Three PhD studentships available in my lab, studying different aspects of flower development and pollinator attraction. First closing date is 1 December. Contact me direct to discuss: Professor Beverley Glover at bjg26@cam.ac.uk.or see details below:
PhD Project 1 at Glover Group: Iridescence in flowers – how and why?
Supervisor: Professor Beverley Glover
Brief Summary: This project aims to understand how and why some flowers produce iridescent, angle-dependent colours on their petals.
Importance of Research
The enormous species diversity of the angiosperms was described by Darwin as “an abominable mystery”. Part of the explanation lies with the ways in which different plant species are reproductively isolated from one another, as a result of divergence of floral morphology and consequent differences in their interactions with pollinating animals. This project aims to understand a novel way in which flowers attract insect pollinators: the production of iridescent colours using nanoscale sculpturing of the petal surface.
We will explore how an iridescent flower develops, and how a naturalised iridescent weed interacts with native pollinator species. This project will not only be important in understanding plant-pollinator interactions, but may also inform approaches to generate structurally coloured materials for a range of applications.
Project Summary
This project aims to understand both how and why some flowers produce iridescence. Iridescence occurs when the colour of a surface appears different when that surface is viewed from different angles, and can only be produced using structural methods, not pigments.
You will study the mechanisms by which iridescence is generated, using molecular genetic techniques in our model system Hibiscus trionum. Hibiscus trionum is a naturalised weed across much of Europe and North America. We will assess which pollinator species interact with it in 2 European field locations. We will then use mutants generated from the molecular development work to explore how the presence of iridescence influences those interactions.
What will the successful application do?
Your project will focus on identifying the genetic basis of floral iridescence and assessing how it contributes to pollination in Hibiscus trionum.
- We are conducting a mutant screen to identify genes involved in the formation of cuticular folds which generate iridescence in Hibiscus trionum. We have already identified 2 mutant lines with reduced iridescence. You will continue to screen for new mutants, conduct genetic and phenotypic characterisation of mutant lines, and use bulk segregant analysis to identify mutated genes.
- Hibiscus trionum is native to tropical and subtropical regions of the Old World, but has naturalised across Europe and North America. We do not know what pollinates it. You will identify and quantify floral visitors and true pollinators in replicated field plots in Cambridge and in southern Europe.
- You will conduct a field trial in Cambridge to compare pollinator response to wild type Hibiscus trionum and non-iridescent mutants from the mutant screen.
- You will characterise the function of genes identified from the mutant screening and bulk segregant analysis using transgenic approaches in H. trionum.
Training Provided
The student will be given training in fieldwork analysing pollinator visitation and behaviour, including insect identification. In the lab they will learn light microscopy and scanning electron microscopy, in genetic analysis of trait development, DNA/RNA extraction, Illumina sequencing, PCR, cloning, expression analysis (including quantitative RT-PCR) and plant transformation.
References
- Moyroud, E., Wenzel, T., Middleton, R., Rudall, P.J., Banks, H., Reed, A., Mellers, G., Killoran, P., Westwood, M.M., Steiner, U., et al. (2017). Disorder in convergent floral nanostructures enhances signalling to bees. Nature
PhD Project 2 at Glover Group: Optimising pollination of vicia faba for enhanced crop yield and to support biodiversity:
Supervisors
Professor Beverley Glover (University of Cambridge)
Dr Tom Wood and Dr Jane Thomas (NIAB)
Dr Roger Vickers and Dr Becky Howard (PGRO)
Background
Pollination is an essential part of the production of our food supply. Ensuring an adequate supply of pollinators is essential to maintain global food security but pollinator populations have declined in many parts of the world, and it is likely that climate change will further uncouple relationships between plants and insects. Crop flowers themselves can provide an important component in the nutrition of wild insect pollinators, contributing significantly to maintenance of biodiversity in agricultural landscapes.
However, almost no attempt has been made to analyse the relationships between crops and pollinators, or to assess how it could be improved to the benefit of both yield and biodiversity. We propose to explore this system with respect to the UK field bean crop. Recent reports suggest that pollination service is limiting yields in field beans. In those areas of the UK where field beans are grown they may represent one of the few significant nectar sources for foraging insects in agricultural landscapes.
