How Can Biotechnology Meet the Challenges of Sustainable Agriculture?
The advent of biotechnology has greatly improved the ability of scientists to select viable microbes for use in sustainable agriculture.
The fermentation process can have a huge impact on the ability of the microbes to survive in the soil or on the surface of plants.
This is dire, since a UN Committee in 2019 reported that fully one-quarter of the world’s land had been rendered unusable, “threatening everything we eat, drink and breathe.”.
Threats to arable land include an increase in salinity, soil erosion, and the ravages of climate change, including drought and an increase in temperatures. This raises serious questions about how farmers are going to grow enough food to meet future demands.
Not surprisingly, sustainability in agriculture has become a concept that is recognized as vital for the long-term production of food. Moreover, it provides numerous opportunities for new markets for companies that help enhance sustainability.
Consumer demand for organic and natural food has been steadily increasing.
Since sustainable agriculture has changed from a trend to a necessity, increasing numbers of people consider themselves “green” throughout the world. For example, consumers throughout the industrial world eschew the use of food that contains genetically modified organisms (GMOs).
A survey by the Pew Research Center and the American Association for the Advancement of Science (the publisher of Science magazine) found that only 37% of the general public in the US considers GMO foods generally safe to eat, while 57% consider them generally unsafe..
Additional research suggests that consumers in other parts of the world feel even more strongly about avoiding GMO foods. Italian consumers rated “GMO-free” to be the 5th most desirable characteristic of food. Japanese consumers rated it 7th in contrast to only 17th of US consumers.
As part of their concern about healthy food and a healthy environment, such consumers are willing to pay more for food grown organically.
European consumers value food grown as part of an integrated pest management (IPM) system to such an extent that they are willing to spend more money on them. In the US, even the government’s USDA website claims that organic products have gone from being a lifestyle choice for a small share of consumers to being consumed at least occasionally by a majority of Americans. More than half of the people who responded to a 2018 survey were willing to pay higher prices for foods that had a less damaging impact on the environment (Food Literacy and Engagement Poll conducted at Michigan State University).
This trend is not limited to the product itself. Indeed, the willingness of consumers to pay a premium price is also observed for food in environmentally friendly packaging. This was true for 86% of those surveyed in Sweden, 81% for those in the US, and 67% of those in Germany.
The consumer desire for safe foods has also been driving agricultural practices in emerging markets. For example, the growing export market for Brazilian food products has contributed to a need to reduce chemical residues in them. As a result, the use of insecticides in at least half of Brazil’s sugarcane crop has been replaced with biological controls and provides a ready market for biocontrols.
Governments throughout the world are implementing policies for sustainable agriculture.
Scientists have devised ways to make plants that are more appropriate for sustainable agriculture by altering their genes using methods that do not involve the introduction of foreign DNA.
This type of gene editing is widely used throughout the world and is particularly appealing to create new kinds of crops, since it is easier and much less expensive than traditional GMO technology. European regulators have been more aggressive in its regulation of foods than the US in many ways. This may explain why about one-third of the world’s organic farming is located in Europe. In addition, the EU ruled that gene editing results in GMO in a similar way than traditional technologies, a view at odd with those of most scientists.
This is a particular problem for many African farmers who grow crops produced by gene editing. Indeed, African scientists and farmers have embraced the use of this technology to produce more sustainable crops, that means better suited for local climatic conditions and more resistant to pests and diseases. Unfortunately, with the advent of the EU’s ruling, they face the loss of their major export market.
This gene editing technology was pioneered in microorganisms and has been widely used to produce new strains with desirable traits. Therefore, companies that use gene editing to improve their microbes will have to reevaluate this strategy if they want to market in the EU.
Such major Asian markets as China and India have been investing widely in the research and adoption of biological controls. China implemented a national research program to reduce chemical fertilizers and pesticides in 2015 and capped the use of agricultural chemicals in 2020. The amount of land devoted to organic agriculture in China ranked third in the world in 2018 (Daxue Consulting, 2020).
While there is a huge market for sustainable products in China, foreign companies will have to compete with the country’s domestic companies. In addition, most Chinese consumers are sensitive to price and unwilling to pay the higher prices for imported food.
Sustainability is also making inroads in emerging markets such as Brazil. The country’s legislators worked to enable the quick registration of biological control agents to help Brazil’s organic growers.
Improving soil health is pivotal to sustainable agriculture.
Soil is a highly complex ecosystem, and soil health is a critical factor for the success of crops. This metric encompasses many factors that interact with each other: physical structure, capillarity, and the profile of microorganisms.
Optimizing agricultural soils for the plants’ use of water and nutrients is a key way to improve the sustainability of agriculture, and all of these factors need to be considered to optimize soils in this manner.
Water is the medium by which plants assimilate all of their nutrients, it is one of the reasons why water is so important for the growth of plants. Both soil water and soil air are critical for growing plants to have adequate nutrients.
Well-structured soil has large pores that have air, water, and nutrients stored in them.
When soil is subjected to unsustainable agricultural practices like intensive tillage, it can lose its structure and become compacted. When this happens, the pores in the soil shrink, and water and air remain near the surface, inaccessible to the growing roots.
Water molecules are attracted to each other (cohesion), and they can also be attracted to solid surfaces (adhesion). Cohesion enables the water molecules to be attracted to each other – a property known as surface tension. Capillarity is a key concept in the ability of soils to retain water and is a combination of surface tension and cohesion/adhesion.
This affects water management in the field, because water rises to higher levels in smaller soil pores. Soils with a fine texture have smaller pores and hold and retain more water than sandy soils, which have larger pores.
