Disease control, alternatives to peat and nutrition

Transcription

1 HDC Mushroom Technical Day Disease control, alternatives to peat and nutrition 18 th March 2015 Macdonald Alveston Manor Hotel, Clopton Bridge, Stratford upon Avon, CV37 7HP Part of this event is disseminating information the MushTV project which is funded from the European Union's Seventh Framework Programme managed by REA-Research Executive Agency FP7-SME Grant Agreement No MushTV

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3 Programme for the Day Time Subject Speaker Arrival, registration and coffee Welcome Katie Irgin, HDC Fungal diseases of mushrooms and their control, including Dry Bubble, Wet Bubble and Cobweb Disease. Helen Grogan, Teagasc Brown Cap Mushroom Virus: symptoms, Kerry Burton, East sources of infection, prevention, and Malling Research developments in diagnostic techniques Coffee break Behaviour of Trichoderma aggressivum in bulk Phase III compost and best practice for composters, transporters and growers. Helen Grogan, Teagasc Best practice in the use of chemical disinfectants to prevent the spread of mushroom diseases Lunch Effects of different types of nutrient supplements when applied to phase 3 composts Alternatives to peat in casing materials for mushroom production Demonstration trays will be available to look at during the event Further questions, any other business, tea and coffee before departure Johan Baars, Mushroom Research Group Kerry Burton, East Malling Research Ralph Noble, East Malling Research Part of this event is disseminating information the MushTV project which is funded from the European Union's Seventh Framework Programme managed by REA-Research Executive Agency FP7-SME Grant Agreement No MushTV

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5 This research is funded from the European Union's 1 MushTV: Solutions for the mushroom industry to emerging disease threats from Trichoderma and Mushroom Virus X Contract No.: FP7 SME Fungal diseases of mushrooms and their control Seventh Framework Programme managed by REA Research Executive Agency FP7 SME 2011 Grant Agreement No MushTV MushTV: EU setup MushTV is a research project involving scientists, composters and growers aimed at reducing disease threats by improving knowledge Involvement of 17 partners from Ireland, United Kingdom, Belgium, the Netherlands and Poland MushTV: Fungal diseases and their control Main fungal diseases of concern: Dry Bubble (Verticillium, new name: Lecanicillium) Wet Bubble (Mycogone) Cobweb (Dactylium, new name: Cladobotryum) Disease symptoms and recognition Understanding how fungal pathogen can be spread When disease present: how to treat and control Hygiene is the key method to prevent infection 1

6 2 Dry Bubble: symptoms and recognition Symptoms vary depending on time of infection: Development stage Pin Small mushroom Older mushrooms Fully formed mushrooms Symptom small bubbles of tissue split stipes, some malformations wart like growths on cap grey brown spots on cap Dry Bubble: disease spread and transmission Spores are sticky and easily attached to: Flies Dust People hands, clothing, footwear Many surfaces picking tools, floors, door handles, canteen areas Dry Bubble: disease spread and transmission Initial infection: contamination of casing and casing equipment by windblown dust, flies or people Later infections during crop: watering over undetected or untreated pieces of bubble Flies play a crucial role in continuous cycle of disease symptoms on the farm: Flies are attracted to the infected mushrooms They move freely between growing rooms and outside around the farm and will spread disease further 2

7 3 Dry Bubble: disease spread and transmission Once Dry Bubble disease is established on the farm Continuous supply of sticky spores Causing a continuous cycle of disease symptoms, if left untreated Dry Bubble: disease treatment Clearly mark all areas to be treated Do not remove pieces of Dry Bubble (risk of spreading spores!) Use damp strong tissue paper to cover diseased area beyond edge To avoid bubble regrowth nearby: check treated areas regularly Bubble symptoms over a wide area: difficult to treat Consider terminating the crop at end of current flush Do not water again if taken to another flush Control of flies Dealing with Dry Bubble disease: fly control is critical Free movement between growing rooms and outside around the farm Contamination of freshly filled and cased growing rooms Difficult to break the cycle of disease Reduction of fly populations is needed: Monitor populations Use of fly control products Keep rooms and doors well sealed 3

