Thursday 5 March 2020 - Microsoft...water treatment for a wide range of predominantly UK nurseries...

Basil Downy Mildew Workshop

Thursday 5 March 2020

Stockbridge Technology Centre, Cawood, Selby YO8 3TZ

Basil Downy Mildew Workshop Stockbridge Technology Centre, Cawood, Selby YO8 3TZ

5 March 2020

This workshop will highlight Basil Downy Mildew (BDM) disease sources, its spread, growth and development within a crop and new information to aid with its management.

Programme

10:00 – 10:30

10:30 – 10:55

10:55 – 11:25

11:20 – 11:45

11:45 – 12:10

12:10 – 12:25

12:25 – 13:30

13:30 – 14:15

14:15 – 14:45

14:45

Registration

Basil Downy Mildew: Management options and challenges Simon Budge, Vitacress Herbs

Cultural control of downy mildews in protected cropping Andrew Beacham, Harper Adams University

Risk factors for downy mildew and potential for use of decision support Tim Pettitt, Eden Project Learning

Seed-borne inoculum for basil downy mildew: detection, incidence and transmission Tom Wood, NIAB

Plant Protection Products for BDM control Bolette Palle-Neve, AHDB

Lunch

Breeding for BDM resistance & Seed treatments for BDM control Guillaume Fremondiere (Iteipmai, France)

Tour of STC vertical growing room and the UV-C robot that is being used in trials to control basil downy mildewroom

Event end

Speaker biographies

Simon Budge, Vitacress Herbs Solutions Ltd

Simon started working at the Glasshouse Crops Research Institute in West Sussex straight from school in 1979 as an Assistant Scientific Officer. After accumulating several years’ experience he became specialised in the biological control of plant diseases and progressed to a more senior role. GCRI became part of Horticulture Research International and following the site’s closure, Simon was relocated the Wellesbourne site in 1996 to continue plant pathology research.

After 20 years’ service, a life-style change saw a move to Norfolk where Simon became Microbiologist at Bernard Matthews. This was a very big

contrast in work environment but one that would prove very useful for a return to research in horticulture but in a commercial setting.

Simon started working at Vitacress (what was then Humber VHB) in 2006. After initially taking on a R&D support role, as Agronomist, he is now responsible for all R&D management, crop protection, growing issues and product quality.

Dr Andrew Beacham, Harper Adams University

Dr Andrew Beacham is a Lecturer in Sustainable Crop Production and Agronomy at Harper Adams University, Shropshire, UK. His research specialises in stress in protected horticultural crops, molecular plant pathology, postharvest quality and whole plant physiology. He has previously carried out and reported AHDB-funded research in protected herb crops (PE 015 “Inducing compact growth and improved shelf life in herbs by mimicking drought signals”). He has authored a number of publications regarding protected horticulture production including a manuscript regarding pest and disease management in vertical farms which highlights the importance of temperature and humidity and

potential of lighting changes such as UV deployment for disease control. Andrew has a PhD in plant pathology and was involved with a BBSRC HAPI project on lettuce fungal pathogens among other studies.

Thomas Wood, NIAM

Thomas Wood is research group leader at NIAB in Cambridge specialising in genetics, genomics and pathology of horticultural and arable crops. His group’s work focuses on a wide range of crop pathogens with an over-arching goal of minimising the effects of disease on yield and quality. Positioned at the interface between host and pathogen, efforts in the lab aim to understand how variation in pathogen diversity and host resistance affect productivity in agricultural and horticultural production systems, particularly diseases caused by fungal and oomycete pathogens. Current research is focussed towards developing enhanced pathogen diagnostics

using conventional PCR, isothermal and sequencing based approaches to improve knowledge of pathogen population structure both here in the UK and overseas.

Speaker biographies Cont’d…

The practical application of this work is essential for the delivery of improved diagnostics strategies to support the growing community to help reduce disease incidence and severity through pre-emptive testing, and for

enabling early detection to aid effective disease management. Tom has worked with basil downy mildew in a number of collaborative research projects including AHDB project PE024 - Basil: Improving knowledge and control of downy mildew in protected and outdoor crops where he managed a series of outdoor production trials, EU Horizon2020 Emphasis: Effective Management of Pest and Harmful Alien Species designing pathogen-specific isothermal diagnostics, and the current AHDB Aerial oomycetes project CP184 where he is overseeing the development of strategies for quantifying the level of viable pathogens in seed.

