title: Construction of a hypervirulent and specific mycoinsecticide for locust control.
abstract: Locusts and grasshoppers (acridids) are among the worst pests of crops and grasslands worldwide. Metarhizium acridum, a fungal pathogen that specifically infects acridids, has been developed as a control agent but its utility is limited by slow kill time and greater expense than chemical insecticides. We found that expression of four insect specific neurotoxins improved the efficacy of M. acridum against acridids by reducing lethal dose, time to kill and food consumption. Coinoculating recombinant strains expressing AaIT1(a sodium channel blocker) and hybrid-toxin (a blocker of both potassium and calcium channels), produced synergistic effects, including an 11.5-fold reduction in LC50, 43% reduction in LT50 and a 78% reduction in food consumption. However, specificity was retained as the recombinant strains did not cause disease in non-acridids. Our results identify a repertoire of toxins with different modes of action that improve the utility of fungi as specific control agents of insects.
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou. 310058, Zhejiang, China.
authors.forename: Weiguo
authors.initials: W
authors.lastname: Fang
authors.affiliation: Department of Entomology University of Maryland College Park MD 20742 USA.
authors.forename: Hsiao-Ling
authors.initials: HL
authors.lastname: Lu
authors.affiliation: Division of Chemical &Structural Biology Institute for Molecular Bioscience The University of Queensland St. Lucia, QLD 4072 Australia.
authors.forename: Glenn F
authors.initials: GF
authors.lastname: King
authors.affiliation: Department of Entomology University of Maryland College Park MD 20742 USA.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: St Leger
mesh_terms: D000818:Animals; D024861:Genetic Enhancement / Q000379:methods*; D006110:Grasshoppers / Q000382:microbiology* / Q000502:physiology*; D052981:Metarhizium / Q000502:physiology*; D009498:Neurotoxins / Q000235:genetics* / Q000378:metabolism; D010572:Pest Control, Biological / Q000379:methods*; D015996:Survival Rate
chemical_list: D009498:Neurotoxins