OK, so they’re not plants but every good gardener knows that mycorrhizae, the thread-like fungi that lace our soil, are of our best friends for soil health and plant growth. With that in mind, here are a few recent stories about fungi and mushrooms.
The Perils of Hunting for Truffles
Jason Horowitz, the New York Times’ Rome bureau chief writes about the highly competitive business of truffle-hunting in Italy. Competition is so cut-throat that some have taken to poisoning the dogs of known truffle hunters. Horowitz’s article focuses on 80-year-old Renato Tomassetti and his dog Bella, an energetic Lagotto Romagnolo, a stocky, curly-haired breed also known as Italy’s “Truffle Dog”. The article is lushly illustrated with photos by Stepanie Gengotti.
No fungi? No forests, no food, no future!
David Suzuki with contributions from senior editor and writer Ian Hanington writes about the importance of fungi to humans. Cheese, bread, wine, beer, kombucha and chocolate would not exist without fungi. It makes all these tasty items possible. In fact, almost all food production relies on fungi. Most plants need it to obtain nutrients and water. Trees and other plants in a forest connect through intricate fungal, or mycorrhizal, networks of tiny mycelium threads that transfer nutrients, water and information between them, and that facilitate decomposition, without which life couldn’t go on. All fermented foods — including beer, wine, chocolate, cheese, bread, soy sauce and tofu — require yeasts, a single-celled fungus. Fungi have also been indispensable in preserving foods. And cows and other ruminants need gut fungi to break down grass. This Guardian article reports that fungi are also responsible for many important medical breakthroughs and for a lot of carbon sequestration.
For such an important group of organisms, we know almost nothing about fungi. Until the 1970s, fungi were classified as plants. We now know they are closer to animals. “They’re really weird organisms with the most bizarre life cycle. And yet when you understand their role in the Earth’s ecosystem, you realise that they underpin life on Earth,” said Kathy Willis, director of science at the Royal Botanic Gardens, Kew, which leads “State of the World’s Plants and Fungi” assessments.
Growing Mushrooms without Pesticides
Ali Jones reports in Horizon, the EU research and innovation magazine, on how La Rioja in northern Spain is both a centre for mushroom growing and research into greener growing strategies. Growing mushrooms commercially requires managing humidity, temperature and light to produce a regular, quality crop while contending with pest control. For now, pest control means relying on pesticides, which are becoming expensive and, of course, have environmental risks. Pablo Martínez, an agronomist, was drawn to the specialist mushroom sector after a chance conversation with a former colleague. Based at the Mushroom Technological Research Centre of La Rioja (CTICH), Martínez manages a Europe-wide project to tackle the environmental challenges faced by the industry.
Mushrooms are grown on a substrate, or base layer, made of straw and animal manure, then covered with a thick blanket of peat known as the casing. Made up of partially decayed vegetation, peat perfectly mimics nature’s forest floors that so readily yield mushrooms. The depletion of precious finite peatlands is a global concern. These wetlands store more carbon than all other vegetation types in the world combined and their conservation is ever more important for countering climate change. “Mounting restrictions on peat extraction in European countries threaten the long-term continuity of peat supplies,” said Martínez. “We’re looking to develop a new product for growing mushrooms that could cut pesticide use by 90% while reducing the industry’s reliance on peat.” EU-funded research aims to to create a low-peat sustainable casing for cultivated mushrooms made from renewable materials sourced close to existing mushroom production. While the exact details are under wraps, it will combine with a substance known as a biostimulant to enhance the natural growing processes and strengthen the mushroom mycelium in their early phase, protecting them against disease without the need for chemical pesticides.
Meanwhile, in Norway, two mushroom enthusiasts have pioneered a project to explore whether the crop could be cultivated in food waste. The EU-funded initiative is called VegWaMus CirCrop.
How the world’s deadliest mushroom conquered California
Writing in Live Science, Ben Turner reports on the spread of the aptly-named death cap mushroom. The poisonous “death cap” mushroom (Amanita phalloides) is an invasive fungus whose fatal amatoxin accounts for more than 90% of deaths from mushrooms worldwide, but how it spread from its European origins to colonize every continent except Antarctica has long been a mystery. Now, a study published to the preprint server biorXiv, has found a reason why: the California version of the death cap can fertilize itself and produce perfect copies, sidestepping the need to mate before wafting its spores over an unconquered region.
“The diverse reproductive strategies of invasive death caps are likely facilitating its rapid spread, revealing a profound similarity between plant, animal and fungal invasions,” the researchers wrote in the preprint.
Adding fungi makes rosemary tastier
Finally, research from the Royal Horticultural Society (RHS), Vitacress Herbs and Royal Holloway has shown that the addition of mycorrhizal fungi to soil leads to increased production of essential oils in rosemary, making the plants more aromatic and flavorsome. Adding mycorrhizal fungi did not affect the shape or structure of the plant, just the production of the compounds that enhance the flavor and taste of rosemary. This means that home gardeners and trade growers will be able to produce rosemary plants with a consistent appearance but with the potential for extra flavor. The research was published in Life.
Gardening at Last 