Tim Pettitt, Eden Project Learning

Tim has recently returned to Eden as a member of Eden Project Learning, to lecture on their degree and post graduate program and carry out horticultural research. He was a member of the University of Worcester’s plant pathology research group for five years ago, after working as plant pathologist and Science Team manager at Eden Project in Cornwall, prior to this he worked at HRI Wellesbourne and Efford as a research leader specialising in soil and water-borne diseases (especially oomycetes). Tim has 30 years’ experience {on both the ‘commercial’ and ‘research provider’ sides of the fence}, working on epidemiology,

monitoring and especially management and control of soil- and water-borne diseases on a wide range of host plants from most sectors of UK horticulture as well as tropical commodity crops. Over the last 25 or so years, Tim has carried out regular water testing and consultancy relating to water treatment for a wide range of predominantly UK nurseries and is currently working for several nurseries on detection of oomycete pathogens, especially Phytophthora and Pythium species, using conventional plating methods and lateral flow device (LFD) kits deploying newly-raised antibodies developed in AHDB project CP136. He is also working on the new AHDB Aerial Oomycetes project CP 184. And has just finished work collaborating (mostly visiting nurseries and carrying out on-site sampling) on a large tree health initiative project using next generation sequencing to identify the range of Phytophthora species present on tree and hardy nursery-stock nurseries.

Bolette Palle-Neve, AHDB

Bolette is part of the Crop Health & IPM Team and manages the Extensions of Use Programme. Her specific area of responsibility is the leafy salads sector, fresh herbs, alliums, brassicas and root crops. A key part of Bolette’s work is to liaise with the industry, manufacturers of plant protection products, the Chemicals Regulation Directorate (CRD) and a range of commodity groups across Europe and elsewhere to gather the information and safety data required for suitable candidate plant protection products. As well as pursuing approvals for new products that have performed well in AHDB-funded trials, Bolette also works with Panel members and growers to identify gaps in the crop protection armoury.

Guillaume Fremondiere, Iteipmai,

Head of the south east experimental station of the iteipmai Head of the characterization and valorization of the genetic resources of the iteipmai

MAP breeding and variety evaluation including genotyping and phenotyping Agronomical experimentation on MAP Crop Management on MAP Domestication of wild species of MAP Intellectual property on vegetal species Through my company (iteipmai) : phytochemistry and bibliographic resources

Basil Downy Mildew Workshop Stockbridge Technology Centre, Cawood, Selby YO8 3TZ

5 March 2020

Contents

Title Speaker Page

Basil Downy Mildew: Management options and challenges

Simon Budge, Vitacress Herbs

1

Cultural control of downy mildews in protected cropping

Andrew Beacham, Harper Adams University

6

Risk factors for downy mildew and potential for use of decision support

Tim Pettitt, Eden Project Learning

12

Seed-borne inoculum for basil downy mildew: detection, incidence and transmission

Tom Wood, NIAB

16

Plant Protection Products for BDM control Bolette Palle-Neve, AHDB 25

Breeding for BDM resistance & Seed treatments for BDM control

Guillaume Fremondiere (Iteipmai, France)

29

Basil Downy Mildew: Management options and challengesSimon Budge, Vitacress Herbs

Basil Downy Mildew:Management options & challenges

Simon BudgeVitacress Herbs

Disease history at Vitacress

First Downy Mildew outbreak: 19 August 2010

8 days later: symptoms seen in 80% of mature standard basil and globe basil crop

Confirmed by FERA as Peronospora belbahrii and a Plant Health Notice imposed

Plant Health visit threatened destruction of whole basil crop


• QA had noted what they thought was a nutritionalissue on the odd pot 6 days previously

Page 1



• Fungicides approved for use on protected basil and recommended for activity against Downy Mildew:

• Aliette 80 WG: (Fosetyl-aluminium) max 1 x application per crop 14 day harvest interval

• Amistar: (Azoxystrobin) 14 days harvest interval May to October (21 days November to April)

• Previcur Energy: (Fosetyl-aluminium + propamocarb hydrochloride) 21 day harvest interval

