An MSU scientist is finding out the plants he studies rely on organisms too small for the naked eye to see.

In the June 9 issue of the scientific journal "Nature," an MSU professor and other researchers explain how the interaction between microscopic fungi and many land plants could play a vital role in some of nature's most basic chemical processes.

"We need to understand how these fungi function in helping the plants," said Plant Biology Associate Professor Yair Shachar-Hill, who did the study with researchers at New Mexico State University and the Agricultural Research Service of the United States Department of Agriculture.

That knowledge could help improve overall environmental quality by encouraging the growth of certain fungi, which would reduce the need for harmful fertilizers, he said.

The microscopic organisms - called arbuscular mycorrhizal fungi, or AM fungi - are asexual and rely on a mutual relationship, or symbiosis, with plants to survive. About 80 percent of the plants on Earth are engaged in this relationship with the group of fungi, which includes 130 or 140 different species, Shachar-Hill said.

The fungi transmit minerals from the soil to plants, and in return the plants give them the sugars they need to survive.

Before this recent research, scientists had assumed the fungi were only important in providing plants with phosphorous, Shachar-Hill said.

But Shachar-Hill and his colleagues have discovered the symbiosis between a plant and the AM fungi that attach to its roots could account for more than a third of the plant's nitrogen uptake.

Shachar-Hill said nitrogen is the most important nutrient plants use to make proteins, and the nutrient most frequently in short supply in natural environments.

"The reason this hasn't been well-appreciated in the past is that in the absence of colonization (by the fungi), the plants are able to acquire nitrogen from the soil," said Peter Lammers, a professor of biochemistry at New Mexico State University who co-authored the "Nature" article.

The process of accumulating nitrogen from the soil has been stimulated by the use of synthetic nitrogen fertilizers in agriculture.

Lammers said the use of fertilizers has interrupted the symbiosis between the plants and fungi, and has resulted in a loss of plant diversity.

"As we've lost that diversity, we've become more and more reliant on chemical fertilizers," he said.

Nitrates from fertilizers in water runoff pollute waterways, causing adverse effects in the environment, such as the loss of certain fish.

"We'd like to use less nitrogen fertilizers," Shachar-Hill said. "What that means is making better use of what's there naturally."

Shachar-Hill said he and his colleagues will now have to convince people around the world that the research is important. He said although he has already heard from one researcher who wants to collaborate, he has yet to see widespread interest in the work.

He said the biggest challenge will be taking the results from a highly controlled lab environment first into a greenhouse setting and then into the field.

"Natural ecosystems and agricultural fields are much more complex to study because you can't control the conditions," he said.

Lammers, who has been collaborating with Shachar-Hill for about seven years, said there is every reason to think the transition into the field will be successful, and interest in the work has been limited only by the challenge of working with the fungi.

"Historically, it's been extraordinarily difficult to work with these organisms," he said. "It's just devilishly difficult to do."

Lammers said the ultimate goal is to be able to genetically modify the fungi to increase their level of interaction with plants, although Shachar-Hill said the fungi could be capable of higher levels already.