title: Induced epidermal permeability modulates resistance and susceptibility of wheat seedlings to herbivory by Hessian fly larvae.
abstract: Salivary secretions of neonate Hessian fly larvae initiate a two-way exchange of molecules with their wheat host. Changes in properties of the leaf surface allow larval effectors to enter the plant where they trigger plant processes leading to resistance and delivery of defence molecules, or susceptibility and delivery of nutrients. To increase understanding of the host plant's response, the timing and characteristics of the induced epidermal permeability were investigated. Resistant plant permeability was transient and limited in area, persisting just long enough to deliver defence molecules before gene expression and permeability reverted to pre-infestation levels. The abundance of transcripts for GDSL-motif lipase/hydrolase, thought to contribute to cuticle reorganization and increased permeability, followed the same temporal profile as permeability in resistant plants. In contrast, susceptible plants continued to increase in permeability over time until the entire crown of the plant became a nutrient sink. Permeability increased with higher infestation levels in susceptible but not in resistant plants. The ramifications of induced plant permeability on Hessian fly populations are discussed.
authors.affiliation: USDA-ARS Crop Production and Pest Control Research Unit, MWA, West Lafayette, IN 47907, USA. Christie.Williams@ars.usda.gov
authors.forename: Christie E
authors.initials: CE
authors.lastname: Williams
authors.forename: Jill A
authors.initials: JA
authors.lastname: Nemacheck
authors.forename: John T
authors.initials: JT
authors.lastname: Shukle
authors.forename: Subhashree
authors.initials: S
authors.lastname: Subramanyam
authors.forename: Kurt D
authors.initials: KD
authors.lastname: Saltzmann
authors.forename: Richard H
authors.initials: RH
authors.lastname: Shukle
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D004175:Diptera / Q000502:physiology*; D016002:Discriminant Analysis; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D060434:Herbivory / Q000502:physiology*; D006867:Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D007814:Larva / Q000502:physiology; D008969:Molecular Sequence Data; D015999:Multivariate Analysis; D009499:Neutral Red / Q000378:metabolism; D010539:Permeability; D059828:Plant Cells / Q000378:metabolism; D019441:Plant Epidermis / Q000166:cytology / Q000502:physiology*; D018515:Plant Leaves / Q000166:cytology / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000469:parasitology*; D013194:Staining and Labeling; D013997:Time Factors; D014908:Triticum / Q000201:enzymology / Q000469:parasitology*
chemical_list: D012333:RNA, Messenger; D009499:Neutral Red; D006867:Hydrolases