown from seeds and clonally propagated under controlled environmental conditions in an E. guineensis nursery in Sessang, Malaysia. The effects of the leaf position, time of day, root conditions, and growth stage were examined for further data quality control. The first set of results showed that isoprene emissions varied more widely in seed-derived saplings (mean: 13.6 ± 5.2 nmol m−2 s−1) than in clonal saplings (mean: 18.6 ± 2.9 nmol m−2 s−1), with the latter exhibiting consistently higher emissions. Further investigation of the potential influencing factors revealed that isoprene emission rates varied with leaf position, with the upper and middle fronds producing more isoprene than lower fronds. Additionally, the emissions exhibited clear peaks in the morning or midday. Older trees exhibited significantly higher isoprene emission rates (26.32 ± 6.49 nmol m−2 s−1) than saplings, suggesting that the emissions change with growth stage. Based on these findings, we recommended that isoprene emission measurements be taken from the middle or upper leaves in the morning or at midday to ensure a reliable comparison. The substantial intraspecific variability in isoprene emission among E. guineensis saplings from crossbreeding highlights the potential for identifying and selecting low-emission variants.falseAir qualityBiogenic organic compoundsPollution mitigationTropical forest[SDGs]SDG2journal article10.1016/j.atmosenv.2025.1214692-s2.0-105012400002