8 4 Wet Bubble: symptoms and recognition Similarity between symptoms Wet and Dry Bubble Main symptom: development of large undifferentiated/irregular masses of tissue Other symptoms: Severely malformed mushrooms with heavy swollen stipes, deformed caps Wart like growth and cap spotting Droplets of amber colored liquid Soft and rotten tissue Wet Bubble: disease spread and transmission Spores are not sticky and not spread by flies Natural source of infection: Wet Bubble spores in the soil Spores can survive in organic debris on farms: compost and casing debris can act as a reservoir Outbreaks usually associated with contamination of casing or water supply with spore laden soil, dust or debris Wet Bubble: disease spread and transmission Undetected/untreated pieces of bubble produce masses of spores and those will be spread further when watering crop Spores become mixed with casing and compost debris on floors Spores spread around the farm on footwear and are blown around the farm in the dust fraction Contaminated dust and debris can cause new infection 4

9 5 Wet Bubble: disease treatment Clearly mark all areas to be treated Individual pieces of Wet Bubble can be removed carefully using a disposable glove or plastic bag, invert it, close it securely and dispose of it safely Use damp strong tissue paper to cover diseased area beyond edge To avoid bubble regrowth nearby: check treated areas regularly Bubble symptoms over a wide area: difficult to treat Consider terminating the crop at end of current flush Do not water again if taken to another flush Cobweb: symptoms and recognition Primary symptom: circular patches of cottony white cobweb like mycelium growing over casing soil Infected mushrooms can turn brown Cobweb spores landing on developing mushrooms cause brown irregular spotting symptoms Well developed mycelium develops a powdery and granular surface (massive sporulation) Older Cobweb colonies may develop pinky reddish tinge Cobweb: disease spread and transmission Rapid extension of small Cobweb patch: at least 1 2cm/day Favoured development by high relative humidity Production of masses of dry powdery spores Airborne spores easily dislodged by physical disturbance 5

10 6 Cobweb: disease spread and transmission Undetected/untreated Cobweb patch releases masses of spores when watered Rapid distribution of airborne spores around growing room via air circulation Airborne spores exit growing rooms into dust and debris around the farm Infection of new crops via contaminated equipment or casing, or via unfiltered air currents entering growing rooms Cobweb: disease treatment Clearly mark all areas to be treated Use damp strong tissue paper to cover Cobweb patches beyond edge Ensure well sealed edges to prevent dry spores escaping into the air To avoid regrowth nearby: check treated areas regularly Chemical and biological control of diseases Declining availability of approved plant protection products for use on mushrooms Prochloraz use of a single product can result in development of resistant pathogen populations Use will not be effective if secondary infections are allowed to develop Important to identify and treat areas of disease 6

11 7 Chemical and biological control MushTV: evaluation of several new biocontrol and chemical products Compared to Sporgon: little or no control against main diseases One product is promising ongoing trials in progress Good control of Dry, Wet Bubble and Cobweb by Sporgon Control of Cobweb No. of Cobweb patches No treatment Product A Product B Product C Sporgon 3g/m² 3rd flush 2nd flush 1st flush Sporgon 1g/m² General disease prevention and control measures Protect casing soil and casing operations from contamination By spore laden water splash, dust and debris Personnel must wear clean overalls, disposable gloves and boots Ensure protection from dust and flies during storage Primary source of contamination: machinery, personnel, dust and flies so just before use thoroughly wash and disinfect all casing equipment General disease prevention and control measures Prevent early crop contamination After filling and casing: clean away debris on the floor Be aware of quality of walls/ceilings of growing rooms Coatings, door seals, vents and filters Keep doors and vents well sealed During case run: keep doors into growing rooms closed as much as possible 7

