How black truffle season started in Spain?

We are getting so many surface truffles, wormy, not ripe enough. Some say it has lacked cold. True, he has done a warm autumn and in Catalonia, a cool summer with the rains necessary for the proper development of truffles, so we expect a good campaign. And I say, if there are truffles up well should be deeper.
I got surprised by the prices paid to the harvester, very low, 50 € / kg in the first week in Barcelona. 400km further north in the French market in Carpentras, the first market of 21st november truffles were paid at origin from 150€/kg to 50 € / Kg, 80 € / kg on average. 140 kg were sold there that first week. This Friday I still have no prices for Barcelona, ​​but in Carprentas 80 kg were sold at a price from 80€ to 200 € / kg on average € 150 / kg.
As you can see in the picture from a catalan orchard, truffles harvested this week vary widely in maturity and faint aroma, which justifies the price. At this time means that even Burgundy truffle (Tuber aestivum and its variety uncinatum) that is the end of its season and therefore very mature, could be paid better than the black truffle.

Note also this funny picture of a truffle with a flat side because of the stone it grow attached.
Cheers,
Marcos S. Morcillo

Barcelona Truffle Tour 2015!

During the last years we had may people coming to Barcelona from overseas to be trained on truffle growing, most of them loved also to go out for dinner and taste truffle menus, enjoyed wild truffle hunting, etc. This is why we´ve decided to create an event where all these experiences meet in one: Barcelona Truffle Tour 2015 will be held in 17-21 february.

In fact we will be running a two morning growers workshop on IRTA research center, 25 minutes from Barcelona city, later in the week moving to Teruel region for three more nights, where there are more than 7.000 hectares of truffle orchards. We will be visiting  big successful growers and analyze in situ the key factors to reach high yields (tractors and other machinery used, substrates, etc). We will experience 2 truffle dinners, one of them in Can Jubany with 1 Micheline star, and also talk with truffle traders to analyze the supply-demand in the near future and finishing last saturday night visiting the largest truffle market in the bar of the train station at Mora de Rubielos, where around 15 tons of truffles are sold each season! Note that this is not a french truffle market, but in Spain, truffle hunters after a long day in the wild or orchards, meet with traders at dusk for a just beer (if truffle price is low) or dinner (if truffle price is nice) in bars to sell the harvest of the week.

All nights in spa hotels (like www.latrufanegra.com), although we´ll keep you busy, your will be able to enjoy them as well (to be paid at the same hotel).

I will be your tour leader if some of you want to join us :-

Can truffles reproduce asexually?

black truffle asexual stage, truffles conidia production

Many fungi have besides a sexual phase, another parallel asexual or anamorphic stage, which are able to produce asexual spores or conidia, that may act as dispersion units. These mitotic conidia (simply dividing by mitosis) have been described for Tuber borchii, T. dryophilum and T. maculatum group. In fact, “spore mats” have been found in 9 of the 16 lineages of Pezizales. So why not the other truffles could have them? These conidia are 1 / 3-1 / 5 of the meiospores size that is in the fruiting body of truffles, in some cases 1 micron compared to the 40 microns meiospores, and they are easier to spread by water or wind and facilitate that different genets and mating types meet and fruit. Likewise, they may act as spermatia (parts necessary for fertilization in sexual reproduction), for example these conidia would be produced on the surface by the mycelium and may be carried elsewhere (wind, arthropod or other animals) and in contact with the hyphae emerging from a mycorrhiza of “mating type”, may form the dikaryotic mycelium, the only one able to produce truffle fruit bodies.

truffle spores mats from Healy.

You can already start looking under clods of soil from your truffle orchard, small clusters of white hyphae, about one square centimeter size, and looking at them with magnifying lens look like dusty, like the image attached from Rosanne Healy paper.

The picture that heads this post is part of the new book we are about to publish about truffles and their cultivation (will keep you posted). Here you can see like any mycelium, in this case positive sex, may form conidia that once germinated, the new hyfa (also positive) when meeting another complementary type mycelium, for example, coming from a mycorrhiza (negative sex in the illustration) give rise to dikaryotic mycelium, the one able to form a fruit body.

