2019-08-13

Truffle cultivation Truffle cultivation • Cultivation techniques • Ecological factors

Christina Wedén Uppsala University

The truffle project began in 1997 with the help of Gotland mycologist Elsa Bohus Jensen

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Gérard Chevalier, Christina Wedén, Chantal Dupré, Tom Michaels & Yoram Luzzati Clermont-Ferrand, France in March 1999

First truffle inventories with trained truffle dogs from France, 1999

Bagnoli truffle Burgundy truffle

Michel Jalade, Gotland 1999 Tuber mesentericum Tuber aestivum (T. uncinatum) Less commercial species In cultivation

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Production of Tuber melanosporum

• Dramatic decrease in production after the 2nd world war

• Mid 1800s: 1 500 000 kg sold annualy

• Beginning of the 2000s: 250 000 kg annualy

Périgord truffle, Tuber melanosporum. ”The black diamond”. The most cultivated truffle world wide.

Tuber melanosporum

• Knowledge lost in the two world wars, but also a fast change in how the rural landscape was used in agriculture. • Industrialisation • Development of more controlled truffle cultivation in Italy and France: Production of Annual I.N.R.A. tree seedlings inoculated with truffles before control of planting them truffle seedling production at Agri-Truffe Nursery, France

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Checking truffle mycorrhiza at home with the help of a stereo microscope. Checking the entire root system of young oak, Quercus robur, seedlings

Tuber aestivum mycorrhiza under the stereomicroscope (above) and microscope (below.

The new method of truffle cultivation, made it possible to grow truffles on land – and even on continents – where the species did not grow naturally. For example this Gotand truffle in New Zealand

Tuber magnatum, Alba truffle or Piemont truffle The most highly priced truffle Tuber borchii, Bianchetto Charity auctions – enourmous prices for a large size ”The small white” In successfull cultivation Individual truffle (not the true price per kg) Keeps its flavours better than other speices in preserved products

http://limestonehills.co.nz/truffles/

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2017 charity auction in Alba, Italy:

Tuber magnatum, Alba truffle or Piemont truffle The most highly priced truffle Tuber borchii, Bianchetto Charity auctions – enourmous prices for a large size ”The small white” In successfull cultivation Individual truffle (not the true price per kg) Keeps its flavours better than other speices in preserved products ”White truffle” Choiromyces venosus (stjärnhovstryffel, Kaiserpilz)

”Restaurant owner Meir Vaknin has reason to celebrate. At the end of last week he bought a white truffle with a weight of 1 kg from a lady in Bestorp.” Gérard Chevalier testing for soil calcium carbonate Östgöta Correspondenten with HCl 20 August 2007

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Burgundy truffle soils in France Burgundy truffle soils in Sweden

SAND SILT

Many natural truffle soils on Gotland displayed a different texture, with more sand, compared to what was previously known.

Monthly mean precipitation Monthly mean temperature Main season for finding A soil composition comparison between [mm] [°C] mature Tuber aestivum* Swedish and French T. aestivum sites fruiting bodies (exceptions French data from Chevalier and Frochot 1997 Month exist) Swedish data from Wedén 2004 Gotland Burgundy Gotland Burgundy Gotland Burgundy January 43.3 73.6 -1.1 2.7 ///////////////// February 32.6 69.3 -1.8 3.6 March 34.6 69.3 0.1 6.5 April 29.3 60.4 4.0 9.0 May 28.0 81.9 9.6 13.2 June 39.5 75.9 14.3 16.0 July 51.6 65.4 16.3 18.7 August 48.5 66.4 15.9 18.6 ///////// September 56.8 72.0 12.1 15.1 ///////////////// ///////// October 50.5 80.0 8.1 10.9 ///////////////// ///////////////// November 57.5 83.2 3.9 5.9 ///////////////// ///////////////// December 55.5 87.1 0.7 3.8 /////////////////

6 Tryffelguiden När finns det tryffel? Ibland är det svårt att veta vilken tryffel som avses. Prisuppgifterna inom Tryffel äts med fördel färsk. De kommersiella tryfflarnas säsonger sträcker 2019-08-13 parantes är ungefärliga europeiska priser som varierar beroende på tillgång sig från september till april. Säsongen för respektive tryffelart är den tid då och kvalitet. man hittar mogna tryfflar. I Frankrike och Italien är det förbjudet att sälja färsk tryffel utom säsong. Så kallad sommartryffel som saluförs maj-sep- tember har medvetet utlämnats då denna till största del utgörs av omogna om det står... kan det betyda… men det kan också betyda… tryfflar.