• Proplant: (Propamocarb hydrochloride) 14 day harvest interval

• SL 567A: (Metalaxyl-M) max 2 x applications per crop 14 days



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Downy Mildew Outbreaks

201020132014201620172019

Page 3


Current control measures

• Environmental control:o Time of irrigation – crop and bench dry going into

the eveningo Relatively aggressive heat/vent regime to keep crop

dryo Night break lighting – ensure no more than max 4

hours continuous darknesso ‘Night break’ humidity – a one-hour aggressive

heat/vent period in the middle of night


• Cultural:o Seed source: split summer/autumn productiono Seed testing: in-house using ‘box test’o Seed heat treatment: scrutiny of processo Spacingo Growing media/nutritiono Resistant varieties?o Daily crop walking and rogueing


• Plant Protection Productso Available effective chemical pesticides now severely

restricted: only Azoxystrobin and Mandipropamido Trials using Fytosaveo Karma ?o Amylo X ?

Page 4


Further work

• In what form is the Peronospora in/on the seedwhen no oospores have been found and conidiaare clearly quite fragile?

• How does the disease progress from seed tofirst disease expression?

• What are the conditions that influence thatprogress: biotic and/or abiotic?

• Why does it virtually always first show at thesame plant growth stage?

Further work

Thank you

and good luck!

Page 5


Cultural Control of Basil Downy Mildew Using Lighting Treatments

Andrew M BeachamHarper Adams University, Shropshire, UK

Lighting for Control of Basil Downy Mildew

• Overview of progress to date

• New AHDB-funded review

Basil Downy Mildew and Light

• Peronospora belbahrii requires at least7.5 h dark period with high humidity tosporulate - exposure to light can suppress conidia (asexual spore) formation

• Infection itself may also require a dark period cf. Pythium violae

• Night break lighting as a possible solution?

JIC

Page 6

Night Break Lighting

Lopez‐Lopez et al., 2014

• 14 h light, 10 h darkness gave full sporulation(positive control)

• Treatments in which the 10 h darkness periodwas interrupted with light showed reduced sporulation

• Either 4 h light in middle of dark period or alternating 2 h periods of light and dark

• 24 h of light showed no sporulation at all (negative control)

Night Break Lighting

AHDB PE 024• Investigation of night time illumination• 0 to 8 hrs treatment with

incandescent lighting• Plants exposed to 4 hrs of light had

lowest disease severity, plants notilluminated at night had the highest disease severity

• However the differences were notstatistically significant Jennings et al.,

2017

Side Effects?

• 24 h of light provision can lead to no sporulationat all in some studies (Lopez‐Lopez et al., 2014)

• However, continuous light has also been found to reduce the latent phase of infection to just 5 days (Cohen et al., 2017)

• Sporophores (fruiting body structures) can still emerge from stomata under light (Cohen et al., 2013)

(Left) Sporulation developing in the dark and (right) sporophoreformation under cool white

fluorescent light (Cohen et al., (2017) Phytopathol. 107: 1149-

1160).


Page 7


• Light responses of P. belbahrii may involve a red light photoreceptor (unlike other similar organisms)

• Blue light controls stomatal opening

• Use of red or blue LED light as another possible control route (e.g. as night break lighting)?

Red and Blue Light

Patel et al., 2016; Radetsky et al., 2020

• Night time LED treatment applied during sporulation

• BDM suppression depends on dose of visible spectrum light

• Dose is a combination of wavelength, amount, duration and application time Jaimin Patel,

LRC

Red and Blue Light

• Duration of lighting necessary will depend on day length (shorter day, longer lighting period necessary)

• Both red and blue light (PPFD approx. 60 μmol m-2s-1) reduces BDM sporulation >99% when applied continuously at night

• Red and blue light equally effective

• At lower doses, efficacy is lower and better for continuousvs intermittent application

• Treatments can increase leaf number and size (and greenness?)

Jaimin Patel, LRC


Page 8

Red and Blue Light

• Red light may increase the efficacy of fungicidalproducts such as Actigard(acibenzolar-S-methyl) andOrganocide (sesame oil)

• Prophyt (potassium phosphite) most effective regardless of lighting regime

Patel et al., (2016) J Phytopathol 164: 1022-1029.

Red and Blue LightHowever:

• The inhibitory effect of light does not pass to the shaded parts of the same leaf and requires a minimum temperature of 15°C (Cohen et al., 2013).

