Nutrient-specific foraging and the role of spiders as biocontrol agents.
Lead Research Organisation:
Cardiff University
Department Name: School of Biosciences
Abstract
Spiders are major predators of aphids (and other pests) in cereal crops and are an essential element of pest control in low-input and organic agriculture. However, their economic value to farmers is affected by their density and relative predation rates on pest and non-pest insects. It has been demonstrated in the lab that predators can exercise nutrient-specific foraging to balance their diets (Mayntz et al., Science 2005). Thus, if they have been eating sugar-rich aphids they may preferentially increase predation on protein-rich Collembola or flies.
Spiders cannot survive on aphids alone and agriculturalists require guidance on the need to preserve non-aphid prey within crops. However, nutrient-specific foraging has never been demonstrated in the field. Our aim will be to compare what is available to the spiders with what the spiders have eaten. Major nutrients will be analysed for common prey (e.g. Hawley et al., PlosOne 2014). We will analyse diets of spiders using molecular methods then compare what is available with what is eaten, looking for deviations from random feeding that balance their nutrient intake.
Mesocosm experiments, informed by prey densities in the field and spider diets, will confirm whether nutrientspecific foraging, rather than other factors, is regulating prey choices.
First rotational project - Morphological and molecular identification. This PhD requires expertise in the taxonomy and molecular identification of the species involved. Identification of spiders and 'difficult' prey groups will require training. Relevant species will need DNA barcoding. Training in these areas will primarily be in the lab of WOCS, assisted by JRB at Rothamsted (spiders) and taxonomists in the National Museum of Wales.
Second rotational project - Analysis of prey nutrients. A major element within the PhD will be analysis of the effects of major nutrients on prey choice. The student will learn how to conduct the biochemical analyses needed, supervised by CTM. S/he will analyse relevant species from arable fields, establishing their nutrient content and the effects of crop and season.
Spiders cannot survive on aphids alone and agriculturalists require guidance on the need to preserve non-aphid prey within crops. However, nutrient-specific foraging has never been demonstrated in the field. Our aim will be to compare what is available to the spiders with what the spiders have eaten. Major nutrients will be analysed for common prey (e.g. Hawley et al., PlosOne 2014). We will analyse diets of spiders using molecular methods then compare what is available with what is eaten, looking for deviations from random feeding that balance their nutrient intake.
Mesocosm experiments, informed by prey densities in the field and spider diets, will confirm whether nutrientspecific foraging, rather than other factors, is regulating prey choices.
First rotational project - Morphological and molecular identification. This PhD requires expertise in the taxonomy and molecular identification of the species involved. Identification of spiders and 'difficult' prey groups will require training. Relevant species will need DNA barcoding. Training in these areas will primarily be in the lab of WOCS, assisted by JRB at Rothamsted (spiders) and taxonomists in the National Museum of Wales.
Second rotational project - Analysis of prey nutrients. A major element within the PhD will be analysis of the effects of major nutrients on prey choice. The student will learn how to conduct the biochemical analyses needed, supervised by CTM. S/he will analyse relevant species from arable fields, establishing their nutrient content and the effects of crop and season.
Organisations
Publications
Bajwa A
(2019)
Assessment of nematodes in Punjab Urial (Ovis vignei punjabiensis) population in Kalabagh Game Reserve: development of a DNA barcode approach
in European Journal of Wildlife Research
Lafage D
(2019)
A new primer for metabarcoding of spider gut contents
in Environmental DNA
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| BB/M009122/1 | 01/10/2015 | 31/03/2024 | |||
| 1799693 | Studentship | BB/M009122/1 | 01/10/2016 | 31/12/2020 | Jordan Cuff |
| Description | Development of molecular methods for spider diet analysis and macronutrient determination from invertebrates. The diet of spiders has been characterised, finding that they are exhibiting biocontrol of crop pests, but that the pests most consumed are thrips, indicating some potential mismanagement of spiders in agriculture as they are most often viewed as aphid predators. Prey choice in spiders switches to reflect changes in their prey availability following harvest, indicating a need for better consistent provision of spiders with suitable prey. |
| Exploitation Route | Implemented into farmland management for improved biocontrol. |
| Sectors | Agriculture, Food and Drink,Education,Environment |
| Description | British Ecological Society Travel Award |
| Amount | £500 (GBP) |
| Organisation | British Ecological Society |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 09/2017 |
| End | 09/2017 |
| Description | GCRF Network Award: A network for networks: building an interdisciplinary team to define trophic interactions underpinning predator-mediated biological control |
| Amount | £10,000 (GBP) |
| Organisation | United Kingdom Research and Innovation |
| Department | Global Challenges Research Fund |
| Sector | Public |
| Country | United Kingdom |
| Start | 03/2020 |
| End | 07/2020 |
| Description | One-off Meeting Sponsorship Grant |
| Amount | £1,000 (GBP) |
| Organisation | The Genetics Society |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 11/2017 |
| End | 11/2018 |
| Description | Wellcome Trust ISSF3 Public Engagement Grant |
| Amount | £7,425 (GBP) |
| Organisation | Wellcome Trust |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 09/2019 |
| End | 09/2020 |
| Title | PCR primers for the analysis of cereal crop money spider diet |
| Description | These PCR primers will allow analysis of the diet of cereal crop money spiders (Araneae: Linyphiidae) via DNA metabarcoding. There are currently no other such primers published and these (alongside others developed in collaboration with other groups, mentioned separately) will enable an efficient metagenomic analysis of spider diet in the field. |
