Beneficial Bacteria and Soil: Hidden Helpers Below Ground
Imagine losing twenty years of work in just a few days. In 2013, this happened to Australian farmer Robert Hinrichsen after a massive flood.
Hinrichsen’s company, Kalfresh, is one of Australia’s leading vegetable producers: a year-round business producing 1,400 hectares annually in the Queensland area. Since Hinrichsen and his father started the company in 1992, production thrived. But in 2013, Tropical Cyclone Oswald led to eight days of regional flooding. Over one-third of Kalfresh’s farmland was “catastrophically degraded,” he remembers. Yet Kalfresh Farms managed to rebuild its farmland using microbiology and management. This outcome was crucial for Kalfresh to survive – and it provides an example of one way to save the world’s soils.
"The right microorganisms are vital for soil to be viable over the long-term and for crops to flourish in a given area."
Robert Hinrichsen Farmer & Owner, Kalfresh Farms, Queensland, Australia
In 2013, the UN estimated that if soil continued to degrade at current rates, there were only 60 years left of enough fertile soil globally. Two years later, a 2015 FAO report confirmed the point, stating: “The world’s soils are rapidly deteriorating.” The causes include soil erosion, nutrient depletion, loss of soil organic carbon and soil sealing. But the FAO report also stated that the use of sustainable management and appropriate technologies can reverse this outcome. For many agricultural professionals, biological products can help save soils, allowing the crops within them to thrive.
is the minimum number of years it takes to form 2,54 cm of topsoil.
Source: National Audubon Society
Surviving a farming nightmare
Kalfresh rebuilt its farmland based on soil biology. Soil itself contains three structures: the physical (the soil itself, composed of rock, sand, clay and/or silt), the chemical (mineral nutrients) and the biological (beneficial and pathogenic microorganisms). Hinrichsen transplanted physical soil to his land, then added fertilizers with chemical-based minerals. But soil biology must be developed and maintained, he explains: “The right microorganisms are vital for soil to be viable over the long-term and for crops to flourish in a given area.”
Soils host a quarter of our planet’s biodiversity
The "good bacteria" that exist in soil have many functions. Beneficial bacteria convert chemicals like nitrogen, phosphorus, potassium and iron into usable forms for crops. Farmers can also sustainably dispose of crop protection discharge by using such bacteria in a Phytobac biological system. In this system, farmers clean their spray equipment using collected rainwater. This water is then drained over a waterproof pit filled with a substrate of soil and straw, providing an ideal habitat for microbial "volunteers." Bit by bit, the microorganisms break down crop protection residues and start degrading them. Clean wash water eventually evaporates from the substrate, thus returning to the water cycle. And good bacteria can also suppress plant diseases, promote general plant growth and maintain a moisture balance so that soil doesn’t erode.
To rebuild his fields, Hinrichsen started by adding chicken manure-based microorganisms and sowing grain crops, which are less demanding on soil since they require lower mineral levels. He also produced specific crops like chick peas, which would leave minerals in the soil around their roots, so it rebuilds the soil nicely. Chickpeas – and certain other legumes such as peanuts and soybeans – live in symbiosis with nodule bacteria, which improve nitrogen-poor soils and help maintain soil fertility. These bacteria also contribute to the synthesis of human and animal-important proteins in the plant without the need for expensive nitrogen fertilization. Finally, Hinrichsen was able to add biologic products with the bacteria genus Bacillus subtilis, which fixes nitrogen. “But no single process or product rebuilt the soil,” he adds. Instead, intensive management practices alongside the development of good bacteria strengthened the overall rhizosphere – the soil that is immediately next to and affected by plant growth and activity.
Fortunately, Hinrichsen had developed knowledge of plant and soil interaction over the last decade by attending educational seminars. “I was studying this topic already. Then Bayer Australia brought in professionals to explain, scientifically, what’s happening in the soil and what farmers can do to support it.”
Life below our feet
Experts in soil and biologicals provide a crucial source of information and knowledge for farmers like Robert Hinrichsen, whether they face acute farming emergencies, such as flooding, or they simply need to grow crops more sustainably and effectively. Overall, farmers gain deeper understanding of how to produce stronger crops. Another expert in soil and biologicals is Dave Lanciault, the CEO of Agricen Sciences in Frisco, Texas. Like Hinrichsen, Lanciault is fascinated by how stronger soil leads to higher and more bountiful harvests. There is yet, he says, even more to learn about what’s happening below the ground: “The Dean at one of our ag colleges once told me that we know more about what’s happening at the bottom of the ocean than we do about the soils in our own backyards. For me, that means the potential for discoveries is almost unlimited.”
different types of bacteria live in one gram of soil.
