9.4: Benefits of "Green" Biotechnology

Introduction

Throughout history, farmers have selectively bred plants to achieve desirable traits, such as sweeter apples or larger corn cobs. However, this traditional method can be time-consuming and may inadvertently introduce unwanted characteristics. Green biotechnology offers a more precise approach to developing desirable traits in plants. These enhancements can include improved drought resistance, increased tolerance to pests and diseases, enhanced nutritional content in food, or the production of pharmaceuticals and industrial products.

Benefits of "Green" Biotechnology

Plant biotechnology is part of the "Green" biotechnology field. Green biotechnology, often called agricultural biotechnology, is the use of science and engineering on agriculture and the environment. It combines biology with technology to solve problems related to food production, sustainability, and environmental challenges. It is used to modify products, improve plants (or animals), or develop or engineer microbes for specific agricultural uses. Green biotechnology, in combination with traditional breeding techniques, can provide essential tools to farmers that can make agricultural production cheaper and more manageable.

There are many benefits of "Green" biotechnology with regards to plants and farming.

Improved crop production: Biotech crops can make farming more profitable by increasing crop quality and may in some cases increase yield. In addition, biotechnology can improve the health of crops. Some crops are engineered to tolerate specific herbicides without compromising their yields, making weed control simpler and more efficient. Other crops have been engineered to be resistant to specific plant diseases caused by certain microbes and insect pests, which can make pest control more reliable and effective, and/or can decrease the use of synthetic pesticides. Resistance to viruses, bacteria, fungi, insects or herbicides is known as biotic stress tolerance.

Biofortification: Biofortification is the process of increasing the nutritional value of crops through breeding, genetic engineering, or biotechnology. Biofortification focuses on the generation of micronutrient-dense crops through green biotechnology in order to improve the nutritional content in staple crops. Micronutrient-dense crops can effectively reduce vitamin and mineral deficiencies in populations who have limited access to diverse diets. Studies have shown its effectiveness, with iron-biofortified beans improving iron levels in Rwandan women and iron-biofortified pearl millet reversing iron deficiency in Indian schoolchildren. Golden rice, modified through biotechnology techniques to produce beta-carotene, a precursor to vitamin A (Figure \(\PageIndex{1}\)), was developed in 2000 to help combat vitamin A deficiency, a major cause of childhood blindness. Crops like canola, soybean, and corn have been improved with healthier oil compositions. Along with enhanced nutritional value, crops can also be generated to be resilient to environmental stresses, such as drought or pests. This dual benefit offers a promising strategy to address global malnutrition, improving the well-being of communities worldwide. However, biofortification comes with its challenges. Biofortified crops may be produced with heightened nutrient levels, but they need to be in a form the body can digest and absorb. These nutrients should also remain stable and retained throughout cooking, processing, and storage to ensure their full nutritional benefits are delivered. Another challenge lies in gaining acceptance and adoption of biofortified crops among both farmers and consumers, especially when traditional options are already well-established.

Environmental benefits: Insect-resistant cotton has significantly reduced the use of persistent, synthetic pesticides that may contaminate groundwater and the environment. Herbicide-tolerant crops are compatible with no-till or reduced tillage agriculture systems that help preserve topsoil from erosion.

Pharmaceuticals: Green biotechnology has emerged has a promising tool for vaccine production through its development of an edible vaccine. In this approach, genes encoding bacterial or viral antigens - the compounds that trigger an immune response - are introduced into plants. One of the most common ways of introduction is the bacteria Agrobacterium tumefaciens (for more information see Chapter 9.1 Applications of Green Biotechnology). The plant then produces these antigens in its edible parts (e.g. seeds, leaves, roots). When a person eats the plant, their immune system will recognize the antigen as foreign and launch a small immune response, thus building immunity to the antigen. Bananas, potatoes, tomatoes, rice, and lettuce are all being explored as edible vaccine carriers. Pathogens being targeted include those that cause widespread diseases, like hepatitis B, cholera, measles, and even COVID-19. Although edible vaccines provide the advantage of convenient and needleless administration, they are not currently as effective as normal vaccines as they are consumed and not injected into the blood. This is because in order to elicit an significant enough immune response, the antigens must survive the digestive process and be absorbed into the blood.

Production of phytochemicals: Green biotechnology is being used to genetically-modify plants to enhance their production of phytochemicals or to allow them to make new phytochemicals not normally found in the plant. Phytochemicals (Figure \(\PageIndex{2}\)) are naturally-occurring compounds found in plants that are not essential nutrients, like vitamins or minerals, but can have health-promoting properties. Phytochemicals are made by plants to protect themselves from pests, diseases, and environmental stress. In humans, phytochemicals act as antioxidants, anti-inflammatory agents and immune boosters. Common phytochemicals include the flavonoids and carotenoids. Using green biotechnology, tomatoes have been engineered to make higher levels of anthocyanins, a type of flavonoid, that can act as an antioxidant. The insertion of the stilbene synthase (STS) gene into the genomes of tomatoes and rice has resulted in the production of the antioxidant, resveratrol, in these plants. Outside of the farm, plant cells grown in tissue culture facilities can be used to produce specific phytochemicals in highly controlled environments, allowing for year-round production and avoidance of environmental variability.

