Interest in agricultural biologicals is increasing and the numbers are showing it: the biological industry grew to $6.2 billion in 2018. Inoculants on soybeans have been used for hundreds of years and wewe are just now starting to expand the use of beneficial bacteria and other organisms beyond Rhizobium species. As we learn more about soil bacteria, we also see the potential of new species to improve the health and vigor of crop plants.
The term “biologicals” is broad, meaning anything from beneficial bacteria and fungi to insects and plant extracts. Biologicals are loosely grouped into three categories: biofertilizers, biostimulants and biopesticides. A single species can be part of more than one of these categories.
Biofertilizers increase access to essential nutrients needed by the plant. An example is inoculants on soybeans. Biofertilizers can also unlock bound nutrients from the soil, such as iron or phosphorus, with Bacillus firmus, which increases the efficiency of crop inputs.
Biostimulants increase plant efficiency, vigor and health. An example would be Bacillus firmus that increases plant growth hormone production, water use efficiency, and tolerance to abiotic stress.
Biopesticides combat diseases or plant pests such as Bacillus thuringiensis, a novel trait in corn, or the use of Pasteuria nishizawae as a nematicide for Cyst Nematodes on soybeans.
Biologicals can have multiple modes of action. A single bacterium can release a number of compounds, such as plant hormones to stimulate growth, while also defending against pathogens or releasing acids that break down soil components into nutrients. They can be applied as a seed treatment or in-furrow during planting in a peat or liquid formulation. Tank mixing with herbicides in-crop is also an option. Better soil health is leading research on the benefits of soil organisms and their role in plant performance and health.
Biologicals work best as part of an integrated system for fertility and pest management. The impact of unpredictable weather events, such as drought or flooding, can also be managed with the use of biologicals. These products can help plants deal with abiotic stresses by increasing their water use efficiency and decreasing stress during adverse weather.
Jim Johnson is the president of Star Specialty Seed, a distributor of XiteBio® Yield+ for canola, based in Fargo, N.D.