PCN control, now and in the future

Matthew BackHarper Adams University, Newport, Shropshire TF10 8NB

AHDB Winter Forum – East: 19th January 2016

Background

Pesticides are under threat…Authorisation directive 91/414/EEC replaced by EC 1107/2009

UK agriculture’s Gross Value Added (GVA) could fall by c. £1.6bn per annum if key agrochemicals are revoked(Andersons, 2014)

Potato cyst nematodes:

A2 quarantine pest for EPPO

Persistent: Encysted eggs can persist for 20+ years

Widespread: 64% of England & Wales/26% wareland in Scotland

Economically damaging: Up to 80% yield loss/GB cost c. £26M per annum

Background(continued)

AHDB – PCN Management GuideSue Hockland - Matthew Back - Vivian Blok - Ivan Grove - John Jones - Adrian Roberts – Jon Pickup

The provision of content document will cover recent developments in our understanding of: -

• length of rotation• cultivars and evidence of effect on yield• varietal resistance and tolerance• influence of chemical treatments and their incorporation• novel treatments such as biofumigation and trap cropping

Summary of PCN management

Seed grower

Following PCN

directive(2007/33/EC)

Ware grower

0.5% of land surveyed under directive(2007/

33/EC)

Determine species present

Cultivar selection1. Resistance

(target PCN species)

2. Tolerance (preserving yield)

1. Short term management -nematicide treatment

2. Long term management -rotation, biofumigation

3. High populations may benefit from soil fumigants

PCN ?

Continue to monitor & ensure

good hygiene

No

Yes

Voluntary sampling of

PCN

Globoderapallida

Globoderarostochiensis

1 1

2

3

8

4 5

678

Globoderarostochiensis

Ro1 Ro2 Ro3 Ro4 Ro5

Globoderapallida

Pa 1 Pa2/3

Cultivar choice: considerations

Eves-Van den Akker et al., 2015

‘Pathoscapes’ basedon sampling 15x 10 m areas in a singlefield

Based on sequencingmitochondrial DNA (cyt B)

Resistant/Low tolerance

Resistant/High tolerance

Susceptible/Low tolerance

Susceptible/High tolerance

Cultivar choice: considerations

The resistance status of the top ten ware potato varieties grown in Great Britain in 2015 (adapted from Swales, 2015)

Potato Variety GB planted area (ha) Resistance status against G. pallida Pa2/3,1 (rating)

Resistance status against G. rostochiensis(Ro1)(rating)

Maris Piper 17,137 Susceptible (2) Resistant (9)

Markies 6,426 Susceptible (2) Resistant (9)

Maris Peer 4,805 Susceptible (2) Susceptible (2)

Lady Rosetta 3,854 Susceptible (2) Resistant (9)

Melody 3,623 Susceptible (2) Resistant (9)

Estima 3,262 Susceptible (2) Susceptible (2)

Hermes 2,895 Susceptible (2) Susceptible (2)

Pentland Dell 2,716 Susceptible (2) Susceptible (2)

Marfona 2,379 Susceptible (2) Susceptible (2)

Harmony 2,313 Partially resistant (4) Partially resistant (4)

Potato Variety

Resistance status against G. pallida Pa2/3,1 (rating)

Resistance status against G. rostochiensis(Ro1)(rating)

End market

Arsenal 8-9 8-9 Fries/chips

Crisps4all 6 9 Crisping

Eurostar 8-9 8-9 Fries/chips

Harmony 4 4 Ware (pre-pack/bakers)

Innovator 8-9 (not resistant) Fries/chips

Panther 8 3 Ware

Performa 8-9 4-6? (partially reistant) Fries/chips

Maritiema 5 8 Ware/friesRamos 4 8 Fries/chips

Vales Everest 6 4 Processing (chips)

Commercially available potato varieties with resistance to G. pallida

Nematicide options[Oximecarbamate - Vydate 10G® (10% oxamyl) – Not available in 2016]

