Mushrooms, fungi, and breeding: towards new applications

Mushroom forming fungi are versatile organisms that are suitable for a wide range of applications. However, compared to plants, there is little research being done and the available knowledge is fragmented. By further improving breeding, we can exploit the true potential of mushroom forming fungi. We are consolidating available knowledge and bring scientists and businesses together. Together we are working on new, economically viable applications for mushroom forming fungi.

Wageningen University & Research has long been a world leader in mushroom breeding. We have a collection of thousands of mushroom-forming fungi. From various strains of these fungi we select the most suitable genetic material for each intended application and then use it in our laboratories for improvement by breeding.

Food and non-food applications

Thanks in part to our research, you can now find a wider variety of edible mushrooms in the refrigerated section of the supermarket. Mushrooms are also being used as  ingredients in many food products. Furthermore, new applications are opening up more and more possibilities for using mushroomforming fungi for non-food applications:

  • Natural, environmentally friendly technologies for purifying wastewater with fungi are rapidly developing as fully-fledged alternatives to chemical wastewater treatment;
  • Enzymes that are produced by certain fungi have been found to be highly effective in breaking down lignin in woody waste streams and releasing valuable sugars;
  • Fibres in mushroomforming fungi have a lot of potential as a raw material for products such as sustainable clothing;
  • Thanks to their relatively simple genetic structure and shorter life cycles, mushrooms are suitable model organisms for studying complex genetic processes that also occur in plants.

Contributing to high-value commercialisation of mushrooms

With its independent research, Wageningen University & Research promotes high-value commercialisation of mushroom-like fungi. Our fundamental research contributes to a better understanding of their genetics. This knowledge helps us to work with commercial enterprises to develop tailor-made technological routes for new applications.

Biodiversity

Our Plant Breeding department has a large collection of fungi that produce edible mushrooms (the collection contains more than 5,000 strains representing more than 125 species), with emphasis on the button mushroom (Agaricus bisporus), the oyster mushroom (Pleurotus spp.), and the shiitake (Lentinula edodes). Currently, additional species of (edible) mushroom forming fungi are actively collected and added.

Phenotyping of edible mushrooms

Unifarm has an experimental, climate-controlled cultivation facility in which edible mushrooms can be produced on pilot scale. The design of the facility produces a crop that is comparable to commercial production and reliable phenotyping (e.g. disease resistance, quality, harvest, etc.). The rooms within the facility are also suitable for closed cultivation of genetically modified strains, and for cultivation of fungi for novel applications.

Substrate utilisation by button mushrooms

Substrate (compost) is one of the main cost items in button mushroom production. Research is focused on the role played by vegetative mycelium in the decomposition of organic matter and the formation of mushrooms. This knowledge is used to improve the efficiency of the cultivation system. In addition, the biological variation in the collection is used to improve substrate utilisation by commercial varieties.

Cultivation: mapping traits in segregating populations

The mushroom researchers generate segregating populations for traits that are relevant to primary producers (yield, quality, disease resistance) or consumers (taste, bioactive compounds, etc.). These traits are mapped using SNP markers or GBS (Genotyping By Sequencing). Markers linked to traits are then used for selection in offspring. The sporeless oyster mushroom is one of the products which this research group has cultivated.

Button mushrooms as a model for studying meiosis

The button mushroom is represented by two compatible subspecies differing in the interchromosomal crossovers. In commercial lines and most wild isolates, the crossovers are mainly confined to chromosome ends, whereas in the other subspecies crossovers take place over the entire chromosome. Segregating populations are currently being used to study the mechanisms behind these two recombination landscapes. It is hoped that this will generate knowledge that will enable meiosis to be controlled in such a way that all combinations can either be multiplied or maintained.

Button mushrooms we buy in the shops are almost identical the world over. To find out why, read the article written by Wageningen mushroom expert Anton Sonnenberg for Atlas of Science: Why are all button mushroom cultivars similar?

Mushrooms and the biobased economy

The utilisation of lignocellulose is limited by the presence of recalcitrant lignin. Physical and chemical pretreatments are now being used to reduce/modify lignin and improve access to (hemi)cellulose. White rot fungi (including many edible fungi) selectively degrade lignin during vegetative growth and can therefore be used to commercialise lignocellulose in a low-tech, low-cost and sustainable way.

Genetic regulation of mushroom formation

Genes that are differentially expressed in vegetative growth and initiation of mushrooms (pins) are overexpressed or knocked out using Atum transformation (via crossover and CRISPR-Cas9). The aim is to unravel the mechanism behind mushroom formation, allowing growers more control over the formation of mushrooms, which in turn could lead to the commercial production of mushroom species that were non-cultivable up to now.

For previous publications of research on mushrooms, fungi and breeding, visit the Mushroom Research unit’s Research@WUR overview page.