High-throughput screening is not just for finding novel genetic traits anymore. It is also being used to find beneficial microorganisms in the growing field of “biologicals,” which could bring some innovative plant-health products to market in the next few years.

“We’ve always known about biologicals but didn’t have the technology to multiply and find out how relevant or how compatible with chemical compounds they were going to be. The field is opening up,” says Jim Beuerlein, technical advisor, Seed Enhancement Biologicals, Becker Underwood, Ames, IA, and former Ohio State University agronomy professor.

“We can now source and screen many thousands of potential biological actives in a very short time, similar to what our colleagues have done in plant breeding and ag chem for many years,” says Trevor Thiessen, president of Novozymes BioAg, Saskatoon, SK. “This has not been done before in ag biologicals and will accelerate our ability to bring effective biological products to market.”

“We’re learning a great deal more about how to manage living organisms in the soil profile as well as their benefits to crop growth,” says Marty Robinson, president, Advanced Biological Marketing (ABM), Van Wert, OH. “We’ve also seen growing acceptance of biologicals by growers, in part led by large crop protection companies.”

Bayer CropScience recently introduced Votivo, a biological nematicide, and Monsanto features the Harpin Alpha Beta protein for early plant growth and vigor in Acceleron seed treatment.

Over the next few years, Becker Underwood will focus on biobased seed enhancers, the first of which is Vault HP. In on-farm trials last year, soybeans treated with Vault HP (which combines a biofungicide and a patent-pending rhizobial inoculant) yielded an average 6 bu./acre more than controls. It also was tested widely with university cooperators in the Midwest and South. Soybeans treated with the biological showed improved root mass and higher levels of nodulation.

The biofungicide component helps suppress Fusariumand Rhizoctonia.Vault HP is applied at a rate of 2 fl. oz./cwt. of seed.

Novozymes, which developed the BioAg division in 2007 after it acquired the microbials company Philom Bios, focuses on biofertility products, including JumpStart, TagTeam and N-Prove.

JumpStart, a phosphate inoculant containing the naturally occurring soil fungus Penicillium bilaii, improves the availability and uptake of phosphorus in a variety of crops, including corn, soybeans and wheat. Novozymes launched the product first in Canada and then in the U.S. JumpStart can help reduce the amount of phosphorus that farmers need to apply. It gained a lot of interest when phosphate fertilizer prices soared in 2008, Thiessen says.

TagTeam, which has been used in a variety of pulse crops, combines rhizobia with the soil fungus Penicillium bilaii to produce what Novozymes BioAg calls a MultiAction inoculant. The soil fungus grows on plant roots and makes less available forms of soil phosphate available to the plant. Phosphate helps create and move energy for the nitrogen fixation process, Novozymes BioAg says.

N-Prove, a single-action inoculation containing one active microorganism for nitrogen fixation, is used in a variety of legume crops.

In development

The next wave of biologicals coming from Novozymes BioAg will be bio-pesticides. Biopesticides represent an untapped area, Thiessen says. “Before, we were exploring the potential of a few thousand microorganisms. Now we can look at tens of thousands.”

The first of the company’s biopesticides for corn and soybeans will likely be a biofungicide that could be applied along with the seed treatment. This biofungicide would not replace the chemical, but rather cover any gaps, Thiessen says.

Novozymes BioAg says it also is working to develop biological yield enhancers — which use beneficial microorganisms to improve overall plant health and vigor.

ABM will be marketing SabrEx, a biofungicide for corn selected from a Trichoderma strain newly discovered at Cornell University. In trials with crop consultants and seed companies last year, corn treated with the biofungicide averaged 9 bu./acre more than fungicide-treated corn without SabrEx, Robinson says. “Experience has shown that it will increase root mass in corn, including fine root hairs. This helps the plant use nutrients and water more efficiently.”

With SabrEx, medium nitrogen (N) rates may perform as well as high N rates, Robinson says. For example, 150 lbs. of N/acre with SabrEx could yield results that are similar to those achieved by applying 180 lbs. of N/acre without it.

ABM is developing a SabrEx line featuring five biological strains and expects to market it for corn, wheat and rice.

For the soybean market, ABM will market Excalibre SA — a combination of Excalibre (which blends three strains of Bradyrhizobia) and Trichoderma strains. The company tested this soybean inoculant widely last year, including areas of the country where inoculants are not normally used, such as Illinois and Iowa. Preliminary testing showed an average yield increase of 2.2 bu./acre over controls. More testing is planned for this year.

These companies acknowledge that some farmers are skeptical about biologicals. Beuerlein, for example, notes that in years past, some biologicals worked only intermittently and were expensive.

However, Thiessen says that the science has come a long way. The companies around today have established a good scientific basis for development, whereas 10 or more years ago, some companies did not put rigorous testing into effect.

“That’s the reason there is a healthy skepticism,” Thiessen says. “But we worked hard to understand the technology and launched our first product after 10 years of lab and field research.” Philom Bios had been established more than 20 years before it was acquired by Novozymes.

Biological challenges

Development of biological products, which have living organisms, presents various challenges. One challenge is to create a product that acts consistently across a wide range of soil conditions and environments. Another is to be able to multiply and package strains in a way that they survive and perform well in the field without being cost prohibitive. Yet another is to develop strains that are compatible with chemical compounds that growers already use.

Despite the challenges, these and other companies see potential for biologicals, including their use in crop rotations to help delay the onset of resistance to certain chemicals and to improve overall plant health and vigor.