Potato Cyst Nematode (PCN) was the topic of the afternoon at this new technical event held this July at the family farm of John Reid at Newmill of Balgavies, near Forfar. PCN was identified as one of the top five issues facing the industry as a whole during Potato Council’s 2013 “Direction through Dialogue” discussions throughout 2013.Welcoming the large audience of growers and industry to the event, Alistair Redpath, Chief Executive of PseedCo, leading seed growers and member of the QV group gave a sobering overview of the threat of ‘PCN creep’ to our industry.Alistair told the large audience that “Scotland has around 11,000 hectares of seed production in 2014 and exports from Scotland are a significant contributor to the Scottish economy. If the rate at which we are losing seed land in Angus were to be “rolled out” across Scotland as a whole and nothing else changes, by 2020 we will have less that 7,500 hectares of seed production in Scotland.”
The line-up of expert talks started with Dr Jon Pickup from SASA examining the impact that the new EU PCN Directive has had in Scotland, highlighting that with the soil sampling rate increasing, there has been an increase of over 2-fold in the land area recorded as infested with PCN. The highest incidence of PCN is found in Angus – over 5 times higher than it is in the northern counties of Scotland – and the relative intensity of potato production is the most likely explanation for this situation. However, there is considerable variation in the incidence of infestations - even within Angus.Jon stressed that improved approaches to PCN management are needed to preserve enough PCN-free land for seed production, particularly for Angus growers. Jon highlighted Potato Council’s online PCN Calculator www.potato.org.uk/online-toolbox/pcn-calculator, simple to use and a key management tool that can help growers make informed decisions about PCN management strategies. Jon concluded, in tune with other experts on the day, that resistant varieties which have provided a key tool for managing populations of Globodera rostochiensis, are now required to control an increasing Globodera pallida problem, alongside rotation and soil treatments.Dr Daan Kiezebrink looked at the potential of brassica bio-fumigant crops – radish and mustards – to control PCN populations in the soil. Daan highlighted the Potato Council-funded R&D work on bio-fumigants, which is independently evaluating the potential of bio-fumigants in controlling PCN to communicate to levy payers. Daan stressed that “It is important to produce enough biomass for bio-fumigants to be effective. You need to flail the bio-fumigant crop to release the active gases before rotavating into the soil soon after flailing, and then to seal it. This will help make the bio-fumigants more effective, and if you can combine the flailing and rotivating procedures, so much the better”, advised Daan.Darryl Shailes of Hutchinsons looked at how precise soil sampling protocols can help gain a clear picture of PCN in your fields, and how you can best identify the higher and lower areas of PCN counts using a 1ha grid sampling system. Darryl believes this to be the most cost-effective sampling intensity rate, which also offers possibilities of part-field treatments by identifying areas with lower population counts.The Soil Pest Management Initiative (SPMI) is a project underway to develop and promote best practice in the safe and efficient management of soil-borne pests. This group is developing a sampling protocol which will allow growers to sample soils effectively and obtain a clear picture of the PCN situation in their fields. Echoing others, Darryl explained that the key to control of PCN was to sample and map it effectively, to select the right variety, to choose and apply soil treatments carefully and always follow stewardship guidelines.During the afternoon’s sessions, Agrico’s Archie Gibson talked about how, by increasing awareness and use of PCN-resistant and tolerant varieties, you could meet product specifications whilst keeping seed and ware land in production, thus reducing dependency on nematicides.Staffordshire grower, James Daw, who grows for Walkers and McCain, gave an overview of the precision farming work he does in his potato operations. James stressed that with costs rising, the information he gains from precision farming technology – and the specific field data it gives him - helps him to adjust his inputs accordingly, reduce his risks and increase his marketable yield.“We need to go back to basics” advised James. “To look at what we do and to measure the effects of any changes we make. I am working with CUF who measure the outcomes and value of the precision farming work I do. By adjusting how I plant and grow my crop, I can achieve a more uniform crop and also gain other benefits such as a reduction in water usage and seed costs.”Dr Denise A’Hara of SASA updated growers on the detail of the proposed new EU seed classification scheme and the options available for Scottish implementation. Growers were able to discuss the options in detail with Denise and feedback their thoughts in preparation for the meeting with UK industry stakeholders and government departments in August, which will refine the options in preparation for the consultation period that will follow.Denise also took the opportunity to discuss the planned SASA trials work to examine the possible causes of blackleg in Pre-Basic (PB) seed crops and asked growers for their help with providing PB material for the studies.Host farmer John Reid showed visitors around the farm, providing a detailed overview of their operations and their potato crops in particular. At Vinny Farm, they grow 70% ware for Albert Bartlett and 30% seed for ware growing and for export. They test around 40% of their land and this year, 100% was passed. They use a standard 7-year rotation, clean machines down between fields, grow once-grown seed only from PCN-free land and can utilise steep and stony land previously considered unsuitable for growing potatoes. Currently they have no visual symptoms of PCN infestation.Following the talks and discussions, growers left the farm reporting that they would change, or consider changing their working practices relating to PCN, with comments such as “I would carry out more voluntary PCN sampling” and “[I have a] better understanding of the UK picture” being just a small sample of remarks made.Current Potato Council-funded PCN research includes projects to update the on-line management model on the potential risks from second generations of PCN within the same season (as summer temperatures increase); to more fully understand the dynamics of within-field populations and the effects of varietal resistances and tolerances; and to fully investigate the agronomy and benefits of trap crops and bio-fumigation as alternative means of PCN control. Potato Council has been able to leverage significant additional funding - over and above grower and industry levies - from Scottish Government and from Defra’s HAPI and Agri-Tech Strategy funding initiatives.GB’s largest technical field event for potatoes is coming up soon. Potatoes in Practice, sponsored by Potato Council, and free to attend, will be held on Thursday 7th August at The James Hutton Institute’s Balruddery Farm, near Dundee. Around 1000 industry visitors are expected, where they will see science in practice, variety trial and demonstration plots, live working machinery, the new harvesting clinics, practical seminars and trade stands.