Isolation of Insecticidal Constituents from the Essential Oil ofAgeratum houstonianumMill. againstLiposcelis bostrychophilaBadonnel

Abstract

The aim of this research was to determine chemical composition and insecticidal activities of the essential oil ofAgeratum houstonianumMill. aerial parts against booklice,Liposcelis bostrychophilaBadonnel, and to isolate any insecticidal constituents from the oil. Essential oil ofA. houstonianumwas obtained by hydrodistillation and analyzed by GC-MS. A total of 35 components in the essential oil were identified. The major compounds were precocene II (62.68%), precocene I (13.21%), andβ-caryophyllene (7.92%). Based on bioactivity-guided fractionation, precocene II and precocene I were isolated and identified as the active constituents. The essential oil exhibited contact toxicity againstL. bostrychophilawith an LC50value of 50.8 μg/cm2. Precocene II (LC50= 30.4 μg/cm2) exhibited stronger acute toxicity than precocene I (LC50= 64.0 μg/cm2) against the booklice. The essential oil and the two isolated constituents also possessed strong repellent activity againstL. bostrychophila. The results indicated that the essential oil and its constituent compounds have potential for development into natural insecticides or repellents for control of insects in stored grains.

Insecticidal and Anti-juvenile Hormone Activities of Precocene II against the Grasshopper Euprepocnemis plorans plorans Charp. Orthoptera: Acrididae.

“…After treatment of 4 th instar larvae of the Asian tiger mosquito, Aedes albopictus with PI and PII, LC50 values were estimated in 41.63 μg/ml and 43.55 μg/ml, respectively [64]. LC50 of PII against the booklice Liposcelis bostrychophila was calculated in 30.4 g/cm 2 but LC50 of PI was found as 64.0 g/cm 2 [37]. LC50 of PI against the cat flea Ctenocephalides felis was estimated in 10.97 ppm [70].…”

“…However, Precocene-I (7 methoxy-2,2dimethylchromene, PI) and Precocene-II (6,7dimethoxy-2,2-dimethylchromene, PII) have been used as insect regulators by inducing symptoms of JH-deficiency in insects [28][29][30]. Consequently, this inhibition can disrupt the embryonic development, induce premature metamorphosis, and disturb the insect behavior, beside their effects as antifeedants and repellents [31][32][33][34][35][36][37]. PI and PII have been shown to halt the reproductive potential in adults of several insects by prevention of the normal vitellogenesis of the oocytes, leading to sterility [35,38,39].…”

Analysis of the Essential Oil of Illicium henryi Diels Root Bark and Its Insecticidal Activity against Liposcelis bostrychophila Badonnel

“…Moreover, compared with other essential oils in previous studies using the same bioassay, /. henryi essential oil exhibited stronger or the same level of acute toxicity against the booklice as, e.g., essential oils of Acorus calamus (25), Artemisia rupestris (21), Curcuma wenyujin (28), Foeniculum vulgare (46), Valeriana jatamansi (24), and Artemisia frigida (22), but it was less toxic than Ageratum houstonianum essential oil (29).…”

Physiological Activities of Anti-Juvenile Hormone Agents Against Insects and Their Role For Devising Fourth Generation Insecticides: A Comprehensive Review

“…They inhibit the production of sex pheromone (Bowers, 1983). Also, they have potential as antifeedants and repellents against several insect species (Khafagi, 2004;Lu et al, 2014). In most cases the physiological, but not all the behavioral effects, were reversible by JH replacement therapy (Kight, 1998;Pathak and Bhandari, 2002;Chen et al, 2005a).…”

“…However, Precocene-I (7 methoxy-2,2dimethylchromene, PI) and Precocene-II (6,7-dimethoxy-2,2-dimethylchromene, PII) have been used as insect regulators by inducing symptoms of JH-deficiency in insects (Ghosh et al, 2012). Consequently, this inhibition can disrupt the embryonic development, induce premature metamorphosis, and disturb the insect behavior including aggression, mating behavior, flight behavior, maternal defensive behavior and sexual behavior, beside their effects as antifeedants and repellents (Rankin, 1980; Physiological activities of anti-JH agents against insects Srivastava and Kumar, 1997;Kight, 1998;Khan and Kumar, 2000;Pathak and Bhandari, 2002;Khan and Kumar, 2005;Chen et al, 2005a;Ringo et al, 2005;Gaur and Kumar, 2009;Lu et al, 2014).…”