title: Arsenic hyperaccumulation in the Chinese brake fern (Pteris vittata) deters grasshopper (Schistocerca americana) herbivory.
abstract: Brake fern, Pteris vittata, not only tolerates arsenic but also hyperaccumulates it in the frond. The hypothesis that arsenic hyperaccumulation in this fern could function as a defense against insect herbivory was tested. Fronds from control and arsenic-treated ferns were presented to nymphs of the grasshopper Schistocerca americana. Feeding damage was recorded by visual observation and quantification of the fresh weight of frond left uneaten and number of fecal pellets produced over a 2-d period. Grasshopper weight was determined before and after 5 d of feeding. Grasshoppers consumed significantly greater amounts of the frond tissue, produced more fecal pellets and had increased body weight on control plants compared with grasshoppers fed arsenic-treated ferns. Very little or none of the arsenic-treated ferns were consumed indicating feeding deterrence. In a feeding deterrent experiment with lettuce, sodium arsenite at 1.0 mm deterred grasshoppers from feeding whereas 0.1 mm did not. In a choice experiment, grasshoppers preferred to feed on lettuce dipped in water compared with lettuce dipped in 1.0 mm sodium arsenite. Our results show that arsenic hyperaccumulation in brake fern is an elemental defense against grasshopper herbivory.
authors.affiliation: Horticultural Sciences Department, University of Florida, Gainesville, FL 32611-0690, USA.
authors.forename: Bala
authors.initials: B
authors.lastname: Rathinasabapathi
authors.affiliation: Entomology and Nematology Department, University of Florida, Gainesville, FL 32611-0620, USA.
authors.forename: Murugesan
authors.initials: M
authors.lastname: Rangasamy
authors.affiliation: Entomology and Nematology Department, University of Florida, Gainesville, FL 32611-0620, USA.
authors.forename: Jason
authors.initials: J
authors.lastname: Froeba
authors.affiliation: Everglades REC-Belle Glade, Belle Glade, FL 33430-4706, USA.
authors.forename: Ronald H
authors.initials: RH
authors.lastname: Cherry
authors.affiliation: Entomology and Nematology Department, University of Florida, Gainesville, FL 32611-0620, USA.
authors.forename: Heather J
authors.initials: HJ
authors.lastname: McAuslane
authors.affiliation: Entomology and Nematology Department, University of Florida, Gainesville, FL 32611-0620, USA.
authors.forename: John L
authors.initials: JL
authors.lastname: Capinera
authors.affiliation: Soil and Water Science Department, University of Florida, Gainesville, FL 32611-0290, USA.
authors.forename: Mrittunjai
authors.initials: M
authors.lastname: Srivastava
authors.affiliation: Soil and Water Science Department, University of Florida, Gainesville, FL 32611-0290, USA.
authors.forename: Lena Q
authors.initials: LQ
authors.lastname: Ma
mesh_terms: D000818:Animals; D001151:Arsenic / Q000378:metabolism* / Q000494:pharmacology*; D001673:Biodegradation, Environmental; D005247:Feeding Behavior / Q000187:drug effects*; D029624:Ferns / Q000378:metabolism*; D006110:Grasshoppers / Q000187:drug effects* / Q000502:physiology
chemical_list: D001151:Arsenic