• Red light leads to stretching

• No details on sporophore production

• Red light reduction of BDM found in other studies (Cohen et al., 2013). Mixed results regarding the efficacy of blue light in BDM suppression

Jaimin Patel, LRC


• Ultraviolet (UV) radiation has been found to induce downy mildew resistance in lettuce and reduce sporulation of Bremialactucae

• Unlike in the case of red light, UV may partly act as a priming agent for the hostplant defence system

• However some studies find a reduction ofUV to be beneficial (e.g. in cucumber)

• Use of UV (e.g. as a pre-inoculation ‘priming’ treatment) to control basil downy mildew?


Page 9

Ultraviolet Light

• Pre-inoculation treatment of plants with UV-B radiation has been shown to induce resistance to P. belbahrii (Patel et al., 2017).

• No significant effect on fresh or dry weight

Side Effects?

• Dou et al. (2019) – UV-B increased leaf content of antioxidants such as phenolic compounds, flavonoids and anthocyanins

• However, UV-B can reduce basil yield and appearance depending on dose

• Lower UV-B doses are required to avoid stress damage (Mosadegh et al., 2019)

Dou et al., 2019 Agronomy 9(8): 434

UV-B dose (hours, days)

New AHDB Review

• As part of a new AHDB-funded downy mildew project we will be conducting a review of existing literature for cultural control of downy mildews:

• Lighting, temperature, humidity, ventilation and heat

• Range of downy mildew diseases in a number of protected horticulture crops

• Aim to identify knowledge gaps and generate recommendations for cultural control measures and/or future research priorities


Page 10

Considerations for Recommendations

• Efficacy• Need to combine with other approaches?

• Format – e.g. LED/UV lamps/film covering

• Feasibility for use in protected horticultural systems• Cost-effectiveness• Installation• Operation

• Potential negative consequences

Acknowledgements

• Katy James• Jim Monaghan • Nicky Randall

• Cathryn Lambourne• Kim Parker

• This work forms part of a larger research project with Cornwall College, the James Hutton Institute and a number of industryrepresentatives

• Tim Pettitt

• Alison Lees

References

• Dou, H., Niu, G., Gu, M. (2019) Agronomy 9(8): 434.

• Cohen, Y., Vaknin, M., Ben Naim, Y., Rubin, A.E. (2013). PLoS ONE: 8: e81282.

• Cohen, Y., Ben Naim, Y., Falach, L., Rubin, A.E. (2017). Phytopathology 107(10): 1149-1160.

• Jennings, P. (2017). AHDB PE 024 Final Report.

• Lopez-Lopez, A., Koller, M., Herb, C., Scharer, H.J. (2014). II International Symposium on Organic Greenhouse Horticulture 1041: 213-219.

• Mosadegh, H., Trivellini, A., Lucchesini, M., Ferrante, A., Maggini, R., Vernieri, P., MensualiSodi, A. (2019) Plants 8(10): 396.

• Patel, J.S., Zhang, S., McGrath, M.T. (2016) J Phytopathol 164(11-12): 1022-1029.

• Patel, J.S., Radetsky, L., Plummer, T., Bierman, A., Gadoury, D., Rea, M.S. (2017). APS Annual Meeting 2017 (Poster).

• Radetsky. L/. Patel, J.S., Rea, M.S. (2020) HortScience doi.org/10.21273/HORTSCI14822‐19


Page 11


Risk factors for downy mildew and potential for use of decision support

Tim Pettitt

Early signs of disease

Cohen et al. (2017). Phytopathology 107: 1149‐1160.

Sporulation

Starts 5‐10 days after infection

Page 12

• Sporulation Dark ≥ 7.5h RH >95% 5‐28oC opt 20oC

• Infection ≥4h LWD 10‐26oC opt 18oC

• Latent period 5‐10 days

• Effect of short ‘spore cloud’ exposure indicates entire process from sporulation to infection can happen in one‘risk period’ = similar to Bremia in lettuce and P.destructor in onion

Decision Support Systems/Tools DSS/DST

Jennings, P, Thorp, G, Townsend, J, Wood, T. (2017). Basil:

Improving knowledge and control of downy mildew in protected

and outdoor crops. AHDB Final Report project PE 024.

Stoneleigh, Agriculture & Horticulture Development Board,

41pp.


Page 13

Cohen & Ben‐Naim (2016) PLoS ONE 11(5): e0155330.

doi:10.1371/journal.pone.0155330

Interrupted night time wet periods

Forecasts/ModelsAvailability, Usefulness and Platforms?

