BP2017: latest technical updates from potato event

Tuber blight incidence causes concern

More data is needed to assess and respond to the threat posed by the Dark Green 37 blight strain, which has shown resistance to fluazinam.

David Nelson, field director, Branston said more understanding of the Dark Green 37 strain was needed. “It is the biggest challenge in blight control since metalaxyl resistance in the 1980s. We don’t understand it really and need to collect information in the next 12 months. We need a lot more blight scouts.

“I have seen more incidence of tuber blight this year than since 2012. Normally you get tuber blight when you get lots of blight and can’t spray. This year growers were able to spray but is was not that effective.”

Apart from 2012, over the last 20 years Dr Nelson said, from the packing side, he had rarely seen tuber blight. “Perhaps we have not recognised the benefit we were getting from fluazinam. People were getting control relatively cheaply with fluazinam.”

A reduction in efficacy of fluazinam could put pressure on a limited number of alternatives and is likely to make blight control programmes more expensive, said Dr Nelson.

Simon Leak, marketing and development country manager for Belchim, who acquired blight fungicide Shirlan, which contains fluazinam, from Syngenta said: “Initially there was a knee jerk reaction to the 37 strain and fluazinam but we don’t know the full picture yet. Everyone is waiting for further information.

“There is still a place for fluazinam but we will have to adapt. No more back to back applications and not solo.”

For potato crops destined for storage, Belchim will not support use of fluazinam for the last three sprays of a blight control programme, says Mr Leak, however, it has a place earlier in the season, he says. “We must be careful not to have a knee-jerk reaction and throw everything away. There is a lack of AIs and modes of action.”

Actives loss concern

Loss of glyphosate could limit land availability for growing potatoes, warned Paul Colman, technical director, Greenvale AP. “It is a critical herbicide for controlling volunteer potatoes. Landowners renting out land may make the decision they don’t want potatoes in the rotation anymore.”

He also expressed concern about the impact loss of diquat could have on controlling tuber size. “This is more important for the fresh market than processing.”

Rhizoctonia fungicide launched

BASF has launched an SDHI fungicide, Allstar (fluxapyroxad) for control of rhizoctonia in potatoes. The active is also available for use in cereals.

BASF campaign manager Matthew Goodson said: “It produces brighter, more uniform potatoes with fewer skin blemishes, making them more widely marketable.”

Allstar is kind to crops, he added. “This is useful when you want to get the crop out sooner.”

Smooth flow formulation technology also makes it easy to apply, said Mr Goodson. “It is stable in dilution with smooth flow characteristics to minimise wear and reduce blockages.”

Root knot nematode field test

Fera has been working with OptiGene to develop an in-field diagnostic test to distinguish between different species of root knot nematode to help inform management decisions.

Fera senior nematologist Tom Prior said symptoms such as chlorosis (leaf yellowing) could sometimes be mistakenly attributed to drought. “Nematodes feed on the root causing galls to form which affects the plant’s ability to take up nutrients and water.

“Certain [root knot nematode] species could be controlled with rotation but if we find polyphagous species they can infest lots of hosts, are very difficult to control with rotation and chemical sterilisation may be of benefit.”

Diagnosis of these nematodes so far has involved sending samples to a lab with it taking weeks to get results back, however, the new in-field test means results can be available in an hour, said Mr Prior.

Fera is working with agronomy companies to perfect the technology, which can also be used to test for other pathogens and pests.

New nematicide under development

Bayer is developing a new liquid nematicide which can be applied in different ways.

Edward Hagues, Bayer campaign manager for roots said the product would be able to be applied overall and incorporated or in furrow. “It is a highly flexible product. It is easy to apply and has a very low dose rate. We are anticipating approval for 2019.”

Irrigation aid

PeKacid, a highly acidic, soluble phosphorous and potassium fertiliser aimed at keeping irrigation drippers or holes open, particularly where water is hard, has been launched.

