MYCORRHIZAE
Mycorrhiza Defined
The word mycorrhiza is Greek for fungus and root,
and that’s just what these mushrooms do. The fungi
live in and around plant roots, siphoning off carbohydrates like glucose and sucrose from the plants. In
return they send tiny, hair-thin hyphae (root-like filaments) into the soil around like a web to catch water,
minerals, and other nutrients on behalf of the plant,
effectively multiplying its root capacity several times
over and leading to turbo-charged growth.
There are thousands of different kinds of mycorrhizal fungi, but they divide roughly into two different forms. Ectomycorrhizae live in the soil around
the plant and are usually associated with trees and
woody plants. The mushrooms you see growing
around trees, including many you can eat like chanterelles, are the fruiting bodies of ectomycorrhizal
fungi, above-ground evidence of a complex subsoil relationship enabling the tree to connect more
closely with the earth it’s growing in. Then there are
the most commonly found group, the endomycorrhizae, or occasionally vesicular-arbuscular (VA) mycorrhizae, which live right among the cells inside plant
roots. They form close relationships with around 80
per cent of leafy plants, including vegetables like
tomatoes, broad beans, and strawberries. Though
they will die out where plants aren’t growing (for
example, in a compost heap or a bare patch of soil),
but when spores encounter roots they burst into
life, colonizing them and then sending out hyphae
hunting for food.
“We know
as little
about what goes on under our
feet as we do about the outer
reaches of the galaxy.”
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Maximum Yield USA | January 2017
Among the nutrients mycorrhizal fungi can draw
from the soil for their hosts are phosphorus, nitrogen, manganese, copper, and zinc. The fungi act
like a drawbridge against pathogens, making it
impossible for them to get into the roots. When a
plant is stressed, whether it’s because it’s too hot
and can’t draw up water fast enough, is growing
in the wrong type of soil, or was recently transplanted, mycorrhizae can help it recover and
thrive. Just like humans eat yoghurt to reinvigorate naturally occurring gut bacteria and treat an
upset stomach, mycorrhizae are like soil probiotics that help plants fight off diseases.