Established system – great for well‐researched, well‐resourced systems like P.i. and (hopefully) Bremia

What about less well researched/resourced systems?

Disease Control


Page 14

30 MHz ‐ Impressions

• A software service – lots of data storage• Available anywhere data can be

accessed (PC Laptop Phone)• Info can be shared easily • Flexible/adaptable and wide range of

sensors

Summary

• Simple possibilities / ‘risk rules’

• Use of short heat/vents

• Forecast models adapted?

• Measuring what’s happening at the leaf level to guide action (e.g. 30 MHz)

[email protected]


Page 15

Seed‐borne inoculum for basil downy mildew: detection, incidence and transmission Tom Wood, NIAB

Seed‐borne inoculum for basil downy mildew: detection, incidence and transmission

AHDB Projects PE024 & CP184

Dr Thomas Wood

NIAB, Cambridge

Overview

• Basil DM

• Detection & diagnostics

• Disease transmission

• Incidence, attempting to interpret risk

Peronospora belbahrii (Pb)

Responsible for causing downy mildew on

‐ Sweet basil (Belbahrii et al., 2005)

‐ Agastache (Henricot et al., 2010)

‐ Coleus (Denton et al., 2015)

Other closely related DMs affect other members of the lamiaceae

Wikipedia/

www.gardenersworld.com

Page 16


Peronospora belbahrii (Pb)

• 8‐10 days development of symptoms under optimal conditions*

• Chlorosis

• Profuse sporulation on underside of leaves, less dense on top

• Dark grey coloration

• Conidia/spores bore from branched conidiophores

• Localized spread of disease

• Report of sexual oospores in leaf mesophyll from Israel (Cohen, 2013, 2017)

www.cabi.org

Detection & diagnosis

• Visually straight forward to diagnose…but then it is too late!

‐ Disease on a single plant can spread quickly

‐ Control often limited, issues with fungicide resistance


• Difficult to detect Pb using grow‐on tests

‐ Standard GR test using > 3 x 1000 seed

Sample Seed tested Symptomatic seedlings Infection (%)

3 3500 0 0

17 2500 0 0

19 3500 0 0

21 6000 0 0

AHDB PE024

Page 17



Molecular testing (DNA)

• PCR assays: Thines et al., 2009, Shao & Tian, 2015

• Isothermal assay: Caiazzo, unpublished (EU H2020 Emphasis project)

‐Specifically detect P. belbahrii, validated against databases, other spp.

‐ Extract DNA, test +/‐, quantification of DNA present

Detection and diagnosis

• qPCR – Detects all Basil DM present, compares quantity in samples versusstandard to estimate DNA content

Viability testing methods (CP184)

• Distinguish between live and dead cells

‐ RTPCR strategy (RNA, gene expression)

‐ Spores treated with PropidiumMonoazide

‐Illumination activates selective dye (>15 mins)

‐Binds to DNA of damage cells, delaying PCR

How much viable pathogen present and what risk does it pose?

Detection and diagnosis

Page 18


Live Dead

Transmission

New disease outbreaks…

• Local transmission from symptomatic plants

• Seed‐borne spread

• Potential for oospores on seed, debris?

Transmission

Optimal conditions for disease development…

• Most severe when plants kept wet for period exceeding 6 hours (Garibaldi et al., 2007)

• Highest levels of disease @ 20°C, no infection below 12°C/above 27°C.

• 8 to 10 days development , other DM Infections related to temperature, additive

• PE 024: infection between 5 ‐ 25°C, optimum temperature 15 ‐ 25°C.

• High humidity and prolonged moisture on the leaf surface (greater than 4 hours) was alsorequired for infection

• Direct penetration of host cells with appressorium‐like structure(Zhang et al., 2019)

Page 19


Zhang et al., 2019

Transmission

Establishing seed borne (internal) transmission

PE024: seed‐washing of contaminated lots

• Agitation, wetter, centrifugation

• PCR testing of washes (3 x 100 seed)

• 8 samples tested, all negative for external contamination

• Extraction from washed lots, all positive

‐ Levels of DNA present usually quite low

‐ Only a few seeds in a lot may be contaminated?

‐ Low level of pathogen = high risk

AHDB PE024

Transmission

• Home‐saved seed from trials testing strongly positive for pathogen

‐ 33 cycles in commercial lots versus 19 cycles – 3.3 cycles equivalent to 10 x more DNA, thus >10,000 times more DNA

‐No visible oospores (leaves/on seed coat – inside testa?)