Green Biotechnology Concerns

One key concern of green biotechnology is the potential transfer of novel traits to wild relatives. However, this potential transfer is carefully evaluated during the review and approval of genetically-engineered crops. Environmental impacts of engineered plants are also assessed, particularly regarding their effects on birds, mammals, insects, and other organisms, especially in the case of engineering insect or disease resistance traits. For example, studies have been conducted to ensure that bees are not adversely affected by the crops engineering to be resistant to pests. Food safety is another critical focus; newly introduced traits in green biotechnology plants undergo rigorous testing to assess potential toxicity and the risk of allergic reactions. These comprehensive evaluations help ensure that genetically engineered crops are both safe and effective for consumers and the environment.

To provide regulatory oversight of organisms derived through genetic engineering, the federal government developed a Coordinated Framework for the Regulation of Biotechnology in 1986. This framework spells out the basic federal policy for regulating the development and introduction of products derived from biotechnology. The policy has three tenets:

1. U.S. policy focuses on the product of genetic modification (GM) techniques, not the process of genetic modification itself
2. only regulation grounded in verifiable scientific risks is tolerated
3. genetically-modified products are on a continuum with existing products and, therefore, existing statutes are sufficient to review these GM products

Products made through biotechnology are regulated according to their intended use, with some products being regulated under more than one agency. The three principal agencies that have provided primary guidance on the experimental testing, approval, and eventual commercial release of modified organisms to date are the:

1. Animal and Plant Health Inspection Service (APHIS) - under the USDA
2. Environmental Protection Agency (EPA)
3. Food and Drug Administration (FDA) - under the Department of Human and Health Services (HHS)

APHIS protects US agriculture from pests and diseases. APHIS regulations concentrate on genetically-modified plants in order to ensure that they don't harm other plants or the environment. The EPA protects human health and the environment. In the biotechnology field, the EPA regulates biopesticides, biofertilizers, and genetically-modified crops that produce pest-resistant compounds like the Bt toxin discussed in Chapter 9.1 Applications of Green Biotechnology. The FDA ensures the safety of food, drugs, and cosmetics. The FDA reviews genetically-modified foods for safety, proper labeling, and nutritional content.

The Future of Green Biotechnology

The future of green biotechnology is exciting and full of possibilities. Some examples include the development of climate-resistant plants that can survive droughts, floods, and extreme temperature by enhancing their abiotic stress tolerance, the continued creation of biofortified foods that are rich in specific vitamins, minerals, and antioxidants, and expansion of the use of plants in phytoremediation. However, some new areas are entering the field include the use of CRISPR-based systems to fine-tune desired plant traits (e.g. pest resistance, faster growth) with extreme accuracy. To read more about CRISPR, go to Chapter 8.1 Applications of Animal Biotechnology.

Glossary

Abiotic - non-living physical or chemical factors in the environment, like temperature, sunlight, or soil quality

Agriculture - the science and practice of growing crops and raising animals for food, fiber, and other products to support human life

Agricultural biotechnology - the use of scientific tools and techniques, like genetic engineering, to improve crops, animals, and farming methods; often called
"green" biotechnology

Antigen - a substance (usually a protein or sugar) that triggers an immune response in the body; often used in vaccines

Anti-inflammatory - a substance that reduces swelling, pain, or irritation in an organism

Antioxidant - a compound that helps protect cells from DNA damage caused by free radicals

Biofortification - the process of increasing the nutritional value of crops through breeding and/or genetic engineering

Biotic - the living components of an ecosystem, such as plants, animals, fungi, and bacteria

Carotenoid - a natural pigment found in plants that gives yellow, orange, or red color; many act as antioxidants; examples include beta-carotene, lutein

Crop - a plant that is cultivated and harvested for food, fiber, or economic purposes

Flavonoid - a type of phytochemical found in fruits, vegetables, and tea; known for antioxidant and anti-inflammatory properties

Genetically-Modified (GM) Crop - a crop whose DNA has been altered using genetic engineering techniques to introduce traits like pest resistance, herbicide tolerance, or improved nutritional content

"Green" biotechnology - a branch of biotechnology focused on developing genetically modified crops, biofertilizers, and biopesticides to promote sustainable farming

Pest - any organism that damages or interferes with crops, livestock, food, or property—commonly includes insects, weeds, fungi, and rodents

Pesticide -a chemical or biological agent used to kill or control pests, including insects (insecticides), weeds (herbicides), fungi (fungicides), and others

Phytochemical - a naturally occurring compound in plants that is not essential for life but may offer health benefits; examples include antioxidants

Vaccine - a biological preparation that stimulates the immune system to protect against a specific disease

Vitamin - an essential nutrient that the body needs in small amounts to function properly; examples include vitamin C, vitamin D