author(s)
Mahmoud Osanloo, Amir Amani, Hassan Sereshti, Mansoureh Shayeghi and Mohammad Mehdi Sedaghat

abstract
In this study larvicidal activity of extracted essential oil of Kelussia odoratissima (KO) and its major component i.e. Z-ligustilide (LIG) were evaluated against Anopheles stephensi and compared with together during May 2016. Yield of extraction of essential oil from KO was 0.1% from dried plants. Components of essential oil were identified by GC-MS analysis. Z-ligustilide (64.24%), 2-octen-1-ol acetate (7.17%), thymol (4.72%), E-ligustilide (4.42%) and eugenol (2.51%) were 5 major components of KO. Larvicidal tests were performed in line with WHO guideline. Calculated LC₅₀ and 90% for LIG (i.e. 8.73 and 15.70 ppm) higher than total essential oil (i.e. KO: 4.77 & 8.44 ppm). Essential oil has more effective than its major components and beside that, has low cost and lower risk in occurrence of resistance in different population of mosquito larvae.