When farmers use this information, they are able to optimize the amount of water they add to the field. This limits waste and enhances agricultural sustainability.
Such changes in the soil also affect the activity and diversity of the microbes that live in it. This combination affects both the quantity and quality of food grown in this type of soil. Plants tend to produce at lower levels when grown in soil with poor structure and damaged microbial communities. In addition, the food from these plants is typically much less nutritious.
Remediating this problem involves adding mineral fertilizers such as nitrogen, which are expensive and often pollute the environment. Large quantities of organic matter are often added to these kinds of soils to improve them.
Practicing sustainable agriculture that provides a favorable environment for beneficial microbes is both better for the environment and cheaper in the long run.
Providing information to help farmers become more sustainable should increase their likelihood of buying microbes that help enhance this process.
Soil microorganisms are necessary for the growth of plants.
A large variety of microorganisms are part of a soil ecosystem that revolves around plant roots, which provide a lush surface known as the rhizosphere that enables the growth of many types of beneficial bacteria, fungi, and insects. These organisms are pivotal to maintaining the proper soil structure, providing nutrients that plants need for optimal growth, and helping plants to resist the incursion of pathogens and pests.
A broad category of microorganisms, plant extracts, and soil components are known as biostimulants. These substances and/or microorganisms are applied to plants or the rhizosphere to stimulate natural processes that enhance the uptake of nutrients, their efficiency of use, tolerance to abiotic stress, and therefore, improve crop quality.
A particularly critical group of biostimulants are known as biofertilizers. These microbes increase yields by improving the availability of key nutrients. These organisms typically interact with plants roots in a win-win relationship as they also benefit from root exudates.
The application of biostimulants has reduced fertilizer use by 25% and provided a combination that was as efficient as an application of 100% fertilizer.
While the air is full of nitrogen gas (N2), only mineral form of nitrogen is assimilable by plants. Fortunately, a wide array of symbiotic biofertilizers fix nitrogen from the air, and supply plants with ammonium. Most of these plants are legumes, including soybeans and alfalfa.
Without microorganisms to fix nitrogen in the soil, “the Earth would experience a catastrophic de-greening” according to a 2014 paper entitled Life in a World Without Microbes .
This is also true for microbes that solubilize phosphorus in the soil. Indeed, phosphorus is mainly complexed with other minerals and unavailable to plants.
Therefore, having microorganisms that solubilize phosphorous and improve its availability in the soil will make a significant contribution to the sustainability of arable lands.
Another category of valuable microbes are biocontrols that battle the pests and diseases of plants that pose an enormous threat to crops and can cause potential losses of 48%-83% if crop protections are not used . These microorganisms can substitute for pesticides in some cases.
A number of bacteria, fungi, and nematodes are routinely used to control pests and pathogens. Different strains of the bacteria Bacillus thuringiensis are used to control various types of insects, including the voracious Colorado potato beetles that can devastate crops. Gypsy moths destroy forests on a large scale, and fungus Entomophaga maimaiga is used to control these devastating moths. The versatile fungus Trichoderma viride is used to control Dutch elm disease. It is also used to treat incursions of bacteria and fungi on tree wounds.
The markets for biocontrol agents have been increasing dramatically – one estimate ranges from $594 million in 2009 to $1.09 billion in 2015 in Western Europe and North America alone (Frost and Sullivan, 2009).
Augmenting the soil with microbes to improve plant health has been practiced for centuries and has seen a resurgence in recent years. Almost 10 years ago, the American Society for Microbiology published a special document suggesting that microbes may be a sustainable solution to increasing agricultural production.
The fermentation process can have a huge impact on the ability of the microbes to survive in the soil or on the surface of plants.
Role of biotechnology in the use of microorganisms for sustainable agriculture
The advent of biotechnology has greatly improved the ability of scientists to select viable microbes for use in sustainable agriculture. In earlier eras, promising isolates were identified through the process of inoculating them on plants – a laborious and time-consuming procedure.
Selection of beneficial microorganisms
It is now possible to collect microorganisms from diverse habitats and look for genes that suggest that they could serve as biostimulants or biocontrols. These include genes for antibiotics, plant growth hormones, such as indole acetic acid, siderophores (compounds that bind iron and make it unavailable to pathogens), and chitinases (enzymes that degrade fungal cell walls).
A knowledge of these factors greatly enhances the odds that a strain will promote the growth of plants and has simulated research on the use of microorganisms for sustainable agriculture.
The ability to quickly screen potential biostimulants or biocontrols has become critical, since the use of GMO to produce desirable strains will meet with resistance from consumers.
Fortunately, the increase in the use of molecular biology techniques, such as high-throughput screening and microfluidics, increases the feasibility of screening microbes on a large scale.
Improvement in the production of biostimulants and biocontrols
The fermentation process can have a huge impact on the ability of the microbes to survive in the soil or on the surface of plants. Earlier generations of biostimulants and biocontrols sometimes suffered from technical problems that resulted in poor performance in the field. For example, the microbes were not always viable, which resulted in variable yields.
However, the advent of biotechnology enabled microbiologists to optimize the production of these organisms and ensure that repeated batches are stable and have higher numbers of viable organisms per gram with longer shelf lives.
Variables in the production of viable inoculants include whether they are freeze-dried or provided as liquid cultures. Screening these properties is particularly important, since different strains of the same species can behave differently in the field.
Having the ability to conduct reproducible fermentations greatly simplifies the process of determining which conditions provide the highest number of viable organisms.
The use of yeast-based nutrients as stable nitrogen sources for culture media has enabled the production of highly active microbial biostimulants that can be use to improve the sustainability of agriculture.