Vit tryffel Albatryffel • Bianchetto (5000 kr/kg) (Tuber magnatum) • Någon mindre kulinarisk vit sporum & vin elano tertry 30 000 kr/kg och uppåt ädeltryffel, såsom trädgårdstryffel r m ffel ube • T T ub (inget marknadsvärde) l • er ffe b y tericum • 15 ru • Stjärnhovstryffel tr esen sept m rd ec er m – 15 a o d ub ja le (500-1500 kr/kg) ig 31 T Bour n & ér – l • gogn P t ffe etry k • Olika ökentryfflar k ry ffe in o it c l f e 1 ol e Bia rå s (500-1000 kr/kg) • n d nch n is g 31 et N k m a to y t u b – janu • a r t t ber ari y a p em T Z f n & e ec u e f s d b e e Svart tryffel Périgordtryffel • Bourgognetryffel (5000 kr/kg) g 1 fe e l l a m b r a • r b n • m u r u o d (Tuber melanosporum) • Slät svart tryffel (5000 kr/kg) v e a T r i m b r r u e t i c & s u m h b b e r e v i e 10 000 kr/ kg • Vintertryffel (6000 kr/kg) u o i A a o r p • u T r n s i e 1 s n • Kinesisk tryffel -flera olika arter • o m t 5 b d l r r a u c a e r j i f a a l c (omkring 5000 kr/kg) T s f i n u r e y m • n m e r – l r • Bagnolitryffel (2000 kr/kg) t b • e e 3 • a o

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f j e es s l v f en rå osu n s • N 1 juli – 30 sept ya Z ee r la be nd em & pt Planting the first Swedish truffières in 1999 86 A se us 15 tra i – lien un • Tu 15 j ber melanosporum •

Mulching experiment with plastic weave, chipped bark and straw.

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Seedling density: 1000 trees per hectare 2-3 meters between trees, 4-6 meters between rows

1999

2001 2003

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May 2004 Five years after plantation

• T. aestivum mycorrhiza in root samples from all truffiéres

• Brûlés visable

• 89% seedling survival

2004

First cultivated truffle in Northern Europe Tuber aestivum Gotland 2005

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Ulla & Claes Berglund Risungs farm Northern Gotland

3000 Swedish Quercus robur truffle seedlings planted in 2000-2001

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Truffle brûlés around the trees (Quercus robur)

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Truffle production in Sweden 2018 CULTIVATED TRUFFLES

• Two (out of seven) orchards established in 1999 in production: Annual production from production on- set in 2005, and 2011 respectively

• Three orchards from year 2000 in production. Highest production in the orchard with the most ”unlike” truffle soil – almost pure sand

• Tuber melanosporum production 2011 onwards: 8 latitudes north of the previous norhtern border! Maria Karlsson finding her first cultivated Tuber melanosporum on Gotland 2011

What can we improve?

…orchard management! But this orchard later produced a lot of truffles too.

Tuber melanosporum, Gotland 2011

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”My point is that when one decides to plant, one must avoid trying to duplicate exactly what happens spontaneously in the wild.

Rather, let’s envision the truffière to be like a meeting that we initiate involving several parties, where we serve as the referee.

And let’s never think that we can accomplish, without breaking a sweat, what nature can take decades to accomplish.”

-Bastien and Henri DESSOLAS Osez cultiver la truffe autrement!

To think about during the field trip Truffle production in aerated soils

• Which key differences can you pinpoint comparing natural truffle biotopes and truffle orchards in the same area?

• Differences or similarities in soil composition and soil structure? Importance of soil fauna?

• Why is nature ”better”? Time aspect? Vegetable bed (beetroot) on Gotland Truffles frequently develop in vegetable plots and flower beds

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Natural absence of ground vegetation by tree canopy coverage

Old hazel, Corylus avellana, forest meadow on Gotland

Management at planting Identified truffle production limitations: • tillage and soil amendment • Ground vegetation • pH 8 • Compact soils • soil structure and organic matter • pH < 7 • planning of the truffière depending on • Soil humidity: precipitation/irrigation management strategies: irrigation, site • Availability of truffle dogs availability, machinery etc. • protection from rodents, deer, grazing livestock • no grass or weeds around the seedlings

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Management during development MANAGEMENT METHOD AND THE EXPECTED TIME • soil cultivation in early spring to promote horizontal root TO THE START OF PRODUCTION development • weeding (possibly mulching) Management method Expected production start • irrigation if necessary/draught >25 days in spring – Free development 20-40+ years summer (possibly mulching) Mowed grass 10-20+ years • interactive plants of benefit to the truffle? • avoiding pests – from wild boars to ants Soil cultivation and black soil 5-10 years …PRESUMING: Follow-up: • high quality seedlings • suitable soil, structure, drainage, pH, water-availability • root samples to check mycorrhizal • soil cultivation with respect to seedlings, soil type and depth. Avoid turning the soil (plowing). development: the mycorrhizal • community is dynamic and ever changing understanding the conditions and requirements of the individual truffière • searching for truffles with trained dogs

Non-mycorrhizal roots (grass) versus mycorrhizal roots (oak, Quercus robur).

Non-mycorrhizal plant roots have dense root systems, while mycorrhizal roots do not need as many side roots as mycelia colonize the surrounding soil.

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Truffle dog – your quality control

Welsh Springer Spaniel Biscuit with truffle and assistant. Gotland 2007.

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