James White is a plant pathologist at Rutgers University in New Brunswick, New Jersey.
He said researchers have learned in recent years to harness endophytes in certain grasses to make the plants resistant to disease, drought, and insects.
Such endophyte research is "big business," he said, especially for turf grassesthe sorts that adorn front lawns.
"The benefits are tremendous," he said. "It means no or little herbicide has to be applied, less water to be put on the plants, and few insecticides."
In grasses many endophytes boost insect resistance, White said. Scientists believe the endophytes release nitrogen-containing compounds known as alkaloids that often have a bitter taste.
Insects and animals learn to avoid plants that release alkaloids, which can cause adverse reactions when ingested.
For example, horses in the southwestern U.S. might eat sleepy grass (Stipa robusta). Eating the grass makes the animals stumble around and then fall into a deep sleep that can last for days.
Once they wake, the horses never eat the grass again.
Researchers studying the grass discovered that the endophyte-released alkaloid in sleepy grass is a cousin to the psychedelic drug LSD, White said.
In another study researchers found that an endophyte allows certain species of plant to thrive in the hot, volcanic soils of Yellowstone National Park.
"In that case the endophyte species in those small-space plants was required for tolerance to high temperature," Ganley said.
In grasses the endophyte community is limited to one or two species. But in trees a single pine needle can host tens or even hundreds of species, Ganley said.
According to White, endophyte diversity may be high in trees because an army of internal fungi may be required to thwart the myriad threats trees face from diseases and predators.
"Overall there's bigger protection. I think that's the concept there," he said.
In general, Ganley believes diversity is the key to the smooth operation of any ecosystem.
"If you lose one animal, that has a lot of impact on the ecosystem," she said. "And fungal species can potentially be the same."
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