We now know that several fungi excrete hydrophobins to create a liquid film around the mycelium that make easier for bacteria and possibly their own conidia to move on the ground. They are in fact the “highways” (without tolls 🙂 or “skating ice rink ” along which various substances move at speeds around 1 cm per day.

We do not know whether these conidia are able to form mycorrhiza, therefore in one of the papers I cite below, none of the spore mats used as mycorrhizal inoculum produced any mycorrhiza under controlled conditions.

If in the near future, we can grow these mitospores inoculum in the laboratory and produce them cheaply, a tremendously interesting truffle door would open.
As a practical conclusion, a soil with a high activity of insects or animals, can favor the spread of mycelia, conidia or spores of different mating types to favor fruiting, also farmers can help with a single tilling.

Cheers,

Marcos S. Morcillo

References:

– Urban A, Neuner-Plattner I, Krisai-Greilhuber I, Haselwandter K. 2004. Molecular studies on terricolous microfungi reveal novel anamorphs of two Tuber species. Mycological Research 108: 749-758

– Healy RA, Smith ME, Bonito GM, Pfister DH, GE ZW, Guevara GG, Williams G, Stafford K, Kumar L, Lee T, Hobart C, Trappe J, Vilgalys R, Mclaughlin DJ (2012) High diversity and widespread occurrence of mitotic spore mats in ectomycorrhizal Pezizales. Molecular Ecology. 22, Issue 6, pp 1717-1732Doi: 10.1111/mec.12135.

– Rosanne Healy. Fungal Diversity…Hiding in Plain Sight. THE MYCOPHILE, JULY-AUGUST 2014. http://harvard.academia.edu/rosannehealy

what percentage of truffle aroma comes from bacteria?

bacteria amb microbes from bianchetto fruit body.
truffle aroma and bacteria

We’ve talked in the past about the importance of bacteria living on the surface of truffles and how they affect the final flavor of truffles and possibly play a major role in the formation of certain volatile compounds that could even facilitate the relationship between tree and fungus .
A new research has been published, very elegant in its structure, analyzing the characteristic volatile compounds in bianchetto (Tuber borchii),  analyzing sulphur-containing volatiles such as thiophene derivatives, characteristic just in this truffle variety.

I say that the work is elegant in his essay, because it shows without a doubt that these volatiles come from bacteria: truffles treated with antibacterial agents fully suppressed the production of thiophene volatiles while fungicides had no inhibitory effect. They concluded that the synthesis of thiophene come from bacteria, not from the fungi.

These bacterial communities change from one soil to another and that is why each truffle flavor varies depending on where it has developed, their terroir. Moreover, we know that some herbicides such as glyphosate (Round-up) have bactericidal effect, so their continued use in truffle plantations can affect the flavor of truffles that fruit in those truffieres.

In anyone is interested to read the paper:

Richard Splivallo, Aurélie Deveau, Nayuf Valdez, Nina Kirchhoff, Pascale Frey-Klett, Petr Karlovsky. Bacteria associated with truffle-fruiting bodies contribute to truffle aroma. Environmental Microbiology, 2014; DOI: 10.1111/1462-2920.12521

In fact the main author has a patent on the biotechnological application of using truffle mycelium and microbes to generate truffle aroma.

Cheers,

Marcos S. Morcillo

how to analyze by myself the texture of my truffle soil?

triangle of Tuber melanosporum soil textures

In the previous post we commented on the types of soils in which black truffles develops naturally.
Perhaps one of the most crucial parameters when choosing a soil to grow truffles is the texture. In this triangle you have represented an area of ​​lighter color with textures where the black truffle fruits naturally. In fact, it is highly variable and wild black truffles occurs in virtually all types of textures, however, due to the tendency to compact soil in plantations (for example by the use of machinery), we do recommend not planting black truffles over the 30% clay.
There are a few home methods to know what percentage of clay, silt and sand have our soil. In this great link you will be able to do it at home allowing the different particles sizes to settle down, or with your own hands:

http://www.ext.colostate.edu/mg/Gardennotes/214.html

Cheers,

Marcos S. Morcillo

which are the best soils where black truffle grows naturally?

Black truffle grows in so many kind of soils. This is why a full soil test, although it give us some information, is not the most important analysis to look at before planting your truffle orchard. The black truffle soil profile and the soil type should not be forgotten.