| Type Of Material | Biological samples |
| Year Produced | 2018 |
| Provided To Others? | No |
| Impact | These primers have been adopted for use by one internationally recognised lab and by many existing researchers in Cardiff University. Pending publication. |
| Title | Protocol for macronutrient determination in small macroarthropods |
| Description | This protocol allows the rapid, direct and parallel determination of macronutrients from macroarthropods as small as an aphid. The protocol has been validated and applied and will be submitted for publication imminently. |
| Type Of Material | Biological samples |
| Year Produced | 2018 |
| Provided To Others? | No |
| Impact | This protocol has been adopted by three different research groups so far, with expression of interest from a broader range. |
| Title | Various other dietary PCR primers |
| Description | I have designed PCR primers for other projects including those for the analysis of the diet of ants, carabid beetles, ladybirds, wolf spiders, nematodes, otters, etc. |
| Type Of Material | Biological samples |
| Year Produced | 2019 |
| Provided To Others? | No |
| Impact | Increased accuracy of dietary analysis and eventual publishing of all primers. |
| Description | Identification and confirmation of a pseudoscorpion species new to Britain |
| Organisation | Natural History Museum |
| Country | United Kingdom |
| Sector | Public |
| PI Contribution | Barcoding of specimens to confirm identification; Contribution to final publication. |
| Collaborator Contribution | Collection and identification of specimens; Confirmation and description of specimens; Writing of final publication. |
| Impact | Publication pending. |
| Start Year | 2018 |
| Description | Investigation of the chemical cues associated with aphid vectors of barley yellow dwarf virus |
| Organisation | Rothamsted Research |
| Department | Biological Chemistry and Crop Protection |
| Country | United Kingdom |
| Sector | Charity/Non Profit |
| PI Contribution | I designed and will lead the work, including all practical and written elements. |
| Collaborator Contribution | Provision of materials and contribution to ideas. |
| Impact | We will write a paper. |
| Start Year | 2019 |
| Description | Investigation of the mechanisms underlying prey choice in social wasps |
| Organisation | Indian Institute of Science Bangalore |
| Country | India |
| Sector | Academic/University |
| PI Contribution | Concept, design, leading grant writing, organising personnel involved in the project, practical aspects. |
| Collaborator Contribution | Expertise, knowledge, access to facilities and field sites. |
| Impact | A grant has been obtained to fund a network event to build the collaboration and benefit further development of the project. The project spans trophic ecology, molecular ecology, entomology, agriculture, chemical ecology, electrophysiology and landscape ecology. |
| Start Year | 2020 |
| Description | Molecular analysis of ladybird predation upon aphids and novel PCR primers |
| Organisation | University of Zurich |
| Country | Switzerland |
| Sector | Academic/University |
| PI Contribution | In silico evaluation of PCR primers; Contribution to writing of final publication. |
| Collaborator Contribution | Experimental design; Fieldwork; Lab work; Design of PCR primers; In vitro evaluation of primers; Writing of final publication. |
| Impact | Publication in preparation. |
| Start Year | 2017 |
| Description | Spider-exclusion PCR primers for analysis of Pardosa sp. diet |
| Organisation | Karlstad University |
| Country | Sweden |
| Sector | Academic/University |
| PI Contribution | Discussion of experimental design; Testing of novel PCR primers in vitro; Sequencing of PCR products to determine success; Writing for final publication. |
| Collaborator Contribution | Full experimental design; Sample collection; Primer design; In silico testing; In vitro testing; Metabarcoding; Preparation of final publication. |
| Impact | Publication in prep. |
| Start Year | 2018 |
| Description | Spider-exclusion PCR primers for analysis of Pardosa sp. diet |
| Organisation | University of Guelph |
| Country | Canada |
| Sector | Academic/University |
| PI Contribution | Discussion of experimental design; Testing of novel PCR primers in vitro; Sequencing of PCR products to determine success; Writing for final publication. |
| Collaborator Contribution | Full experimental design; Sample collection; Primer design; In silico testing; In vitro testing; Metabarcoding; Preparation of final publication. |
| Impact | Publication in prep. |
| Start Year | 2018 |
| Description | Collaborative blog |
| Form Of Engagement Activity | Engagement focused website, blog or social media channel |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Postgraduate students |
| Results and Impact | I co-founded a blog to discuss ecological themes and questions in a broad context. This is a continuous and evolving platform. |
| Year(s) Of Engagement Activity | 2018,2019 |
| Description | Farmers' Union Talk, Wenvoe Farmers' Union |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Professional Practitioners |
| Results and Impact | Approximately 30 agricultural professionals attended, many of whom asked questions relating to the research. Some expressed, following the talk, that they had changed their views toward biological control of crop pests and invertebrates as an aspect of their farmland more generally. |
| Year(s) Of Engagement Activity | 2018 |
| Description | Green Man Festival Einstein's Garden Engagement Activity |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Public/other audiences |
| Results and Impact | Several themed activities were designed for all ages to educate the public about agriculture and the environment. I designed and led a game to teach families specifically about biological control, integrated pest management and sustainable intensification. Many questions were asked and opinions formed and debated. |
| Year(s) Of Engagement Activity | 2017,2018 |
| Description | Wellcome Trust ISSF3-funded Animal ARKS of the 21st Century: Engaging people with biobanking and species conservation |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Public/other audiences |
| Results and Impact | Engagement activities with the public in collaboration with Frozen Ark. Events and games to teach the public about the biodiversity crisis, DNA and how biobanking can help via several games and activities. |
| Year(s) Of Engagement Activity | 2019,2020 |