2022 年 13 巻 1 号 p. 164-168
Botanical insecticides may offer an alternative solution for pest control. The objective was to test on the repellant, contact, and fumigant effect of the essential oils of 10 indigenous plants from Khok Phutaka Resources Protection Area, Khon Kaen Province including Limnophila aromatica, Piper sarmentosum, Clausena harmandiana, Streptocaulon juventas, Litsea glutinosa, Thunbergia laurifolia, Eupatorium odoratum, Rothmannia wittii, Ficus altissima, Clausena harmandiana and Gymnopetalum integrifolim to control the rice weevil, S. oryzae. The essential oils of plants were extracted by using hydro-distillation method and then they were tested against rice grain weevil, S. oryzae for contact, fumigant and repellent activities in laboratory condition. Adults of weevil were different tested oil at the concentrations of 0, 25, 50, 75 and 100 percentage (w/v). The maximum repellency action, 80% when L. glutinosa oil, at the concentrations of 100% (w/v) were applied for after 72 hours follow by L. aromatica (73.33%) at the concentrations of 25% (w/v) were applied for after 2 hours. The fumigant and contact test of all 10 essential oils resulted in all lower rate mortality (less than 50%), at all the concentrations.