‐Mycelial fragments?

‐Growth from mother‐plant into seed?

Require techniques for visualizing contamination

Page 20


Transmission

Oospores as a possible source of disease?

• Oopores associated with seed‐borne transmission in other DMs

• P. effusa – Oospores found in leaf tissue, on seed and inside seed coat

• Only reported cases in Israel for Pb

• Not observed in various indoor/outdoor experiments NIAB, FERA or UoTorino (5‐6 different isolates) , or elsewhere in the literature

Transmission

Visualizing contamination in seed

• Genetic transformation of Pb w/reporter proteins, confocal microscopy (time, costly)

‐ CP184: Classical staining and microscopy – trypan blue selectively stains dead fungal/oomycete tissues, leaving live tissue clear

‐ Sectioning and staining of infected seed, verify presence of viable spores

However, incidence likely to be low, thus lots of seed would need to be processed (3 x 1000)

Incidence

Investigating disease incidence in seed lots

• Potentially low levels can cause disease (0.02%, Garbaldi et al., 2004)

• How infested are seed lots, what risk do different levels of contamination pose?

• Viability of pathogen found in seed, distribution through lots?

Page 21


Incidence

• Small seed; TSW ~1.5 g

• Low levels of contamination = high incidence

• Requires an effective sampling procedure

• Possible to identify Pb in large bulks, 3 x100 establish standard (PE024)

• Testing of individual seeds, smaller batches difficult at commercial scale

‐ Time/labor

‐ Low pathogen DNA content per seed

Incidence

• Grow‐on testing largely ineffective

• PE024 ‘Box’ testing method…

Seed sampleNumber of seed

tested

Symptomatic

seedlings

Mean severity

(0‐5)

Infection

(%)

13 750 0 0 0

26 750 0 0 0

17 775 3 1 0.4

19 750 0 0 0

21 775 10 1 1.3

NIAB trial 100 0 0 0

Lot 21(2018) 525 0 0 0

Gilardi, 2016, unpublished

Incidence

• Use PCR to detect DNA Viable DNA

• CP184 seed‐lot testing (qPCR, viability methods*)

‐ Distribution of DM, how much pathogen actually present in samples?

‐ Do treatments result in a reduction in DNA?

Seed lot (3 X 1000) 3 X (2 X 500) 3 X (10 X 100) 3 x (20 X 50) 3 x (100 x 10)

CP 1 Untreated * * * * *

CP 2 Treated * * * * *

CP 3 Untreated * * * * *

CP 4 Treated * * * * *

Page 22


Incidence

• What infection levels pose a risk to growers?

‐ How much viable DNA = how much disease?

‐ Correlating DNA content with grow‐on very difficult; how to quantify?

‐ Identify contaminated lots grown under commercial production environment, parallel seed testing

Summary

Detection & diagnosis• Pb causes serious reduction in quality of sweet basil• Range of diagnostic methods available to detect Pb• Trialing viability PCR strategies to improve understanding the risk posedTransmission • Water/wind spread, moist conditions, wide temperature range, optimum 18‐25°C • Indication that Pb is transmitted inside seed resulting in new infections – need to prove this• Pathogen present at relatively low levels in commercial lots – dilution with healthy seedsIncidence• Low levels can result in high levels of disease• Testing underway to understand how widely distributed pathogen are in samples, how much is

viable• Possible to correlate viable DNA content with levels of infection with disease incidence/severity?• Support testing to demonstrate remedial treatments effectively reduce contamination

AHDB‐ Kim Parker‐ Cathryn Lambourne

FERA‐ Dr Philip Jennings

NIAB‐ Simon McAdam‐ Dr Beatrice Corsi

Acknowledgements

Page 23


Sampling!

Any downy mildew on basil (spinach, sage, mint, chives/onions, parsley)?

Seed‐lots with suspected DM contamination?

Please send to:

Tom Wood, NIAB, 93 Weaver Road, Cambridge, CB3 0LE

[email protected]

Tel: 01223 342200

Page 24

Plant Protection Products for BDM control Bolette Palle‐Neve, AHDB

Plant Protection Products for BDMPlant Protection Products for BDM

Bolette Palle NeveAHDB Crop Protection Senior ScientistBolette Palle NeveAHDB Crop Protection Senior Scientist

Basil Downy Mildew workshop 5 March 2020Basil Downy Mildew workshop 5 March 2020

Content

• Introducing the EAMU team

• EAMU programme spend

• Emergency applications

• Downy mildew actives

• Summary of efficacy work

• How do we plug the gaps?

