Pest and pathogen detection and monitoring

Pest and pathogen populations and epidemiology

Free Living Nematode Diagnostics

Crop damage due to FLNThere are numerous species of microscopic Free-Living Nematodes (FLN) that affect hundreds of crops globally directly through root feeding that results in reduced yields or indirectly through transmission of viruses that impact quality of produce. Plant pathogenic species of FLN are primarily ectoparasitic root feeders though some species, known as semi endo-parasitic, will briefly enter the host crop. Thus, unlike other groups of plant feeding nematodes, like potato cyst nematodes, typically FLN undertake no significant part of their life cycle within a host plant. FLN also comprise of a range of feeding groups which are considered beneficial to soils: bacteriovores, fungivores, omnivores and predators. FLN typically occur in discrete patches therefore it is unusual for nematode related problems to be uniform across fields.

Insect Pest Collections

Culturing collected insect material allows the preservation of live reference collections and provides insect material for research. 

Our insect cultures are held in dedicated insect-rearing rooms which provide appropriate environment control. In addition, we use controlled environment cabinets to maintain insect cultures in duplicate and to provide flexibility to vary environmental conditions at different stages of insect life cycles.

The aphid culture collections comprise different genotypes of the peach-potato aphid Myzus persicae including insecticide-susceptible and -resistant clones. Some of these lineages date back many years and the oldest was collected in 1977. The collection includes almost all of the main 17 genotypes that have been found in the UK for the last 20 years. Most of these clones have now ceased to exist in the field. The responsibility of maintaining this unique aphid material is shared with Rothamsted Research. M. persicae has a worldwide distribution and is a vector of many economically-important plant viruses.

Insect Cultures leaflet


Predictive diagnostics to underpin IPM of soil-borne potato diseases

Powdery scab on a potato tuberSoil-borne pathogens of potato cause a number of serious blemish diseases.  By employing appropriate soil sampling strategies in conjunction with a method for soil DNA extraction and real-time PCR assays to detect and quantify target pathogens, we can validate the relationship between soil-borne inoculum and disease risk. The relationship between pathogen detection and disease risk for black dot (Lees et al. 2010 and Brierley et al. 2015) and powdery scab (Brierley et al. 2012) have been determined. Furthermore, the impact of soil-borne inoculum on disease has been investigated in conjunction with other control factors such as host resistance and crop management, for example, crop duration and chemical control (Brierley et al. 2018).

Blackleg on Potato

Blackleg on potato stemsBlackleg (including soft rot) of potato is a devastating disease for which there are no chemical treatments. Disease control is particularly important for the seed potato industry as the pathogen, once present, increases in population through seed generations. Since the 1960s, disease has been controlled by ventilated storage, seed certification, good hygiene and more recently by managing seed imports (safe haven scheme and Government legislation). While disease incidence is much reduced than 50 years ago, it still remains a major problem both in Europe and beyond.  Over the last 5 years blackleg disease appears to be on the increase although the reasons for this are not clear.  At the Institute we are focussing on 4 control measures to be included in the blackleg IPM strategy.