Cereal aphids differently affect benzoxazinoid levels in durum wheat

PLoS One. 2018 Dec 3;13(12):e0208103. doi: 10.1371/journal.pone.0208103. eCollection 2018.

Abstract

Aphids are major pests in cereal crops that cause direct and indirect damage leading to yield reduction. Despite the fact that wheat provides 20% of the world's caloric and protein diet, its metabolic responses to aphid attack, in general, and specifically its production of benzoxazinoid defense compounds are poorly understood. The objective of this study was to compare the metabolic diversity of durum wheat seedlings (Triticum turgidum ssp. durum) under attack by three different cereal aphids: i) the English grain aphid (Sitobion avenae Fabricius), ii) the bird cherry-oat aphid (Rhopalosiphum padi L.), and iii) the greenbug aphid (Schizaphis graminum Rondani), which are some of the most destructive aphid species to wheat. Insect progeny bioassays and metabolic analyses using chromatography/Q-Exactive/mass spectrometry non-targeted metabolomics and a targeted benzoxazinoid profile were performed on infested leaves. The insect bioassays revealed that the plants were susceptible to S. graminum, resistant to S. avenae, and mildly resistant to R. padi. The metabolic analyses of benzoxazinoids suggested that the predominant metabolites DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin- 3-one) and its glycosylated form DIMBOA-glucoside (Glc) were significantly induced upon both S. avenae, and R. padi aphid feeding. However, the levels of the benzoxazinoid metabolite HDMBOA-Glc (2-hydroxy-4,7-dimethoxy-1,4-benzoxazin-3-one glucoside) were enhanced due to the feeding of S. avenae and S. graminum aphids, to which Svevo was the most resistant and the most susceptible, respectively. The results showed a partial correlation between the induction of benzoxazinoids and aphid reproduction. Overall, our observations revealed diverse metabolic responses of wheat seedlings to cereal aphid feeding.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aphids / pathogenicity
  • Aphids / physiology*
  • Benzoxazines / analysis
  • Benzoxazines / metabolism*
  • Biological Assay
  • Disease Resistance / physiology
  • Edible Grain / metabolism
  • Edible Grain / parasitology
  • Glucosides / analysis
  • Glucosides / metabolism
  • Host-Parasite Interactions / physiology*
  • Nymph
  • Plant Diseases / parasitology*
  • Plant Leaves / metabolism
  • Plant Leaves / parasitology
  • Reproduction / physiology
  • Species Specificity
  • Triticum / metabolism
  • Triticum / parasitology*

Substances

  • 2-hydroxy-4,7-dimethoxy-1,4-benzoxazin-3-one glucoside
  • Benzoxazines
  • Glucosides
  • 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one

Grants and funding

This research was funded by Bona Terra Foundation Fund for Promoting Sustainable Agriculture in Drylands for RS and ZB, and by The Ministry of Science and Technology in Israel, Women in Science Scholarship for RS.