student profile: Mrs Yolanda Plowman


Thesis work

Thesis title: Environmental specificity of arbuscular mycorrhizal fungal diversity and symbiotic function

Supervisors: Michael KERTESZ , Feike DIJKSTRA

Thesis abstract:

The global human population is forecasted by the United Nations to reach 9.7 billion by 2050. This increase in the human population, along with climate change, will place substantial strain food production and consequentially the environment. The intensification of agricultural output is inevitable, yet must be done sustainably to mitigate against limiting resources. Interest in the utilisation of soil microbes in food production has risen in recent years, however a level of understanding to implement soil microbes for this purpose is limited. Arbuscular mycorrhizal fungi (AMF) have a symbiotic relationship with up to 90% of all plants and can be found colonised on plant roots within the rhizosphere. AMF operate by piercing the root cortex of host plants and produce arbuscules within the plant cells, and from here extends a lengthy and complex network hyphae into the soil. It is through this network of hyphae that AMF absorb and transport nutrients and water on behalf of their host plant. Because of this symbiosis AMF offer many benefits, namely nutrient acquisition, however they’ve also been observed to provide higher levels of resistance to pests, disease, and drought. Understanding these mechanisms, how AMF species differ in function, and how species diversity is influenced by biotic and abiotic factors, is crucial to their effective utilisation in agriculture. Yet little is known about AMF species function and the drivers behind species assemblages. This PhD project investigates the AMF species diversity in wheat rhizospheres where a number of different factors are involved, such as wheat genotype, fertilisation, tillage, and crop rotation. DNA isolated from rhizsophere samples from various treatments will be sequenced using Illumina MiSeq. Findings from these analyses will then be tested under controlled environments to draw out robust conclusions on the drivers behind AMF species diversity, and how they can be utilised for real-world applications. Knowledge gained from this PhD project will help elucidate why AMF species colonise certain plant roots, and the potential mechanism behind particular plant-fungi symbioses. Furthermore, findings from this project will provide key information for the strategic application of AMF to agricultural systems.

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