Potato Review

www.potatoreview.com POTATO REVIEW MARCH/APRIL 2023 39 CUPGRA “ e second phase of HIP was building mutual understanding between the partners, and adopting an interdisciplinary approach with targeting the application of research which is focused on improvement of the quality, yield and e ciency in cultivations, logistics and processing potatoes.” “We are now working to secure the continuation of HIP until 2033 by building on the requirements of our partners, which include interdisciplinary research, governance, control and the interdependency of the di erent sub-sectors of our industry.” Building more in-depth understanding of breeding for PCN resistance Not enough is known about PCN resistance genes in potato, said Sebastian Eves-van den Akker from the Crop Science Centre, a partnership between the University of Cambridge and NIAB. Although the default state of the plant is resistant, there may be a susceptibility gene which is activated. To create a resistant variety, the susceptibility gene could be switched o , or a resistance gene added, but nding these genes is more di cult than it sounds. Sebastian said: “To breed for resistance, we have to start by phenotyping the infection, looking at the roots and counting and measuring the nematodes, assessing howwell they are doing and howmany eggs they are likely to lay.” To achieve this, Sebastian teamed up with Ji Zhou fromNIAB to solve the phenotyping problem in Arabidopsis, which is susceptible to nematodes, as a proof-of-principle. He explained that, as roots are underground, and there is a need to scale capacity to count the nematodes, he and his team decided to use petri-dishes as they are easier to view both roots and nematodes. ey also developed their own custom hardware with a link to arti cial intelligence to count the nematodes visible in each dish. “We measured nematode number, size, opaqueness, colour (which shows progression through its life-cycle) and were able to track their growth and development through time. e aim is to provide information which can help growers pick the variety to grow in particular conditions. “Our initial ndings also indicate that if you can slow the development of the nematode and then harvest the crop before it nishes its life-cycle, you can stop infection in its tracks.” Research to understand sources of blackleg inoculum Free living nematodes (FLN) in the soil can cause root damage which may provide an important pathway to blackleg infection in potato crops, revealed Prof Ian Toth of the James Hutton Institute who held a workshop at the CUPGRA event. Recent work in collaboration with the University of Dundee has revealed that damaged root zone becomes packed with bacteria between one and two days after the damage has been caused. e bacteria colonise the root as it grows and the pathogen is able to move into the haulm, said Ian. Although PCN can be found in the root, no similar e ects on blackleg have been observed. Ian is also working with the University of Durham to obtain data on varietal susceptibility and resistance to blackleg. “If we can identify chemical signals connected with resistance, they can then be used as markers in breeding,” he said. “So far, our colleagues in Durham have identi ed two chemicals in root exudates. ese may play an important role in future breeding programmes.” Further research in conjunction with the University of Glasgow is looking at the potential of microbial populations being used in defence of the plant. He said the blackleg pathogen Pectobacterium can produce proteins called bacteriocins which kill their close relations. Research is underway to discover whether these bacteriocins could protect against infection in a similar way to our Innovate UK-funded work on bacteriophages with APS Biocontrol. e research is being funded by Scottish Government, Defra, BBSRC and NERC through the Bacterial Plant Diseases Programme. Ian said: “We are very excited about the new lines of evidence that our multi- partner research project has identi ed, and we envisage that some of these lines will begin to make a tractable di erence to the potato industry in the near future.” Sprout suppression – understanding how to get the best from available options Recent changes in products available for sprout suppression, including the introduction this year of DMN (1,4SIGHT®), were of great interest to conference delegates. e potato industry now has a number of di erent in-store application options to choose between: Spearmint oil (Biox-M), orange oil (Argos), ethylene and 1,4DMN, plus maleic hydrazide (MH) which is applied in the eld. As a result, many in the industry are taking advantage of the wider availability, and are assessing what works best for them. Storage specialist Adrian Cunnington of Potato Storage Insight who, along with co-presenter Sarah Roberts from NIAB CUF, held a workshop on dormancy and evaluating the new sprout control options, said there is a lot to learn about the timings and sequencing of these di erent products. An early dormancy break encouraged quite a few store managers to trial 1,4 DMN and he noted enthusiasm around the product, but reminded everyone it is not a complete replacement for CIPC. ➜ Hertfordshire farmer Stuart Roberts. Adrian Cunnington of Potato Storage Insight. Bernard de Geus of Holland Innovative Potato.