12 8 General disease prevention and control measures Monitor disease occurrence Inspect mushroom beds regularly for disease, especially prior to watering Train disease personnel to monitor, record and treat disease Harvesters should be encouraged to report diseases Check hygiene measures to ensure they are being implemented correctly General disease prevention and control measures Treat disease before watering To prevent development of secondary infections Watering over untreated disease is a major cause of disease spread Spore laden water splash onto mushrooms, beds, floors, shelving, picking trolleys contaminating footwear, clothing and harvester s hands For Cobweb, turn off air circulation before watering to minimise dispersion of airborne spores General disease prevention and control measures Limit contamination and spread Start of the day: clean clothes, clean and disinfected picking tools No transfer of picking equipment between growing rooms Use of alcohol hand gel on entry and exit of every growing room Use of disinfectant foot dips or mats at entrance of every room Good practice: start picking 1 st flush 2 nd flush 3 rd flush Clean and disinfect concrete areas and corridors outside growing rooms at the end of every day to kill off any spore loaded contaminated dust/debris Disinfect daily door handles, control panels and specific surfaces canteen area If disease level is very high: consider terminating crop early 8

13 9 General disease prevention and control measures End of crop routines Before emptying: steaming out the growing room ideally C compost temperature for a minimum of 8 hours After emptying: clean and disinfect thoroughly floors growing room, shelves and netting to remove debris Remove spent compost off site as soon as possible When steaming out is not possible: Spray off crop and floors with an approved disinfectant to give a surface kill After emptying: wash and disinfect floor, shelving, walls and nets General disease prevention and control measures Take home message: HYGIENE is the primary control measure Review hygiene procedures to ensure high level of hygiene and that they are implemented correctly If disease level is very high: consider terminating crop early Further information MushTV Factsheets: 01/15 Use of chemical disinfectants in mushroom production 02/15 Brown Cap Mushroom Virus (associated with Mushroom Virus X) prevention 03/15 Understanding Trichoderma aggressivum in bulk Phase 3 compost HDC factsheets and publications 09/08 Identification and control of Dry Bubble Disease of mushrooms 10/08 Identification and control of Cobweb Disease on mushrooms HDC grower summaries & reports: See HDC website ( for M6a, M13, M14a b c, M22, M26a, M30, M31, M33, M33a, M58 and CP4 9

14 10 Images kindly provided by Inagro, Teagasc, AFBI and Sylvan Thank you for your attention VOC 10

15 This research is funded from the European Union's 11 MushTV: Solutions for the mushroom industry to emerging disease threats from Trichoderma and Mushroom Virus X Contract No.: FP7 SME Brown Cap Mushroom Virus Seventh Framework Programme managed by REA Research Executive Agency FP7 SME 2011 Grant Agreement No MushTV MushTV: Brown Cap Mushroom Virus (BCMV) The European mushroom industry is highly successful producing more than 2 bn worth of mushrooms per year MushTV is a research project involving scientists, composters and growers aimed at reducing disease threats by improving knowledge MushTV: Brown Cap Mushroom Virus Increased scale of production & increased mechanisation Change by growers from receiving Phase 2 compost in blocks/bags to Phase 3 compost in bulk: shorter crop cycle = more crops per year 11

16 12 MushTV: Brown Cap Mushroom Virus The MushTV project aims to provide growers and composters with: A better understanding of the causative agent of Brown Cap Mushroom Disease An understand of how MVX/BCMV infects mushroom compost and how it is spread around the industry Improved diagnostics: early warning systems Information on the effectiveness of disinfectants & disinfection strategies against A. bisporus (as host for MVX/BCMV) Brown Cap Mushroom Virus: Background Outbreaks of Brown Cap Mushroom Disease caused by Brown Cap Mushroom Virus (BCMV) occur sporadically every year Outbreaks linked to breakdowns in hygiene procedures or lack of steam cook out Infection can occur at compost facilities, in transport or on growing facilities Shared responsibility of ALL in the industry to prevent likelihood of contamination Brown Cap Mushroom Disease: Symptoms The symptoms of Brown Cap Mushroom Disease include brown, cream or off white mushrooms Can occur as a few per shelf or up to the bulk of a flush A few browns on a shelf Shelf of off white poor quality mushrooms May manifest postharvest as browning or opening 12

