Insecticidal Effects of Clove (Syzygium aromaticum) and Basil (Ocimum basilicum) againstLarvae of Mosquito (Culex quinquefasciatus Say)

Abstract

The experiments were conducted in the research Laboratory, of College of Agricultural Studies (Shambat), Sudan University of Science and Technology (SUST), during May, 2019.The average temperature is between 30-35°C and relative humidity (RH) is between 30 – 35 C %. The aim of this study is to verify the effectiveness of the clove plant, Syzygium aromaticum (water and oil extract), and basil plant Ocimum basilicum, an (oil extract) , a commercial botanical oil, branded al hawag, was used. Against larvae of culex (Culex quinquefasciatus) under laboratory condition. Four different concentrations were used for each single experiment(2%, 1%, 0.50, and 0.25). in the first experiment, using clove as water extract, and in the second, using clove and basil as oil extract, plus one drop of liquid soap was added as a surfactant, and the treatment was done on the second and fourth stages of the larva of the mosquito (Culex quinquefasciatus),except for the water extract of clove in the second star only. Each treatment was replicated three times in addition to the control, and mortality % was recorded after (1, 6, 12, 24, 48, and 72 hour) respectively. The result showed different effects between extracts as well as between different stages of larva as insecticides. The water extract of clove gave mortality% (98.3%, 43.3%) the clove oil in 2th and 4th start gave (96.6%, 58.3% and 96.6%, 66.6%) respectively. And basil oil in 2th and 4th start gave (85.0%, 41.6% and 58.3%, 46.7) respectively after 72h of treatment at the highest and lowest concentration. These results confirmed that the oil extract of clove has a greater effect than the water extract, and that clove oil has a greater effect on Culex larvae than basil oil, which can be used as a source of plant insecticides in the future.