Our approach will be to explore strategies for optimising field bean flowers to provide maximum energetic reward to pollinators for minimum foraging energy expenditure. We will also investigate the effect of flower-rich margin plantings on bean pollination, considering their role both as traps of herbivorous bruchid beetle and as supporters of wild pollinators.
Objectives and Approaches
We will use a combination of analytical, behavioural ecology and field-based techniques to explore strategies to enhance pollination. Field trials will be conducted at NIAB and on the PGRO trial sites.
Objectives:
1. Identification of breeding targets for enhanced pollination of and pollinator support by field beans
Our previous work has identified substantial variation between commercially grown field bean lines in traits relevant to pollinator reward and pollinator attraction. Preliminary field trials conducted on the PGRO trial site revealed that some of this variation is associated with enhanced pollinator visitation rate to the crop and enhanced yield. We will unpick these relationships further, to identify targets for breeding field bean varieties that optimally support insect pollination. We will analyse the traits of commercial faba bean flowers that influence pollinator attraction, including reward, visual and scent traits.
We will explore the effect of these traits on foraging bumblebees using our bee behavioural laboratory. This study will provide us with a detailed understanding of which features make a field bean flower most attractive to bees. In combination with our previously published work on variation in field bean floral reward, this workpackage will provide breeding targets to optimise field beans as pollinator attractants and supporters of wild pollinator populations.
2. Assessment of the effect of flower-rich field margins on field bean pollination
Our preliminary field trials at PGRO revealed that flower-rich field margins contain substantially increased pollinator diversity and much higher numbers of pollinators than bean crops themselves. It is not clear whether this is an advantage to farmers, in that the wild flower strips bring in pollinators which will also service the crop, or a disadvantage, in that the wild flower strips draw pollinators away from the crop.
We will conduct field trials, planting replicated field bean plots with and without flower rich margins. Sweep netting will be used to provide snapshots of insect diversity within the flower rich margins and the crop plots at specified time points. Pollinator observation data will be collected in the bean plots, recording types and numbers of visitors across whole days. In the final year a replicated plot trial will be set up as before at PGRO but harvested after use, to compare yield in plots with and without wild flower strips.
Primary location of the PhD
This PhD will be based at the Department of Plant Sciences, University of Cambridge and registered with the University of Cambridge
Training
Students will have access to training opportunities through their University to complement their scientific development. This will be augmented by training in key bioscience areas such as statistics through the CTP-SAI.
The project will provide training for the student in morphological and biochemical analysis of flowers, including microscopy and GC-MS; bee behavioural experiments; field trial design; insect identification and recording; data handling and statistics. They will receive additional training in presentation and communication skills, small grant writing, paper writing and project planning.
There will be additional skills training to enhance employability and research capability. All CTP-SAI students will receive Graduate Training in Leadership and Management from MDS. Additionally, students will create their Personal Development Plan (PDP) to identify their development needs and areas of strength. Each student will receive individual coaching and mentoring pertinent to their career plans and skills development in addition to the scientific project supervision.
Industrial Placement
Placements are a key feature of CTP and UKRI-BBSRC expects all doctoral candidates on a CTP programme to undertake a placement. Placements can be in the form of research placements (3-18 months duration) or used more flexibly for experiential learning of professional skills for business and/or entrepreneurship. All placements are developed in collaboration between the partners with input from the doctoral candidate.
Application and Eligibility
The student will be registered with the University of Cambridge and based in the Department of Plant Sciences.
Contact Professor Beverley Glover (bjg26@cam.ac.uk) for an informal discussion on the research content of this PhD.
Beginning in October 2022, the successful candidate should have (or expect to have) an Honours Degree (or equivalent) with a minimum of 2.1 in Plant Science, Applied Statistics, or other related science subjects. Students with an appropriate Masters degree are particularly encouraged to apply.
We welcome UK, EU, and international applicants. Candidates whose first language is not English must provide evidence that their English language is sufficient to meet the specific demands of their study. Candidates should check the requirements for each host organization they are applying to, but IELTS 6.5 (with no component below 6.0) or equivalent is usually the minimum standard.