17 13 Brown Cap Mushroom Disease: Symptoms The symptoms of Brown Cap Mushroom Disease show great variability in expression: A few brown mushrooms can mean that the crop and/ or compost is highly infected with the BCMV. This compost could be the source of further outbreaks and it is important to maintain high standards of hygiene, including steam cook out. Sources of infection Disease occurs as a result of contamination on facilities e.g. from equipment or debris Most vulnerable times for infection: tunnel emptying, during transport & at shelf filling Sources of infection Pilot studies identified best locations & samples for testing Phase 3 compost at tunnel emptying on compost facilities Mushrooms & compost during cropping on grower facilities Survey of compost and grower facilities: MVX/BCMV detected in 3% of compost from phase 3 facilities 16% of samples from grower facilities 13

18 14 Brown Cap Mushroom Disease: Biology Viruses of MVX complex have been sequenced and characterised: 19 viruses currently known which can be present in mushrooms Viruses previously identified: AbV1 MBV AbEV1 AbSV responsible for La France disease (also known as LIV) Mushroom Bacilliform Virus linked with other viral diseases including La France A. bisporus Endornavirus 1 previously associated with MVX complex A. bisporus Spherical Virus AbMV1 A. bisporus Mitovirus 1 New viruses identified in MushTV: AbV16 (BCMV) responsible for Brown Cap Mushroom disease AbV6 also associated with Brown Cap Mushroom disease Other viruses of unknown pathology: AbV2, AbV3, AbV5, AbV7, AbV8, AbV9, AbV10, AbV11, AbV12, AbV13, AbV14, AbV15 Brown Cap Mushroom Disease: Biology Mushroom viruses previously known & characterised: La France disease: Main symptom is yield loss Other related symptoms include distorted fruit bodies stipe elongation, tilted caps or small caps on normal size stalks; premature opening, discoloration & bare patches occasionally occur Mushroom Bacilliform Virus (MBV): Often present with other viruses including La France and MVX Link to symptoms not established possibly exacerbates symptoms of other viruses Brown Cap Mushroom Disease: Biology Newly sequenced and characterised viruses associated with brown symptoms: AbV16 or BCMV is largely responsible for Brown Cap Mushroom Disease AbV6 and MBV may also contribute to browning disease AbV16 can be present in a crop but symptoms go unnoticed High levels AbV16 correlate with occurrence of browning symptoms 14

19 15 Brown Cap Mushroom Disease: Epidemiology Trials to determine if tiny amounts of MVX infected material from facilities could cause brown symptoms to develop in crops from healthy compost Compost used as inoculum for first time in trials: industry sourced compost & debris as inoculum Linked samples of compost same compost at different stages in crop cycle Symptoms were measured using chromameter: Δe value: 10 = good quality white mushroom Brown Cap Mushroom Disease: Epidemiology Compost taken from 4 stages of crop: all positive for MVX Brown symptoms only in treatment 4: compost taken from under symptomatic mushrooms in an affected crop Brown Cap Mushroom Disease: Epidemiology Debris samples from compost & grower facilities used to infect healthy spawn run Phase 2 15

20 16 Brown Cap Mushroom Disease: Epidemiology Debris samples from compost & grower facilities used to infect healthy spawn run Phase 2 MVX status of samples unknown No obvious brown symptoms however resulting mushrooms from some treatments tested positive Monitoring & Detection Grower awareness of symptoms vital: Chromameter can measure colour If symptoms present adopt precautionary principle extra attention to hygiene Improved RNA extraction method (from compost) developed Highly sensitive molecular test developed for AbV16, AbV6 & MBV Virus levels correlated with disease severity Provide early warning system for the industry Prevention Hygiene is a key method to prevent infection Steam cook out essential! Disinfectants will NOT completely kill mycelium bound in compost Cleaning away compost fragments from machinery, nets and tunnels is critical Clean; disinfect; rinse is recommended 16

