PLEASE NOTE: Application deadline date 08 Jan 2024. Applications are no longer being accepted for this project
Project Overview
The diamondback moth (DBM) is a global specialist pest of Brassica crops. Caterpillar feeding shows daily rhythmicity controlled both by environmental light and circadian clocks. This project will identify how DBM herbivory is jointly determined by environmental factors as well as molecular responses in both pest and plant.
Project Description
The diamondback moth (DBM), Plutella xylostella, causes >$5 billion in annual damages worldwide by impacting brassica agriculture. Its unique glucosinolate sulfatase (GSS) enzymes allow it to evade the glucosinolate/myrosinase defence system of cruciferous plants1. The expression of DBM GSS genes exhibits daily rhythmicity and is impacted by light as well as the internal timekeeping of both pest and host plant. This project aims to describe how DBM herbivory is jointly determined by environmental and biological factors. This will be approached by testing how host glucosinolate production and DMB herbivory are impacted by 1) natural and disrupted environmental cycles in light and temperature and 2) host plant mutations affecting defence pathways. Glucosinolate levels and DBM herbivory will be determined for various light/temperature cycles under both lab and field conditions. These experiments will cover lab simulations of UK conditions with and without added impacts of light pollution and global warming as well as long day and short day field conditions to follow up on the observation that glucosinolate production is restricted during short days3. Genetic experiments will make use of the model cruciferous plant Arabidopsis thaliana to employ mutants that may affect DBM herbivory via their impact on glucosinolate biosynthesis2 and other plant defence pathways. RNAseq analyses of both DBM caterpillars and host plants will be conducted for conditions known to impact glucosinolate levels and/or herbivory to identify associated changes in gene expression across different environmental contexts.
The INSPIRE DTP programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered at the University of Southampton and hosted at the School of Biological Sciences as well as at the CASE partner organization (Royal Horticultural Society in Wisley). Specific training will include: plant (Brassica and Arabidopsis) and insect (DBM) culture; herbivory assays; extraction and chromatographic quantification of glucosinolates; RNAseq analysis of DBM caterpillars and host plants; bioinformatics and statistical data analysis; oral and written presentation skills; attendance of national and international research conferences and participation in outreach and engagement activities.
[1] Furlong MJ, Wright DJ, Dosdall LM. Diamondback moth ecology and management: problems, progress, and prospects. Annu Rev Entomol. 2013;58:517-541. doi:10.1146/annurev-ento-120811-153605
[2] Fernández-Calvo P, Iñigo S, Glauser G, et al. FRS7 and FRS12 recruit NINJA to regulate expression of glucosinolate biosynthesis genes. New Phytol. 2020;227(4):1124-1137. doi:10.1111/nph.16586
[3] Harun S, Abdullah-Zawawi MR, Goh HH, Mohamed-Hussein ZA. A Comprehensive Gene Inventory for Glucosinolate Biosynthetic Pathway in Arabidopsis thaliana. J Agric Food Chem. 2020;68(28):7281-7297. doi:10.1021/acs.jafc.0c01916