Organophosphates • Nemathorin 10G® (10% fosthiazate) (Note: harvest interval 17+ weeks after

application)• [Mocap 15G® (15% ethoprophos) 40 kg/ha – for a reduction only – main

application is for wireworm]

MITC precursors• Metam sodium 510 (510 g/l metam sodium) - reduced rate of use now 300

L/ha - restricted to 1 in 3 years on same land• Basimid (97% w/w dazomet)

Garlic based product - NEMguard DE – Potatoes are not on the 2016 label

Nematicide Stewardship Programme

• Joint industry approach • Set minimum stewardship standards for application of all nematicides• Core values

• Protect the environment• Protect the consumer• Protect the operator

• Incorporated into the Red Tractor Assurance Scheme• To be incorporated within the Voluntary initiative Programme• Three season time frame for industry adoption

Key elements of nematicidestewardship

Operator requirements

Machinerycalibration

maintenancerecords

Protecting the environment – preventing granule spills

Operator exposure

Post application

– wildlife monitoring

Rotational decline of a `high` PCN population density   

   Year                 Annual decline rate (%)    

   

 10  

 15  20  25 

 30 

 35 

 40             

Population density  category        

 0 

 100 

 100  100  100 

 100 

 100 

 100 

                `HIGH` 

 1 

  90 

  85   80   75 

  70 

  65 

  60 

  

 2 

  81 

  72   64  56 

 49 

  42 

  36 

  

 3 

  73 

  61   51   42 

 34 

  27 

  22 

              `MEDIUM` 

 4 

  66 

  52   41   32 

 24 

  18 

  13 

  

 5 

  59 

  44   33   24 

 17 

  12 

  8 

  

 6 

  53 

  38   26   18 

  12 

   9 

   5 

  

 7 

  48 

  32   21   13 

   8 

   8 

   3 

                 `LOW` 

 8 

  43 

  27   17   10 

   6 

   5 

   2 

  

 9 

  39 

  23   13    8 

   4 

   3 

   1 

  

 10 

  35 

  20   11    6 

   3 

   2 

   1 

  

0

5

10

15

20

25

30

35

1 2 3 4 5 6 7 8 9 10 11-20

20+%

of f

arm

s

Rotation length (years)

Minnis et al. (2002)

Biofumigation

The performance of biofumigant cover crops is variable….Many growers are scepticalCommercially available cultivars lack supporting data

Source: Alec Roberts & Bruno Ngalahttp://www.youtube.com/watch?v=Ca-PC-4LkIY

Solanum sysymbriifolium/trap cropping

• Available in UK as DeCyst and Foil-sis

• Stimulate hatching but PCN do not develop cysts

• Typically grown from May to October

Other management considerations

• Hygiene: soil movement, management of volunteer potatoes

• Biological control – no commercially available products available yet

• Novel methods

Update on AHDB projects on PCN

1. 114R476 - Effectiveness of Biofumigant Crops for the Management of PCN in GB

2. PhD Studentship - Characterisation of Potato Cyst Nematode Populations (PCN) in Great Britain for Sustainable Crop Management

3. Provision of Content for a Best Practice Guide for the Management of PCN

New AHDB PhD studentship on root lesion nematodes

• Molecular assays for root lesion nematode species (JHI/HAU)

• Determine the distribution of Pratylenchus spp in potato growing land

• Determine potato damage thresholds for Pratylenchusspecies

• Conduct field based studies to assess the performance of damage thresholds

• Determine whether a relationship exists between Pratylenchus species and Rhizoctonia solani

R&D - next steps

• More data on tolerance• Greater Globodera pallida resistance for pre-pack/better

uptake of these cultivars• Development of the PCN model• Biofumigation – still questions unanswered• Novel cover crop species

AcknowledgementsAHDB – Potatoes

Sebastian Eves Van den-Akker (University of Dundee)

Neil Beadle (DuPont)

Alan Horgan (Certis)

PhD ‘biofumigation’ projects at HAU• William Watts – funded by Frontier Agriculture Ltd.• Bruno Ngala – funded by Harper Adams University, Agrovista Ltd. and

Barworth Agricture Ltd.