 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Toxic Effect of Ethiopian Neem Oil on Larvae of Cattle Tick, Rhipicephalus pulchellus Gerstaeker.) ผู้เขียน: Ismail Mohamed Handule,  นางชิตาภา เกตวัลห์, รองศาสตราจารย์ , Solomon Gebre สื่อสิ่งพิมพ์:pdf AbstractThis study was conducted to test susceptibilities of cattle tick, Rhipicephalus pulchellus Gerstaeker after exposure to neem oil. The ultimate goal was to determine the bioacaricidal activity of Ethiopian neem extract under laboratory conditions for the control of R. pulchellus larvae. The LT50 values were determined for populations from each subsequent treatment by probit analysis and significant increases (chi-square test, P>0.01) occurred from one concentration to the next. There was approximately a 5.4-fold increase in the LT50 when concentration of 40% neem oil (LT50 = 0.184) was compared to 10% neem oil (LT50 = 1.01). In addition, serial concentrations of neem oil were applied and knock down concentration (KC50) was obtained (KC50 = 13.43). Baseline information from these experiments will serve as a guide for future studies on susceptibilities of tick, R. pulchellus populations. |