In this map you can see the distribution of two of the most common soils on natural truffieres in Spain and south France, leptosols in grey and calcisols in yellow.

Leptosols are shallow over hard rock and comprise of very gravelly or highly calcareous material. They are found mainly in mountainous regions and in areas where the soil has been eroded to the extent that hard rock comes near to the surface. Because of limited pedogenic development, Leptosols do not have much structure. On a global scale, Leptosols are very extensive. Leptosols on limestone are called Rendzinas while those on acid rocks, such as granite, are called Rankers

Calcisols have substantial movement and accumulation of calcium-carbonate within the soil profile. The precipitation may occur as pseudomycelium (root channels filled with fine calcite), nodules or even in continuous layers of soft or hard lime (calcrete). Calcisols are common on calcareous parent material in regions with distinct dry seasons, as well as in dry areas where carbonate-rich groundwater comes near the surface.

The source of this map is the Soil Atlas of Europe, European Soil Bureau Network European Commission, 2005.

http://eusoils.jrc.ec.europa.eu/projects/soil_atlas/index.html

But there is nowadays so many databases where to get this soil maps for free. Check these links:

For catalonia

http://www.igc.cat/web/ca/mapageol_geotreballs_gt4.html

For Spain

http://www.igme.es/internet/cartografia/cartografia/geologico1000.asp

For Chile

http://www.ipgp.fr/~dechabal/Geol-millon.pdf#page17

For México

http://mapserver.sgm.gob.mx/cartas_impresas/productos/cartas/republica/geologia/republica.html

direct link to download the México soil map(10Mb):

http://mapserver.sgm.gob.mx/cartas_impresas/productos/cartas/republica/geologia/sgm2000.pdf

For UK:

http://mapapps.bgs.ac.uk/geologyofbritain/home.html

Word soil maps:

http://www.fao.org/soils-portal/soil-survey/soil-maps-and-databases/regional-and-national-soil-maps-and-databases/en/

Cheers,

Marcos S. Morcillo

How to trap the truffle beetle Leiodes in your truffle orchard?

The new truffle season is coming in Europe and the main problem in the orchards in central Spain is the beetle Leiodes cinnamomeus, who literally drills a good part of the production, especially associated with plantations producing enough truffle regularly year after year. Some of these plantations harvest half of the truffles affected, to be marketed at less than half price.
It is a plague that affects mainly truffles at the start of the campaign, before the cold arrives, although the lasts seasons we found this beetle nearly all winter.
Traps are being tested with chemical attractants, but not always with good results:

These days in Tasmania (where I had a great time at the AGM of the ATGA) I was talking to an expert in Leiodes, Ainsley Seago, proposed to use the traps they use to capture beetles to study, but bigger in size:

The idea is to tied to trees a net that should be at least a meter tall; it can be as wide as you want, though more than 2-3 meters may be difficult to handle. We can use flyscreen from the building materials store: http://www.bunnings.com.au/our-range/building-hardware/door-window-gate-hardware/fly-screens
… make sure it’s dark coloured; if it’s light coloured or white, most beetles will avoid it.

For the trough, the PVC rain pipe is easiest to set in the soil. However, if large PCV pipes are not available, you can use a row of aluminum foil “roasting trays” from the supermarket: http://www.amazon.co.uk/12-Large-Foil-Trays-Lids/dp/B0035FR1OA/ref=pd_sxp_grid_pt_0_0

Propylene glycol and ethylene glycol (with or without added water) will kill the beetles. However, propylene glycol will make mammals sick if they drink it. If you’re worried about dogs, pigs, or wildlife, use propylene glycol or put a grating (say “chicken wire” over the trough).

The net should be no more than 10cm over the ground as leiodids almost always fly low and close to the ground, particularly in warmer evenings or after rain.
Leiodes cinnamomeus adult beetles start flying in spanish orchards from mid september and october, so if we put now these traps we can probably get more adults before they start drilling into the truffles.

About natural pest control; Ainsley says there’s not a lot of things that like to eat big crunchy adult beetles in huge quantities. Maybe lizards could do the job. I know some truffle growers use them to control slugs and snails.