21 17 Recommendations: Growing facilities Steam cook out minimum C for 8hrs at end of every crop!! Thoroughly clean (remove all compost & debris), rinse & disinfect all equipment & machinery prior to & after use Concrete areas & corridors should be washed & disinfected at the end of every day Dispose of mushroom waste appropriately Filling of fresh Phase 3 should be done in isolation: other growing rooms should remain closed, no emptying or cleaning at same time Periodically test mushrooms & compost for virus presence Recommendations: Compost facilities Steam cook out or pasteurise tunnels between every batch of Phase 3 compost If possible, fill and empty Phase 3 tunnels at different ends dedicated equipment for each activity Highest levels of hygiene during spawning: complete isolation Remove compost debris & thoroughly clean, floors, winches, conveyors & all other equipment prior to use Periodically test Phase 3 compost for presence of virus Recommendations: Haulage contractors All equipment used in transport: vehicles, trailers, filling heads, hoppers Clean and disinfect inside & outside Between every location 17

22 18 Further information MushTV Factsheets: 22/14 Brown Cap Mushroom Virus (associated with Mushroom Virus X) prevention 01/15 Use of chemical disinfectants in mushroom production 03/15 Understanding Trichoderma aggressivum in bulk Phase 3 compost 04/15 Fungal diseases of mushrooms and their control HDC factsheets: Factsheet 11/07 Mushroom Virus X HDC grower summaries & reports: See HDC website ( for M58, M51, M39a, M39b, M39c, M39d and M07 VOC 18

23 This research is funded from the European Union's 19 MushTV: Solutions for the mushroom industry to emerging disease threats from Trichoderma and Mushroom Virus X Understanding Trichoderma aggressivum in Bulk Phase 3 compost Seventh Framework Programme managed by REA Research Executive Agency FP7 SME 2011 Grant Agreement No MushTV Industry Context A highly successful mushroom industry in Europe generating 2 billion worth of quality produce every year However, this dynamic, competitive and technologically advanced industry is not immune to disease threats MushTV (a partnership of scientists, composters & growers) provides practical research based solutions to improve efficiency through reduced losses to disease Past Financial Impact Some of our customers have experienced severe problems with Trichoderma aggressivum over the years and estimated losses are in the order of 500,000 Belgium 19

24 20 T. aggressivum Background Initially associated with infections at spawning of Phase 2 compost in traditional bag, block and tray (in situ) systems Little was known about how T. aggressivum grew during spawn run in bulk Phase 3 tunnels Compost fully colonised with mushroom mycelium was thought to be less susceptible to T. aggressivum infection Yet, outbreaks across Europe where spawn run is typically in bulk tunnels, began to challenge this theory Overall Research Objective: To take an innovative approach to Trichoderma aggressivum epidemiology that challenges common perceptions on how T. aggressivum behaves and so gain a greater understanding of how the organism exploits the bulk phase 3 system to its advantage Research Objectives: MushTV investigated the epidemiology of T. aggressivum in bulk Phase 3 compost by studying: Growth in bulk phase 3 systems & impact on mushroom yield Distribution in the compost during tunnel emptying & transportation How infected particles are distributed and detected during bulk handling & growing operations Effective hygiene procedures during a disease outbreak This presentation is a summary of the key research findings 20

25 21 T. aggressivum Symptoms whitish mycelium (just like Agaricus) spores produced (often on exposure to light) spores stay white for a day or so within 3 5 days compost turns green ultimately large green sporulating patches Less obvious symptoms: Subtle increases in compost temperature Agaricus mycelium retarded looser mass Distinct & characteristic smell evident T. Aggressivum Epidemiology Growth during Bulk spawn run T. aggressivum inoculated at filling Phase 2 Typical 17 day spawn run (25 ± 1 O C) Compost artificially emptied UNMIXED T. aggressivum not visible at emptying Growth restricted to ca 1 m from inoculation Mushroom yield loss 100% from infected area Remaining tunnel compost produced high yielding (ca 30 kg m 2 1 ) mushroom crops BACK MIDDLE-BACK FRONT-MIDDLE FRONT TOP MIDDLE BOTTOM BACK Top 24% yield loss Middle 42% yield loss Bottom 100% yield loss T. aggressivum Epidemiology Impact of simulated bulk handling operations When compost was thoroughly mixed at tunnel emptying, the previously contained small T. aggressivum infection spread through all compost Mushroom yield from the whole tunnel was reduced by % Equipment handling T. aggressivum infected compost was shown to infect clean compost from an adjacent newly opened tunnel 21

