Grist: If not for an underground love affair between the fungal and plant kingdoms, todays planet would be a far less hospitable place. Mycorrhizal fungi are critical for more varieties of crops than are bees nine out of 10 crops have roots that are encrusted with these fungal tentacles. The fungi rummage through soil, fetching water and nutrients and delivering them to the roots of crops and other plants, receiving carbon-rich sugars produced through photosynthesis in return. The fungi protect the...