ICL senior agronomist Scott Garnett said: “Our trials show that in four applications, using PeKacid can save 10 hours and 45 minutes in the irrigation process, an average of 2.75 hours per irrigation.”

Although with a low pH of 2.2, the acid is non-aggressive, he added. “We are talking to companies about its potential to extend the life of irrigation systems.”

Awards

Jim Aitkin, senior agronomist at Branston won AHDB’s Above and Beyond Award. For the last 12 years he has mentored young agronomists. The late Mark Pettigrew won AHDB’s Industry Award. He was European sustainability manager at Pepsico until his death in September. Mr Pettigrew reduced the environmental impact - in terms of CO2 and water use - of Pepsico by 50 per cent over a five-year period, said Sophie Churchill, chair of the AHDB Potatoes board, who presented the awards.

Using technology to tackle the labour challenge

Within the potato industry, one of the biggest concerns regarding Brexit is the potential loss of overseas labour which currently makes up a large proportion of the workforce for many producers and processors.

However, speakers at BP2017 suggested there was plenty of opportunity to reduce reliance on labour through the use of current technologies. Among the technologies discussed were automated graders, drone mapping, to help inform management decisions, and robotics.

Mark Taylor, business unit director of International Procurement and Logistics, said: “It is about working smarter not harder – in the future I envisage having fewer staff, but staff which are better qualified and better skilled. I will also be looking for more automation which is quite sad in some ways because it will mean taking people out of our business."

Claire Lewis, of Agri-EP, said: “For me, there are two things that investment in technology can do: It can reduce the labour needed and it can allow us to be better informed as to when and how we target the labour we have.

“Secondly, the agricultural industry is quite a time consuming world – you have to be totally committed to your farm or business, but by bringing technology to the table, I think it would attract more young entrants into the sector and could provide young people with a better work-life balance.”

New project to investigate potato dormancy and sprouting

With CIPC under scrutiny, a new Horticulture and Potato Initiative (HAPI) funded project seeks to find new ways of controlling dormancy and sprouting in potatoes.

The project will identify key genes and regulatory mechanisms which underpin dormancy and sprouting behaviours in both potatoes and onions, with the aim of developing new storage strategies and varieties.

Dr Carmen Alamar, academic fellow at Cranfield University, said: “There are five million tonnes of potatoes produced in the UK per year which rely on long-term storage. Dormancy and early sprouting can have a huge effect on the marketability and the quality of stored potatoes.

“While the sprout suppressant, CIPC, is currently an option, as of July this year new legislation has meant it has to be applied at lower dose rates and using active recirculation, which is a concern for the industry.

“There are other chemical options which are available to us, but many of them increase the sugar levels within the potato, causing it to brown during frying. Therefore, it is crucial the industry comes together to try and find an alternative solution.”

Understanding nitrogen key to higher yields

While nitrogen will always be the driver of potato production, relying solely on conventional sources supplied via the soil results in weak vegetative growth, according to David Marks, of Levity Crop Science.

He said: “When we feed crops N, they mostly take it up as nitrate, which means plants mostly use their N to put on top growth. In crops like potato, farmers must manage conflict between applying the N their crop needs, and the crop’s natural propensity to use that N to grow foliage rather than tubers. This leads to a reduction in tuber setting and bulking.”

To combat this problem, Levity Crop Science has developed Lono for Potato, a foliar-applied product which exposes the crop to bursts of amine N, which helps to direct growth towards tuber development.

To ensure the size and number of tubers are optimised, Dr Marks suggested one application at tuber initiation and a further three applications during bulking, using rates of about five litres/hectare.

Independent trials, which took place across Europe last year, showed use of this approach resulted in a yield increase of about 10 per cent, which equated to an extra four tonnes/ha (1.6t/acre) of potatoes on average. However in France, the associated yield increase was up to 30 per cent.

Dr Marks said: “The full programme would cost the farmer about £70/ha and the average yield increase has typically resulted in an extra £800 worth of potatoes, so to me it is a no-brainer.”