Balance of nature: reasonable research (Introduction)

by David Turell , Sunday, January 26, 2025, 18:46 (4 days ago) @ David Turell

How fungi help plants:

https://knowablemagazine.org/content/article/food-environment/2025/mycorrhizal-fungi-he...

"The spores will spawn mycorrhizal fungi, the oldest and most widespread partner of plants — the two have lived and worked together for some 500 million years. Up to 90 percent of plants have mycorrhizae living among their roots (mycorrhizal means root-dwelling). In exchange for food, the fungi help the hosts obtain water and nutrients, ward off pathogens, and improve tolerance to drought. As a community, mycorrhizae form a subterranean pit crew for maintaining plant health, akin to the gut microbiome in the human body.

"Today, ecologists like Bever are wielding mycorrhizal fungi as nature-based tools for conservation. Done correctly, they say, inoculation with these fungi can help to revive endangered plants or ecosystems with less reliance on fertilizers and pesticides than other approaches. But there’s nuance: When introduced where they’re not welcome, mycorrhizal fungi can bring unexpected consequences that may take years to recover from.

"Seeing plants only from an aboveground perspective without considering the complex dynamics below ground can mean “missing half of the picture,” says Adriana Corrales, a mycorrhizal ecologist at the University of the Rosary in Bogotá, Colombia.

"In a healthy environment, plants and their mycorrhizal partners can find each other on their own. But when ecosystems are too degraded and the native mycorrhizae have all but vanished, researchers have to play plant-fungus matchmaker.

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"Most mycorrhizal fungi worm their filamentous bodies inside the root cells of plants, but one kind — called ectomycorrhizal fungi — lurks outside the cells, usually close to the root surface. These fungi, which prefer to associate with trees from temperate and boreal forests, may be a last-ditch solution for ancient black oaks in the cloud forests of Colombia. Black oak (Trigonobalanus excelsa) is a relict species that populated the Northern Hemisphere for millions of years; today it grows only in fragmented patches of forest due to logging for timber and clearing for cropland.

"Mycorrhizal fungi are classified into two main types. Ectomycorrhizal fungi (left) form a network called the Hartig net that penetrates the root, surrounding its outer cells and enabling the exchange of nutrients with the plant. Endomycorrhizal fungi (right) grow filaments that penetrate into the root cells; some form arbuscules where nutrients are exchanged. Colonized roots may also contain vesicles and bear the fungal reproductive structures called chlamydospores.

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"Fungi are also lending a hand in Hawaii, where many native plants found nowhere else in the world are struggling under the combined threats of climate change, fires, habitat loss and competition with non-native species. Fungal ecologist Nicole Hynson of the University of Hawaii is using mycorrhizal fungi to help critically endangered gardenias, woody trees most famous for their fragrant blossoms that were once woven into leis. In the case of one of the archipelago’s three endemic species, Gardenia brighamii, only 10 or so individuals remain in the wild despite conservationists’ best efforts.

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"So far, mycorrhizal inoculation looks promising. In early greenhouse experiments, fungi-fortified seedlings grew three times as fast as their uninitiated brethren, according to unpublished data. Hynson hopes that she’s giving young gardenias the best start in life for when they’re eventually transplanted in outdoor restoration sites.

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"Nowhere is the danger of mycorrhizae gone awry more salient than on the Galápagos Islands, where native flora are fighting a losing battle against agricultural crops that settlers brought to the islands in the 19th century. Much soil collection, many potting experiments and hours of spore observations under the microscope led ecologist Jessica Duchicela...to discover that these agricultural crops forged close ties with mycorrhizal fungi that she suspects arrived in the soil used to promote the growth of early crops. The imported mycorrhizae, she contends, have slowly terraformed the islands, making the soil more hospitable for their invasive partners and less so for the natives.

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"At the end of the day, conserving precarious plants and furnishing their specific fungal companions often go hand in hand. Most mycorrhizal fungi are obligate partners — they need their plant hosts to survive. In this way, they may be even more vulnerable to extinction pressures than the host plants, which can often limp along if their microbial partners are absent. “I’m a huge advocate of using mycorrhizae to protect plants,” says Corrales, “and using plants to protect mycorrhizae.'”

Comment: I doubt the Guardian would give this article big headlines. However, science is quietly aware of the current agricultural problems, as this article demonstrates. But among climatologists there is great disagreement as to the accuracy of the climate models predictive ability. There are so many factors which must be included.