title: Toxicity and physiological effect of quercetin on generalist herbivore, Spodoptera litura Fab. and a non-target earthworm Eisenia fetida Savigny.
abstract: A novel flavonoid, quercetin, was isolated from the medicinal plant Euphorbia hirta L. through chromatography techniques including: TLC, Column chromatography, NMR and then screened for toxicity to larvae of Spodoptera litura Fab. Bioassays were used to analyze pupal weight, survival rate, fecundity, egg hatchability, population growth index, Nutritional index and histopathology of treated larvae at a range of E. hirta extract concentrations. Results of toxicity assays demonstrated that, 6 ppm of quercetin caused 94.6% mortality of second, 91.8% of third, 88% of fourth, and 85.2% of fifth instars respectively. The lethal concentrations (LC50and LC90) was calculated as 10.88 and 69.91 ppm for fourth instar larvae. The changes in consumption ratio and approximate digestibility produced a reduction in growth rates. Histopathology examinations revealed that the cell organelles were severely infected. Analyses of earthworm toxicity effects resulted in significantly lower rates compared to synthetic insecticides (chloropyrifos and cypermethrin). These results suggests that the botanical compound (quercetin), could have a part as a new biorational product which provides an ecofriendly alternative. Validation of the potential of quercetin, still needs to be demonstrated under field conditions, where formulation will be important in maintaining the activity.
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, 627 412, Tirunelveli, Tamil Nadu, India.
authors.forename: Selvaraj
authors.initials: S
authors.lastname: Selin-Rani
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, 627 412, Tirunelveli, Tamil Nadu, India. Electronic address: senthil@msuniv.ac.in.
authors.forename: Sengottayan
authors.initials: S
authors.lastname: Senthil-Nathan
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, 627 412, Tirunelveli, Tamil Nadu, India.
authors.forename: Annamalai
authors.initials: A
authors.lastname: Thanigaivel
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, 627 412, Tirunelveli, Tamil Nadu, India.
authors.forename: Prabhakaran
authors.initials: P
authors.lastname: Vasantha-Srinivasan
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, 627 412, Tirunelveli, Tamil Nadu, India.
authors.forename: Edward-Sam
authors.initials: ES
authors.lastname: Edwin
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, 627 412, Tirunelveli, Tamil Nadu, India.
authors.forename: Athirstam
authors.initials: A
authors.lastname: Ponsankar
authors.affiliation: Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, 627 412, Tirunelveli, Tamil Nadu, India.
authors.forename: Jalasteen
authors.initials: J
authors.lastname: Lija-Escaline
authors.affiliation: Post Graduate and Research Centre, Department of Zoology, Sri Parasakthi College for Women, Courtrallam, 627 802, Tirunelveli, Tamil Nadu, India.
authors.forename: Kandaswamy
authors.initials: K
authors.lastname: Kalaivani
authors.affiliation: Department of Plant Protection, Faculty of Agriculture, Saba Basha, Alexandria University, P.O.Box.21531, Alexandria, 21526, Egypt.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Abdel-Megeed
authors.affiliation: United States Department of Agriculture, U.S. Horticultural Research Laboratory, 2001 South Rock Road, Fort Pierce, FL, 34945, USA.
authors.forename: Wayne B
authors.initials: WB
authors.lastname: Hunter
authors.affiliation: Treasure Coast Chemistry Consultants, LLC 107 Lakes End Drive, Apt. B Ft. Pierce, FL, 34982, USA.
authors.forename: Rocco T
authors.initials: RT
authors.lastname: Alessandro
mesh_terms: D000818:Animals; D028481:Euphorbia / Q000737:chemistry; D060434:Herbivory; D007306:Insecticides / Q000633:toxicity*; D007814:Larva / Q000187:drug effects; D009835:Oligochaeta / Q000187:drug effects*; D011679:Pupa / Q000187:drug effects; D011722:Pyrethrins / Q000633:toxicity; D011794:Quercetin / Q000302:isolation & purification / Q000633:toxicity*; D018411:Spodoptera / Q000187:drug effects*
chemical_list: D007306:Insecticides; D011722:Pyrethrins; C017160:cypermethrin; D011794:Quercetin
keywords: Asthma-weed; Biorational insecticide; Cut worm; Earthworm toxicity; Histology; Mortality; Nutritional indices; Secondary metabolites