The value of seed and ware potato crops is reduced by a range of aphid transmitted viruses. These viruses are collectively known as ‘persistent’ and ‘non-persistent’ viruses. Persistent viruses can only be transmitted by species of aphid that settle on potato plants, such as the peach-potato aphid (Myzus persicae). Meanwhile, non-persistent viruses can be transmitted by both colonising and non-colonising aphids, such as the pea aphid (Acyrthosiphon pisum).
Growers use certified seed with low levels of virus, however, production of sufficient high-quality certified seed has become more difficult in recent years with withdrawal of key insecticides. This situation has been compounded by development of widespread resistance to remaining insecticides in both colonising and non-colonising virus vectors.
‘Push-pull’ is a crop protection method in which an intercrop or repellent is applied to the crop (‘push’) and a highly attractive trap crop is grown around the main crop, which acts as a lure for the pest (‘pull’). When effectively applied this approach minimises damage to the crop and concentrates the pest in field margins where natural enemies are more numerous where flowering strips are used.
Several candidates for inclusion in a ‘push-pull’ system for virus vectors of potato crops are already known but their effectiveness is currently unknown.
OBJECTIVES AND APPROACHES
Objective 1: Confirm positive behavioural responses, e.g. landing behaviour, of each species of aphid to one or more potential trap crops – this part of the project would be completed under laboratory (olfactometer and wind-tunnel) and glasshouse conditions and use a selected range of widely grown potato varieties. Year 1
Objective 2: Confirm negative behavioural responses, e.g. landing behaviour, of each species of aphid to one or more plant essential oils and/or companion crops – as above, this part of the project will be completed under laboratory (olfactometer and wind-tunnel) and glasshouse conditions and use a selected range of widely grown potato varieties. Years 1 & 2
Objective 3: Investigate aphid landing behaviour within prototype push-pull systems. This part of the project will be completed under laboratory (wind-tunnel), glasshouse and field conditions (semi-field and commercial conditions), working with colleagues at NIAB and CUPGRA to secure suitable sites. Years 2 & 3
Objective 4: Optimise push-pull systems e.g. modifying plant mixes within trap crop, spatial arrangement of trap crop plants, use of novel formulations of plant essential oils (nano-formulations and microencapsulation technologies) as repellents. Year 3
Objective 5: Field evaluation of optimised push-pull system under commercial conditions working with colleagues at NIAB and CUPGRA to secure suitable sites. Recording aphid numbers and virus transmission within crops. Years 3 & 4
PRIMARY LOCATION OF THIS PHD
This PhD will be based at and registered with Harper Adams University.
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.
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 (www.mds-ltd.co.uk). 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.
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
Contact Dr Tom Pope for an informal discussion on the research content of this PhD.
Beginning in October 2023, the successful candidate should have (or expect to have) an Honours Degree (or equivalent) with a minimum of 2.1 in Plant Science, Zoology, 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.
Anyone interested should complete the online application form before the deadline of 6th January 2023. Interviews will take place at the end of January/beginning of February 2023.
Please contact [Email Address Removed] for further application details.