26 22 T. aggressivum Epidemiology Implications for growing Phase 3 compost fully colonised with Agaricus shown to be susceptible to T. aggressivum infection Cropping trials indicated that handling Trichoderma infected Phase 3 readily dispersed the disease around the growing unit Particularly relevant where compost is mixed i.e. filling, ruffling or emptying Cross contamination on a growing unit from an infected crop to newly filled crops is likely to occur Monitoring & Detection Early detection & identification of Trichoderma infections are key Simple presence/absent tests Air fall out plates or swabs Compost fragment tests Sophisticated species identification Molecular real time PCR (now effective for detection from compost) For compost testing it is critical that THOROUGHLY MIXED, REPRESENTATIVE compost samples are taken Monitoring & Detection Critical to implement routine detection/monitoring procedures to validate efficacy of hygiene procedures: Air fall out plate (during tunnel emptying) and swab sampling Regular compost testing MushTV pilot studies at compost and grower facilities identified the ideal sample types and locations to test for infection If an outbreak occurs, heighten compost sampling frequency and test sophistication e.g. real time PCR Don t forget to validate post crop steam cook out procedures 22

27 23 New Volatile Diagnostics Agaricus and Trichoderma produce volatile metabolites that affect each other s growth MushTV compared volatiles produced in non infected and infected compost Showed different patterns after 12 days spawn run between healthy A. bisporus compost and that infected with T. aggressivum Potentially could lead to improved diagnostics with an early warning system for composters Key Recommendations: At Compost Facilities: Implement stringent hygiene procedures at all times Use routine monitoring procedures e.g. air fall out plates to verify efficacy If possible, fill/empty Phase 3 tunnels at different ends, & with dedicated equipment for each activity Remove compost debris & thoroughly clean, disinfect and rinse winches, conveyors & all compost equipment before use Steam cook out/pasteurise tunnels between batches of Phase 3 compost Key Recommendations: Haulage contractors: All equipment that moves between facilities should be cleaned, disinfected and rinsed (inside & outside) frequently as a minimum between every location Be careful to remove all visible compost debris Fill growing rooms load by load i.e. do not mix compost loads 23

28 24 Key Recommendations: At Growing Facilities: Implement stringent hygiene procedures at all times Segregate all machinery, equipment and personnel used to fill Phase 3 compost Thoroughly clean & remove compost from all equipment and machinery e.g. conveyors, filling heads prior to and after use Fill Phase 3 compost in isolation. Crops shouldn t be emptied at the same time and growing rooms should be closed Be vigilant in the critical 3 5 days after filling Phase 3 actively look for symptoms Steam cook out at the end of every crop C in the compost for a minimum of 8 hours Key Recommendations: Don t forget the less obvious! Spores and disease infected compost fragments can be readily dispersed around facilities Detection studies identified floors, corridors, canteen areas, pack sheds, matting, shelves, tunnel doors, door handles, computer interface panels, keyboards, telephones and even notice boards can all harbour viable T. aggressivum Knowledge Transfer Recap: Bulk spawn run potentially increases the risk of a small compost infection becoming a serious disease outbreak Phase 3 compost colonised with Agaricus is susceptible to T. aggressivum; infections can lead to 100% crop losses T. aggressivum can readily infect and colonise otherwise healthy, highly productive mushroom compost Processes of compost mixing & breaking up Agaricus mycelium can spread small infections through large compost volumes Contaminated equipment and machinery can infect clean Phase 3 compost Stringent hygiene procedures can clean equipment & facilities 24

