Discovering the genetic drivers for host resource allocation between symbionts

点击翻译按钮获取中文摘要

Plants interact with a wide range of different organisms, many of which feed from plant tissues in order to survive. Some of these interactions can be mutually beneficial, such as arbuscular mycorrhizal fungi (AMF) that obtain plant resources to fuel their development whilst also contributing nutrients to their host. On the other hand, plants can also interact with parasites, such as plant-parasitic nematodes. These are microscopic animals that are dependent on plants as food sources and provide no reciprocal benefits. Plants will likely simultaneously interact with both of these organisms as over half of the plant species that are hosts to plant-parasitic nematodes are also host to an AMF species. Both symbionts must compete for the finite amount of host resources (such as sugars and lipids) that are on offer by manipulating mechanisms within the host plant to direct resources towards themselves. Such mechanisms are increasingly defined for single symbiont-host interactions, however there is a lack of research on how multiple, concurrent symbionts may impact resource allocation mechanisms. This new knowledge would have wide implications for the relevance of research in natural systems. My preliminary work for this proposal provides strong evidence that a host plant expresses genes that may facilitate the movement of resources to certain regions of its root system, based upon its spatial interactions with symbionts. With this Fellowship, I will differentiate the mechanisms by which a plant can allocate its resources to beneficial and detrimental symbionts, as well as those mechanisms that are common to both. This has important implications for future efforts to tailor the allocation of resources between detrimental and beneficial symbionts, which may have the potential to boost crop yields and aid food security efforts. By combining a range of techniques I will manipulate a select number of the genes involved in these mechanisms to disrupt resource allocation and outline the impacts on symbiont fitness. I will integrate an above-ground parasite into my system to reveal common mechanisms that result in resource losses to parasites and more faithfully represent natural ecosystems. This will allow comparisons between the mechanisms that above- and below-ground parasites utilise to gain access to their food sources. This knowledge will provide the opportunity for a new suite of control measures, whilst considering their potential impacts on beneficial organisms.