EAMU Team

Adam Doxford• asparagus

• sweetcorn

• legumes

• cucurbits

• soft fruit

• tree fruit

Joanna McTigue• risk register

• ornamental crops

• protected edibles

• mushrooms

Bolette Palle Neve• brassicas

• root crops

• alliums

• leafy salads

• herbs

• propagation

Page 25


EAMU Programme annual spend

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EAMUs Residue trials

2019 £240,000 £227,000

2018 £240,000 £227,000

2017 £210,000 £240,000

2016 £150,000 £83,000

2015 £115,000 £180,000

• Good relationships with other Member States

• Close collaboration with manufacturers

Emergency applications

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Article 53 Emergency applications

DM actives due for renewal in Europe

Active Products Expiry date

Dimethomorph Paraat, Invader 30 July 2020

Mancozeb Invader, Fubol Gold WG 31 January 2021

Metalaxyl-M Fubol Gold WG, Apron XL, SL 567A 30 June 2020

Prompamocarb Infinito, Previcur Energy 31 July 2020

Fosetyl Previcur Energy 30 April 2020

Page 26


PE 024 – outdoor results

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PE 024 – protected results

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SCEPTREplus - lettuce downy mildew

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AHDB9958

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Presidium AHDB9957

AHDB9956

Downy mildew severity

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How do we plug the gaps?

Product Crop situation Comments

TBC (oxathiapiprolin+?) Outdoor & protected 2 co-formulations included in PE 024

Infinito(fluopicolide/propamocarb-hydrochloride)

Protected New residue data being evaluated. MRLs to be set

Frutogard (potassium phosphanate)

Protected Outdoor residue data not yet available

Ranman Top (cyazofamid) Protected & outdoor? To be investigated?

AHDB9958 Outdoor Approval likely 2022. Included in SCEPTREplus lettuce trial

Version: 16:9/2017-11-30a

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www.ahdb.org.uk

‘Inspiring our farmers, growers and industry to succeed in a

rapidly changing world’

‘Inspiring our farmers, growers and industry to succeed in a

rapidly changing world’

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Breeding for BDM resistance & Seed treatments for BDM control Guillaume Fremondiere, Iteipmai, France

Basil (Ocimum basilicum) variety tolerant to downy midew (Personospora belbarhii)

the example of a breeding program

Basil Downy Mildew workshop – AHDB – 5th of March 2020


ContextEstimated turnover > 10M°€

250 ha of production in France + in door production

Markets : frozen herbs, fresh herbs, plants in pot

95% with Genovese style variety


Context

stomate

25 µm

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Strategies developped

in dooraboveground

open fields

in doorin soil

Basimil program


Tools developped for the breedingprogram

Con

trolle

dp

ollin

atio

nm

etho

d



620

30

40

50

60

70

80

90

100

ourc

enta

ge d

e pl

ante

ave

c sy

mpt

ôme

Cotylédon 1er étage foliaire 2e étage foliaire pointant 2e étage foliaire

Inoculation by spraying strain Pb2 (4.104oospores/mL) on variety MARIAN 4 stades phenological stage of contamination tested :

→ Susceptible stages

0

10

20

30

40

50

60

70

80

90

100

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

Pour

cent

age

de p

lant

e av

ec s

ympt

ôme

Jours après inoculation

Evolution of the % of symptoms according to the contaminated stage

Arti

ficia

lIno

cula

tion

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0

2

4

6

8

10

12

14

16

18

20

J+15 J+21 J+28 J+35

Inte

nsité

de

sym

ptôm

e

Intensity of symptoms on 18 different varieties

Basilia 3

N°22 Genovese

Basilia 2

Basilia 1

N°14

Marian

N°10

N°6

N°3

N°8

N°27

Eleonora

Medinette

N°12

Marseillais

N°7

N°9

Blue Spice

Inoculation by spraying strain Pb2 (4.104oospores/mL) on + 24 h in the dark

Arti

ficia

lIno

cula

tion



Collect of wil strains in France

No difference of agressiveness and virulence betweenstrains

0102030405060708090

100

Pb02 Pb07 Pb17 Pb18 Pb19 Pb20 Pb21 Pb22

Pour

cent

age

de s

ympt

ômes

Average agressiveness of each strain

02468

1012141618

Pb02 Pb07 Pb17 Pb18 Pb19 Pb20 Pb21 Pb22

Nom

bre

de v

arié

té s

ensib

le

Average virulence of each strain

Arti

ficia

lIno

cula

tion



Gen

otyp

ing

Literature on SSR/SNP markers developped on basilic

Identification of 277 SSR publiés

Amplification : 44 SSR (16%)

