The little creatures in the Petri dish are tiny. To the naked eye they appear to be a tiny white cloud floating in a solution in the Petri dish. In reality, they measure about 300 micrometers — about the width of three human hairs.
The giant, slithering worm-like creatures look disgusting in the Petri dish, but they look downright ominous when magnified on the large screen that is connected to the microscope used by the researcher.
“These are plant parasitic nematodes,” explains Dr. Xiang Huang, a department manager with Novozymes in Research Triangle Park. “For them to be parasitic they need to be small enough to penetrate the roots of the soybean, which is where they do their damage.”
There are enough tiny creatures in that little cloud of nematodes under the microscope to devastate a soybean field. The creatures penetrate the root of the soybean plant and suck out the nitrogen, which reduces the number of seedpods the soybean can produce. Huang wants to make sure that won’t happen.
“They are our enemies,” Huang says matter-of-factly. “We are looking for microbials to kill the nematodes and protect the field.”
Scientists at a Novozymes facility in Research Triangle Park are designing naturally occurring microbial-based solutions to fight pests, like the nematode. But they are also looking at microbes to improve crop health and increase yields. Research is based on one simple fact: millions of microbes are already found in each gram of soil.
“The work we are doing is based on microbes, bacteria and fungi we know are living in the soil and can interact with plants,” says Thomas Schaefer, Vice President of Bioagriculture Research and Development with Novozymes. “Those types of interactions have been perfected through evolution over millions of years and they help with stimulating plant health, growth, and how the plant uses nutrients.”
The goal of the research is to find ways for microbial solutions to complement or replace traditional chemical pesticide treatments on farms to do three things: kill pests, increase plant fertility and increase yield.
Schaefer picks up a tomato plant that is sitting on a shelf in a small greenhouse near one of the Novozymes labs and points to the soil closest to the plant’s root. It’s called the plant microbiome and it’s a fairly new field of research.
“The working hypothesis is that we look closer at microbes closest to the plant because during evolution they have learned to work with the plant and stimulate growth and the plant has learned to work with the microbes,” explains Schaefer. “It’s a symbiosis type of relationship, it’s a give and take, and since evolution has done a lot of the work we want to take advantage of that.”
It turns out that all living organisms have evolved a symbiotic relationship with microbes. Microbiomes are found in the mouths, guts and skins of humans and animals. In plants, microbiomes are found in the soil.
The research begins with the soil that soil scientist Nathan Cude collects; then he begins classifying the variety of organisms found in the soil microbiome. His latest find comes from farms near Mount Olive.
“So after we culture the organisms from the soil, we are able to separate them out to individual organisms,” says Cude, holding up covered Petri dishes that have an array of different colors inside. “Each microbe comes out on different nutrient media and they come out in different colors.”
Once the beneficial microbes are identified, including those that will help plants take up nutrients, water, or protect against insects, weeds, or disease, the microbes are grown in controlled conditions. The microbes are not genetically modified in the research. They are simply highlighted, multiplied and then placed in an area near the plant where they can do the most good. In this case, the seeds are coated with the microbial solution.
Novozymes is partnering with Monsanto on the project. Novozymes produces the microbial solution, which is then delivered to Monsanto where the seeds are coated before planting. Roughly a half million plots around the country will use the specially coated seeds. At the end of the growing season, detailed reports about yield and other information will be gathered as well as the seeds, which will be brought back to Novozymes for analysis.
The research is groundbreaking but it is also urgent. That’s because there is a world food crisis looming on the horizon. The world’s population is growing rapidly, which means farms must significantly increase production on less and less land while also protecting the environment.
“This is an ecological issue we are dealing with,” says Sarah McHatton, a senior manager in Research and Development. “It’s not as easy as taking an anti-bacterial and putting it on a microbe, or an anti-fungal and putting it on a fungus, because the microbe is living and the plant is living and we have to see how they get along.”
McHatton says researchers are looking at very basic questions first; does the microbe always provide a benefit to the plant or does it help the plant only when it is stressed? There’s another research question that centers on whether the benefit from the microbe changes season by season.
“It is very complex because we have to look at the microbe and the plant as two living entities,” says McHatton.
“We have a very broad, open mind to which microbes will be the most helpful and will stimulate the plant,” adds Schaefer. “We isolate the natural microbes from soil and cultivate the natural microbes in our labs. There is no genetic manipulation; we are simply looking for microbes that naturally do what they are supposed to do. We put them on the seeds and test them in the field.”
After sinking the shovel or trowel into the ground to plant something, you end up looking at the dirt that is pulled up and asking yourself, “Just what is in dirt that helps plants to grow?”
We’ve all asked the question at some point. So, to keep things really simple, the answer is that there is a lot of 'stuff' in dirt — including rocks, sand, clay and organic matter. The United States Environmental Protection Agency says the average soil sample is 45% minerals, 25% water, 25% air, and 5% organic matter.
Dirt, or soil, makes up the outermost layer of the planet and topsoil is the most productive soil layer. Topsoil is also a very thin layer. Five tons of topsoil spread over an acre of land is only as thick as a dime.
Soil changes depending on where you live with the weather playing a big role in determining the combinations of rocks, clays and sand in the area and what kinds of plants, insects, and animals live there.
The weather in an area breaks down solid rock. Freezing and thawing, rainy and dry spells, and even wind variables all impact how quickly rocks are broken down into smaller and smaller particles. Different sized mineral particles — such as sand, silt and clay — give soil its texture.
Organic matter is the source of most nutrients in the soil; and those nutrients are released during the decaying process of organic matter. Living creatures also play a part in making up the soil because animals such as moles and earthworms help aerate the soil. Plant roots also add to soil development, breaking up rocks that become part of the soil. In addition, those plant roots help aerate the soil as well as hold it together to prevent erosion.
Over the span of thousands of years, all of those factors work together to create the dirt your new plant is going to call home.
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