29 25 VOC Thank you for your attention 25

30 This research is funded from the European Union's 26 MushTV: Solutions for the mushroom industry to emerging disease threats from Trichoderma and Mushroom Virus X Contract No.: FP7 SME MushTV: Suitable disinfectants to limit risks from Trichoderma and virus X Seventh Framework Programme managed by REA Research Executive Agency FP7 SME 2011 Grant Agreement No MushTV Disinfectants Trichoderma aggressivum and MVX can cause serious problems on compost yards and mushroom farms. Disinfection is the key technology to control diseases and make a clean start. Disinfectants Disinfectants differ according to the active ingredients they contain. Different active ingredients have a different mode of action. For particular applications, disinfectants differ in efficacy. 26

31 27 Disinfectants 12 Disinfectants based on different active ingredients were tested in laboratory conditions Formalin Quaternary ammonium... + aldehydes... + phenolics... + amphoterics Peracetic acid + hydrogen peroxide Hypochlorite Phenolics Gaseous ozone Benzoic acid Electrochemically activated water Thyme oil Laboratory tests Tested in normal concentrations and double strength at disinfection periods of 15 or 60 min. Trichoderma aggressivum and Agaricus bisporus tested as spores and vegetative mycelium Both organisms also tested when present in compost particles Results for Agaricus bisporus All disinfectants except gaseous ozone were able to kill both mycelium and basidiospores Except for formalin none of the disinfectants was able to kill Agaricus bisporus when present in compost particles 27

32 28 Results for T. aggressivum Conidiospores could be killed by all disinfectants except gaseous ozone. Mycelium could be killed by a limited number of active ingredients (formalin, a combination of quaternary ammonium and aldehydes and benzoic acid) None were able to disinfect compost particles Take home message! Results show; Spores from mushrooms and Trichoderma aggressivum can be killed relatively easily by most disinfectants. But! Mycelium in compost particles cannot be killed by disinfectants. Therefore... Cleaning away compost from machinery, nets and tunnels and on compost yards and farms is critical for good hygiene. Advice for mushroom farms; apply a proper cook out! Heat can kill the pathogens when present in compost. 28

33 29 Choosing a disinfectant Most importantly; Efficacy Mushroom spores and Trichoderma spores are most likely to be the main vehicles of infection. Compost particles can be washed away. Choosing a disinfectant Other important aspects Corrosivity Methods of application available Safety towards applicants Safety towards the environment Potential residues on the product Status of registration as a biocide Choosing a disinfectant Most important aspects Potential residues on the product Should not leave a residue Applies only to Peracetic acid + hydrogen peroxide Hypochlorite (and ECAS) Electrochemically activated solutions Status of registration as a biocide Both active ingredients are being examined by EU for registration 29

34 30 Efficacy under practical conditions Efficacy tested on infected surfaces for Peracetic acid + hydrogen peroxide Hypochlorite Electrochemically activated water Efficacy under practical conditions Efficacy tested on infected surfaces of Rubber Stainless steel Aluminium Cell mat Concrete Isolation panel Coated steel Efficacy under practical conditions Electrochemically activated water has poor efficacy. For all surfaces tested and for both pathogens Peracetic acid/hydrogen peroxide and hypochlorite have good efficacy. 30

35 31 Testing for residue Disinfectants applied to different surface types After 1 hour disinfecting time, surfaces were either rinsed or not rinsed. Tested for residue immediately after rinse, 3 hours after, 7 hours after and 24 hours after. Testing survival of residue Measurement by pressing test stick in a droplet of water on the surface Surfaces tested: Aluminium Cell mat Coated steel Concrete Isolation panel Rubber Stainless steel Residue of hypochlorite After flushing Within 1 hour no residue left (except minor residue on isolation panel) Without flushing the surface Aluminium free of residue after 1 hour Rubber, concrete and coated steel free of residue after 4 hours Cell mat, isolation panel and stainless steel free of residue after 8 hours 31