Source: National Audubon Society
He explains that healthy soil is teeming with lifeforms that sustain it. “One of the important ways that soil can remain viable involves gaining a deeper understanding of biologicals: the community structure of the microorganisms (like bacteria and fungi) that already exist in soil, and the microorganisms that can be added to augment those communities.” Biologicals in agriculture include two main categories: biological crop protection products and biostimulants. Both types of products come from natural sources, but Lanciault says the public may be more familiar with biological crop protection products, that generally mitigate pests that negatively impact crops. Biostimulants, in comparison, “aim at improving plant growth and health,” Lanciault adds.
Agricen works with agricultural clients worldwide in a variety of soil and climate conditions. “Visibly weak soil – compacted soil or soil with poor water penetration – is fairly obvious,” Lanciault says. “But in many parts of the United States, Australia and elsewhere, the problems can be subtler. For example, increased salinity contributes to soil pH becoming more alkaline. There may be nutrients in these soils, but they are trapped. They’re not in a form that can be retained in the soil or are available to the plant, so the plant suffers.”
Lanciault and his team develop biostimulant products that help farmers manage these conditions based on science fundamentals. For example, one of the most significant chemical processes on earth is nitrogen fixation: this process converts atmospheric nitrogen gas (N2) into a form usable by plants and other organisms. Lanciault explains that nitrogen fixation is conducted by a variety of bacteria, both as free-living organisms and in symbiotic relationships with plants. Biostimulant products, as well as practices aimed at promoting soil health, can enhance this process. “Managing soil health means we must influence a complex soil ecology, which requires integrated soil management practices.”
Lanciault states that farmers, landowners and even governments need to make an ongoing investment to maintain soil: “For example, the US Department of Agriculture has incentive programs to improve nutrient management practices. These practices have to be economically sustainable to be adopted broadly. So there’s an upfront investment to analyze the soil, and the investment to maintain and improve it.” The outcome, he confirms, is worth it. “We are talking about taking a long-term approach to managing the soil environment so it can sustain itself – and produce stronger, healthier crops.”
A broad perspective
Lanciault has a kindred spirit in Dr. Denise Manker. In 1995, she helped found AgraQuest, a biotech company that created some of the first commercial microbial soil solutions. In 2012, Bayer acquired AgraQuest, and today, Manker is an R&D fellow in biologics at Bayer. From her Sacramento, California office, she says that more attention is needed, holistically, to the matter of soil: “It needs to be normal that we think about soil health throughout the year.”
"Self-sustaining soil, greater crop yields, healthier plants with more nutrients and even cleaner water and land. With biologicals, farmers, consumers and the environment benefit."
Denise Manker R&D fellow in biologics at Bayer
Manker explains that researchers have already identified individual biologicals with proven soil benefits. For example, scientists at Bayer recognized Bacillus subtilis strain QST 713 as beneficial for colonization of plant roots and provides plants with increased access to nutrients and other soil resources. She also points out that multi-microbial solutions can combine tasks, such as dissolving phosphorus and providing better salinity tolerance. And there are also successful combinations of synthetic insecticides used with biologicals (such as Bacillus firmus) that improve productivity while protecting against nematodes in corn plants, for example. Bacillus firmus is a bacterium that multiplies in soil to ward off nematodes. The bacterium suppresses existing nematodes and prevents hatching.
Manker is particularly excited by news from her Australian and Brazilian colleagues, who are seeing spectacular results by diversifying soil microorganisms: "It’s not just yield and general quality. These are healthier plants, born out of healthier soil." These crops also have a longer shelf life, she adds. "If you have produce that can naturally survive up to ten to 14 days, whereas in the past it might only survive for seven days, you’re reducing crop loss." And there’s additional good news: "We’re just beginning to see how these 'healthy crops' have higher levels of iron, calcium and other minerals."
For Manker, working with biologicals means sustainable farming: "Self-sustaining soil, greater crop yields, healthier plants with more nutrients and even cleaner water and land. With biologicals, farmers, consumers and the environment benefit." She pauses. "We are really learning how to take care of the soil that is taking care of all of us."
Allies for Biological Growth (Q&A with Keith Jones)
Keith Jones is the Executive Director of the Biological Products Industry Alliance (BPIA). An environmental attorney by training, Jones previously worked for trade associations and environmental non-profit organizations as either general counsel or executive director.
Why was BPIA founded?
BPIA was started about a decade and half ago by just five member companies. Today, we represent more than 125 manufacturers of biological crop protection products as well as biostimulant manufacturers, marketers, distributors, service providers, growers and food processors.
How do biologics generally benefit soil and agricultural soils particularly?
Biological products can augment, reinforce or help revitalize the natural activities of the native soil microbiome. A healthy soil microbiome can more efficiently provide available nutrients for plant use, improve physical and chemical functioning of the soil, or help balance the microbial populations to better manage pathogen pressure.
Are today’s soils prepared to increase their agricultural output to feed ten billion people by 2050?
Resources such as land and soil are largely fixed. Incorporating biological products will help the system reach an ecological balance and reduce pest and fertility problems. A more sustainable production system to feed a growing population will be established.