crw1 - A Novel Maize Mutant Highly Susceptible to Foliar Damage by the Western Corn Rootworm Beetle

Abstract

Western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is the most destructive insect pest of corn (Zea mays L.) in the United States. The adult WCR beetles derive their nourishment from multiple sources including corn pollen and silks as well as the pollen of alternate hosts. Conversely, the corn foliage is largely neglected as a food source by WCR beetles, leading to a perception of a passive interaction between the two. We report here a novel recessive mutation of corn that was identified and named after its foliar susceptibility to corn rootworm beetles (crw1). The crw1 mutant under field conditions was exceptionally susceptible to foliar damage by WCR beetles in an age-specific manner. It exhibits pleiotropic defects on cell wall biochemistry, morphology of leaf epidermal cells and lower structural integrity via differential accumulation of cell wall bound phenolic acids. These findings indicate that crw1 is perturbed in a pathway that was not previously ascribed to WCR susceptibility, as well as implying the presence of an active mechanism(s) deterring WCR beetles from devouring corn foliage. The discovery and characterization of this mutant provides a unique opportunity for genetic analysis of interactions between maize and adult WCR beetles and identify new strategies to control the spread and invasion of this destructive pest.

Decreased Polysaccharide Feruloylation Compromises Plant Cell Wall Integrity and Increases Susceptibility to Necrotrophic Fungal Pathogens

“…Since modification of cell wall composition, and specifically reduction of FA, may affect plant-pathogen interactions ( Venkata et al, 2013 ), we next used pathogen infection to challenge the transgenic Arabidopsis generated previously ( Pogorelko et al, 2011 ) and the Brachypodium plants generated in this study. We measured the susceptibility of Arabidopsis plants expressing AnFAE and wild-type Col-0 plants by inoculating leaves with B. cinerea conidia and evaluating symptoms 48 h post inoculation (hpi).…”

Chitinase-like1 Plays a Role in Stalk Tensile Strength in Maize

“…For lignin, 2 mg of the dried-stalk cell wall, ground to a fine powder, was used for acetyl bromide-soluble lignin (ABSL) analysis following the published protocol of Fukushima et al (1991) with slight modifications made by Venkata et al (2013). In brief, the cell wall material was dissolved in 100 mL of freshly made acetyl bromide/acetic acid solution (20:80, v/v) in a 20-mL volumetric flask.…”