36 32 Residue of peracetic acid / H 2 O 2 After flushing After more than 1 but less than 4 hours no residue left on the surfaces except for minor residue on rubber. Without flushing the surface Concrete and coated steel free of residue after 1 hour All other surfaces virtually free of residue after 8 hours Belangrijkste punten Disinfectants will only work properly if materials have been thoroughly cleaned first You cannot disinfect compost particles When choosing a disinfectants, be aware of Corrosivity Possibility of residues being formed Risks for humans and the environment Ask advice from your supplier!! Detailed information is available in the factsheet Thank you for your attention 32

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46 42 Developing alternatives to peat in casing materials for mushroom production Ralph Noble, Andreja Dobrovin-Pennington John Elphinstone, Jennifer Hodgetts Black blocking peat Peat fines 42

47 43 Matured Bark Spent casing MushComb Casing Separator 43

48 44 PAS 100 Matured green waste compost Granulated rockwool slabs Spent coir 44

49 45 Sand and aggregate filter cakes Casing Trial at Farm A Water and air holding characteristics 45

50 46 Casing Water Tension at Farm A 800 flush 2 Water tension, hpa Control Rockwool SM casing Spent coir Bark flush Time, days Casing Trial Farm B Casing Trial 1 at Farm C 46

51 47 Casing Trial 2 at Farm C Casing Trial at Farm D Water tension in Harte casing at three farms 800 Farm A Flush 2 Water tension,-hpa Farm B Farm C Flush Time, days 47

52 48 Mushroom yields from different peat casings at three farms, kg/m 2 Farm/Trial A1 A2 B C1 C2 D1 D2 Everris Harte Topterra Mushroom yields from different casing treatments at three farms, kg/m 2 Material % v/v Peat + Sugar beet lime casing Harte Everris Topterra Farm/ A# A1 A2 B1 C# D1 A1 A2 C1 C2 D2* C1 C2 Trial Control none Bark Bark GWC GWC Spent casing 25 Bark GWC 6.3 # Data from M 53 * with ground chalk Material % v/v Average water volume during cropping, %v/v Peat + Sugar beet lime casing Harte Everris Topterra Farm/ A# A1 A2 B1 C# D1 A1 A2 C1 C2 D2* C1 C2 Trial Control none Bark Bark GWC GWC Spent casing 25 Bark 6.3 GWC # Data from M 53 * with ground chalk 48

53 49 Material% v/v Farm/ Trial Control none Bark 12.5 Bark 25 GWC 12.5 GWC 25 Spent casing 25 ph value of casings Peat + Sugar beet lime casing Harte Everris Topterra A# A1 A2 B1 C# D1 A1 A2 C1 C2 D2* C1 C Bark 6.3 GWC # Data from M 53 * with ground chalk 49

54 50 25% Recycled casing Control Netting between compost and casing 50

55 51 Bacterial blotch caused by Pseudomonas tolaasii Taqman PCR Pseudomonas tolaasii CT results in casings between 2 nd and 3 rd flushes. Brown: severe blotch; pale brown: some blotch; white cells: no blotch; grey: not tested. Material% v/v Peat + Sugar beet lime casing Harte Everris Topterra Farm/Trial A1 C2 D1 A1 C1 C2 D2* C1 C2 Control none Bark n.t Bark n.t Spent casing n.t Spent coir 25 n.t. - - n.t Rockwool 25 n.t. - - n.t Clay Bark 12.5 Clay Bark 6.3 GWC * with ground chalk - treatment combination was not examined 51

56 52 Conclusions from casing trials Casing produced from Everris blocking peat/fines Effect of bark at 25% in casing on yield variable; bark is suitable at 12.5% Green waste compost unsuitable at 25% but suitable at 12.5% Bark + Green waste compost, each at 6.3% also suitable Spent casing can be recycled at 25-33% - requires separating equipment or method Conclusions from casing trials Casing water stress greater in 2nd flush than in 1 st flush Casing water content should be at least 60% v/v Blotch affected by casing and related to Taqman-PCR Developing alternatives to peat in casing materials for mushroom production Ralph Noble, Andreja Dobrovin-Pennington John Elphinstone, Jennifer Hodgetts 52

57 Notes

58 HDC is a division of the Agriculture and Horticulture Development Board (AHDB)