Development of 135 SSR

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Tissu

e cu

lture


Breeding program

Stabilization

Controlledcrossings

12 wildaccessions

Sanitarian screening

Genetic screening

Morphological screening

Organoleptic screening


Breeding program

Preb

reed

ing

(201

2 –

2013

-20

14)

Evaluation of 28 wildaccessions from CNPMAI

Polycross of the 12 best accessions

Evaluation of the progeniesin open fields

50 elites plants for F1 among the 12 families

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Breeding program

F1 (2

015)

1200 plantlets

Open field plantation

50 elites plants for BC1


Breeding program

BC1

(201

6)

3443 plantlets

804 tolerant plants

265 plants afteragronomical selection

(morpho, downy mildew, …)

50 elites plants for BC2


Breeding program

BC2

(201

7)

3125 plantlets

796 tolerant plants

286 genotypically similarto Marian

8 plants for Self crossingand vitroplants after taste

control

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Breeding program

AF1

(201

8)

877 plantlets

378 tolerant plants

282 plants with genovesestyle look

51 plants after participative taste selection = AF2


Breeding program

AF2

(201

9)

51 Self fertilized lines

Evaluation of each plants

Participative selection

8 lines selected= selection of the

8 corresponding « AF1 »

Multipication, plantation and polycross of the 8 elites for base

seeds production


Seeds production programAt each step : poycoss of the non discarded / non selected plants

> 2018 : base seeds « like » production

2019 : polycross of selected poarentsthanks to vitroplants = base seeds

2020 : « commercial » seedsproduction from base seeds

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Evaluation

Comparative evaluation 12 commercial varieties including : - Witnesses (Genovese, Marian, Eleonora)

- DM tolerant varieties (2D, Adi, Devotion, Gemini, Obsession, Passion, Prospera®, Thunderstruck)

- Base seeds « like » of the candidtate(POP6)

Criterias of evaluation : - Tolerance to downy mildew- Genovese style morphotype- Genovese style taste- Yield


Evaluation1st harvest : no significative differenceson yield ; no DM

modalite moy_ajust Dunnett_5pct

Tukey_5pct

POP6 11,68 ....b a.Thunderstruck 11,13 ....b ab

2D 10,55 ....b abProspera(r) 9,60 ....b ab

Devotion 9,28 ....b abPassion 9,08 ....b ab

Obsession 8,19 ....b abGemini 7,95 ....b .bMarian 5,95 a....

Eleonora 5,42 a....Adi 4,70 a....

Genovese (apron) 4,60 T.... 0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

Estim

ate

d to

ns/h

a

Compared yield on 2nd harvest

Good tolerancy, light symptoms

High Tolerancy, very few symptoms

Sensitive, many hard symptoms

Behavior to DM : 2 very disctinct group


EvaluationGenovese before 2nd harvest

Thunderstruck before 2nd harvest

Very different from Genovese look Curlier / embossed ; bigger leaves ; more arrowed leaves

Obsession, Passion and Devotion are between Genovese and Thuyderstruckbut considered OK

POP 6 (candidate) before 2nd harvest

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EvaluationTaste evaluation by a jury of basil professional (fresh leaves and frozenleaves) : still under analysis

VOC evaluation by an exctraction in ethyl acetate + GC MS


Evaluation

Genovesetype

Sweettype

« No eugenol »type

Témoin sensible plein champ Témoin sensible sous abri

Témoin tolérant

VOC evaluation by an exctraction in ethyl acetate + GC MS


Conclusion

Confirmation of the interest of the candidate variety

Confirmation of the interest for « commercial » seeds production

Demand for growers experimetnation by private partners of the project

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Thanks for your attention

Herbes de

Meaux

Technical partners

Private partners

Public fundings

Head of the project

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