Electrophysiological and behavioral responses of orange wheat blossom midge to volatile organic compounds (VOCs) emitted from preanthesis and postanthesis stages of susceptible wheat

Wednesday, November 16, 2022

2:18 PM – 2:30 PM PT

Location: Vancouver Convention Centre, Meeting Room 213

Presenting Author(s)

Chaminda De Silva Weeraddana

Postdoctoral Fellow
University of Manitoba
Winnipeg, Manitoba, Canada

Co-Author(s)

WH

Wendy Hillier

Acadia University
Wolfville, Nova Scotia, Canada
Taylor Swanburg

MSc Student
Acadia Univesrity
New Minas, Nova Scotia, Canada
NH

N. Kirk Hillier

Professor
Acadia University
Wolfville, Nova Scotia, Canada
RW

Ramya Wijesundara

Biological Technician
University of Manitoba
Winnipeg, Manitoba, Canada
CM

Curt McCartney

University of Manitoba
Winnipeg, Manitoba, Canada
TW

Tyler Wist

Agriculture and Agri-Food Canada
Saskatoon, Saskatchewan, Canada
IW

Ian Wise

University of Manitoba
Winnipeg, Manitoba, Canada
SW

Sheila Wolfe

Agriculture and Agri-Food Canada
Winnipeg, Manitoba, Canada
AC

Alejandro Costamagna

University of Manitoba
Winnipeg, Manitoba, Canada

The orange wheat blossom midge (wheat midge), Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae), is a chronic pest in wheat agroecosystems. Wheat phenology is an important factor for wheat midge oviposition, and wheat midge females prefer to lay more eggs on preanthesis than postanthesis wheat spikes. We hypothesized that wheat midge oviposition behavior is influenced by volatile organic compounds (VOCs) emitted by preanthesis and postanthesis. We examined VOCs emitted from the susceptible wheat line cv. Roblin at preanthesis and postanthesis. Results showed that wheat emitted much higher amounts of cis-3-hexenyl acetate in preanthesis than in postanthesis. Higher amounts of 2-tridecanone, 2-pentadecanone and 2-undecanone were emitted in postanthesis. These key VOCs were assayed using GC-EAD (Gas Chromatography-Electroantennographic Detection) to determine the relative sensitivity of wheat midges. Wheat midge females were sensitive to all of these VOCs, suggesting that wheat midge antennae may detect changing concentrations in these key VOCs emitted at different wheat phenological stages. Behavior of adult females were examined using a vertical Y tube olfactometer. Females were attracted more to wheat spikes in preanthesis than in postanthesis. Females were attracted to cis-3-hexenyl acetate, but were deterred from 2-tridecanone and 2-pentadecanone relative to solvent control. This study will help to screen wheat lines that have deterrent VOCs in preanthesis in similar levels as susceptible postanthesis wheat.