Cheers,
Marcos S. Morcillo

Higher orchard density make trees more sensitive to insect pests

Increasingly being made more density truffle plantations, especially in areas with high winter temperatures or summers temperatures quite high, where the black truffle can develop under certain conditions of “shadow”.
These days I read an article that caught my attention and could give some explanation in part to increased pests and diseases in black truffle orchards.
According to this work, the shadow generated by the high density of a culture acts as a signal that induces plant growth to reach the light, but this redistribution of resources for growth is counterbalanced by a decrease in activation capacity defenses.

Today I’m flying to Australia, where I will be visiting some orchards and attending the meeting that makes the Australian truffle growers Association at the end of the harvest season. There are many plantations over there that use higher densities, at least higher than the ones we do in Spain (200-300 trees/ha), moreover the natural vegetative rate growth creater those “shadow” conditions earlier…
Cheers,
Marcos S. Morcillo

Reference:
JM, Fernández-Barber G, Chini A, Fernández-Calvo P, Díez-Díaz M, Solano R. “Repression of jasmonate-dependent defenses by shade involves differential regulation of protein stability of MYC transcription Factors and their JAZ repressors in Arabidopsis”. Plant Cell. 2014; PII: tpc.114.125047.

Can too much rain cause early maturation of shallow truffles?

This week I went to take samples to quantify DNA in a black truffle orchard just half an hour from Barcelona city. The truffle grower came with his truffle dog and our surprise came when in a short time raised more than 1kg of “chapas” or shallow truffles. They had matured early, mainly by the effect of bites or insect galleries, so truffle aroma appears. Many of them were already rotten.
In the photo above you can see the reddish peridium and at detail emerging hyphae between the pyramids.
It has been a year with lots of rain in Catalonia without excessive heat. This must have caused much of truffle primordia to finally develope, even those superficial ones than in other years would have dried up in midsummer.
The same could have occurred in many wild truffieres so the wild boar is having a great time in the woods. A shame, because probably boars also find the deeper truffles that could have mature properly.
Surface truffles are always more sensitive to meteo and insects, as you can see in the following pictures, starting with those “cracks” in the soil surface that announce the truffle is growing underneath:

Cheers,
Marcos S. Morcillo

Micelia quantification, mycorrhizas and Lactarius and Boletus fruitings

This summer has been quite rainy and fresh in Catalonia, so the mushroom season is promising. The Boletus edulis from the picture where found one month ago at 1000m of elevation in the Pyrenees.
A few months ago a great Thesis was published in Barcelona by Herminia de la Varga who quantifies the porcini and saffron milk cap micelium along the year.
A statistically significant positive correlation was detected between the concentration of mycelia of B. edulis in the soil samples and the amount of short roots mycorrhizal with B. edulis. No correlation was detected between L. deliciosus number of mycorrhizal roots and mycelium amounts.
The most interesting issue is that they found a clear increase on the amounts of soil mycelium biomass during the coldest months of the year. For both species, the minimum mycelium quantity is just before or at the same time as the fructification period, which could indicate an allocation of resources to produce the sporocarps. After these fructification periods, they found the maximums of soil mycelium. In these periods, the temperatures are the lower and it is when the photosynthetic and respiratory activity of the host trees are lowered, with a reduction of the absorption of water and nutrients by the radical system. Mycorrhizal fungi depend on photosynthetically fixed carbon produced by their associated trees, which may drive fungal growth. If the fungi receive less inputs from the plant (when temperatures are the lowest), extraradical soil mycelium would need to forage for new resources and would grow to increase their absorption surface. This hypothesis is also consistent with the decrease of mycelium biomass in temperate months (spring and early summer), when the photosynthetic and respiratory activities of host trees are higher. The germination of the spores just after the sporocarp production season could also be related with this fact.

For B. edulis they also found that those plots with a higher number of mycorrhizas were the same that had maximum sporocarp production, but no relation between mycorrhizas and sporocarp production was detected for L. delicious.
At the end of this year we will have the results of our own research on quantification of Tuber melanosporum micelia along the year so we’ll see if this theory is true equally for black truffle.
Cheers,
Marcos S. Morcillo

References:
Herminia De la Varga Pastor. 2013. Traceability of the mycorrhizal symbiosis in the controlled production of edible mushrooms. Thesis. Barcelona.