UTTAR PRADESH JOURNAL OF ZOOLOGY

Mosquito-borne diseases remain a major public health concern, particularly in tropical and subtropical regions, creating a continued need for effective and sustainable vector-control approaches. Plant-based repellents offer a potentially affordable and environmentally compatible alternative to conventional synthetic mosquito-control products. This study evaluated plant-based mosquito repellents prepared as coils and incense sticks from locally available botanical materials: Cymbopogon citratus leaves, Eucalyptus globulus leaves, Citrus maxima peel, and Isodon ternifolius leaves. The selected plant parts are traditionally used by local communities as insect repellents. Each botanical material was processed separately, and a combined formulation containing all four materials was also prepared. Burning performance, repellency, knockdown, and 24-hour mortality were assessed against laboratory-reared adults of Culex quinquefasciatus, Aedes aegypti, and Anopheles longirostris under controlled chamber conditions. All formulations burned completely, with residual ash values ranging from 38.76% to 41.09%. Repellency generally increased with exposure time. Among the individual formulations, lemongrass and khoiju showed comparatively greater repellent activity, while pomelo peel and eucalyptus showed moderate activity. The combined botanical formulation produced the highest overall repellency among the plant-based treatments and caused 46.6% mortality after 24 hours. The synthetic coil used as the positive control produced 93.3% mortality, whereas the untreated negative control produced no mortality. These findings indicate that the selected botanical materials produced measurable repellent and knockdown effects under laboratory conditions, although their lethal activity was lower than that of the synthetic coil. Further work should standardise formulation ratios, characterise active compounds, assess smoke safety, establish adequate replication, and evaluate performance under field conditions.