This studentship is for four years and is fully funded in line with UKRI-BBSRC standard rates. These are:
An annual maintenance stipend of £17,668, fee support of £4,596, a research training support grant of £5,000 and conference and UK fieldwork expenses of £300.
To be classed as a home student, candidates must meet the following criteria:
- Be a UK National (meeting residency requirements), or
- Have settled status, or
- Have pre-settled status (meeting residency requirements), or
- Have indefinite leave to remain or enter
If a candidate does not meet the criteria above, they would be classed as an international student and must demonstrate the ability to meet the supplement in fees required for an international student.
Anyone interested should complete the online application form before the deadline of 1st December 2022. Interviews will be held during January 2022.
Please contact recruitment-ctp-sai@niab.com for further application details.
PhD Project 3 at Glover Group: Spurring evolution: understanding the development and diversification of nectar spurs:
Supervisor
Beverley Glover
Brief Summary
This project aims to understand the evolution and development of nectar spurs, because they drive reproductive isolation and speciation in both plants and insects, but their development is very little studied.
Importance of Research
The enormous species diversity of the angiosperms was described by Darwin as “an abominable mystery”. Part of the explanation lies with the ways in which different plant species are reproductively isolated from one another, as a result of divergence of floral morphology and consequent differences in their interactions with pollinating animals. Nectar spurs are outgrowths of the flower, usually of a petal, that either produce nectar or hold nectar that is secreted elsewhere.
Only a pollinating insect with a proboscis as long as the spur can access the nectar contained in it. Long-spurred flowers are therefore pollinated by different insects than short spurred flowers. Separation of plants within a family into reproductively isolated groups with different spur lengths and different pollinators results in rapid speciation. Therefore understanding spur evolution and development is central to understanding angiosperm radiation and also provides underpinning data to help manage plant and insect communities.
Project Summary
This project aims to understand the evolution and development of nectar spurs, because they drive reproductive isolation and speciation in both plants and insects. Because no conventional molecular genetic model plant species produces nectar spurs, we know very little about the molecular genetic control of their development. You will explore this developmental genetic problem in the genus Linaria, which has species with a very wide range of nectar spur lengths. This range of spur lengths allows us to take a comparative and evolutionary approach. Fieldwork will be focused on analysing how spur length influences which pollinators interact with a flower.
What will the successful application do?
This project will combine molecular genetic and comparative morphological approaches to analyse spur length evolution, along with detailed field studies to analyse how spur length influences pollinator visitation.
- Conduct a mutant screen to identify mutants of Linaria vulgaris with altered nectar spur development. Use bulk segregant analysis to identify the genes controlling nectar spur development.
- Conduct field trials with mutants with altered nectar spurs to compare types of pollinators, pollinator numbers and behaviour in response to alterations in spur morphology. Linaria vulgaris is widespread in Europe but the role of its spurs in restricting pollinators is unknown.
- Explore the detailed function of the genes you identify by expression analyses and transgenic approaches in Linaria vulgaris.
- Compare development of closely related Linaria species with different spur lengths, assessing how expression profiles of your key genes are associated with differences in nectar spur length.
Training Provided
The student will be given training in fieldwork analysing pollinator visitation and behaviour, including insect identification. In the lab they will learn light microscopy and scanning electron microscopy, in genetic analysis of trait development, DNA/RNA extraction, Illumina sequencing, PCR, cloning, expression analysis (including quantitative RT-PCR) and plant transformation.
References
- Cullen E, Fernández-Mazuecos M, Glover BJ. Evolution of nectar spur length in a clade of Linaria reflects changes in cell division rather than in cell expansion. Ann Bot. 2018 Nov 3;122(5):801-809
If you’re interested in joining the Evolution and Development Group please contact Professor Beverley Glover directly at bjg26@cam.ac.uk. Informal applications from students who wish to study for a PhD in the Evolution and Development Group are always welcome, contact Professor Beverley Glover for an informal discussion of opportunities. Prospective postgraduate students are required to apply through the University’s Applicant Portal. For information on how to apply, including course entry requirements, deadlines and application fees, visit the Postgraduate Admissions website. Any available PhD projects are listed above.