Peanut is a type of legume and belongs to the botanical family Fabaceae (also known as the legume, bean, or pea family). Legumes have the ability to fix nitrogen in the soil, which means they can improve soil fertility and require less nitrogen-containing fertilizers.
Peanut grows underground and is native to South America. It is a popular snack food and is also used in a variety of dishes, such as peanut butter and peanut sauce. Groundnut are high in protein and are a good source of healthy fats, vitamins, and minerals. They are grown in many parts of the world and are an important crop in many countries.
Etymology
The word “peanut” is derived from the African word “pinda,” which means “goober.” The Spanish called the peanut “cacahuete,” which is where the English word “peanut” comes from. The scientific name for the peanut plant is Arachis hypogaea. The word “Arachis” is derived from the Greek word “arákhis,” which means “peanut,” and “hypogaea” means “under the earth.” This refers to the fact that the peanuts develop underground, unlike many other types of nuts that grow on trees.
Global statistics about peanut plant
According to data from the United Nations Food and Agriculture Organization (FAO), the top ten producers of peanuts in the world in 2020 were China, India, Indonesia, Nigeria, United States, Vietnam, Argentina, Brazil, Pakistan, and Senegal. These countries together produced over 75% of the world’s peanuts.
In terms of total production, China was the leading producer, with a total of 24.4 million metric tons of peanuts produced in 2020. India was the second largest producer, with a total of 11.6 million metric tons. The United States was the fifth largest producer, with a total of 4.5 million metric tons.
In terms of land area, China had the largest area dedicated to groundnut cultivation, with over 6.9 million hectares devoted to peanut production in 2020. India had the second largest area, with over 3.6 million hectares, followed by Indonesia with over 1.9 million hectares.
Botanical classification of peanut plant
The peanut plant, scientifically known as Arachis hypogaea, is a type of flowering plant. Within the family Fabaceae, peanuts are classified in the subfamily Faboideae, which also includes other legume crops.
The classification of the peanut plant is as follows:
Kingdom: Plantae (plants)
Subkingdom: Tracheobionta (vascular plants)
Superdivision: Spermatophyta (seed plants)
Division: Magnoliophyta (flowering plants)
Class: Magnoliopsida (dicotyledons)
Subclass: Rosidae
Order: Fabales
Family: Fabaceae (legumes)
Subfamily: Faboideae
Genus: Arachis
Species: Arachis hypogaea (peanut)
Botanical description of peanut plant
Peanuts are annual herbaceous plants that are native to South America and are widely cultivated throughout the tropics and subtropics for their edible seeds. Here is a more detailed structure-by-structure list of the botanical description of the peanut plant:
Roots
The peanut plant has a taproot that grows deep into the soil, reaching a depth of up to 1.5 meters (5 feet). The taproot is thick and spindle-shaped, with smaller lateral roots branching off from it. The root system is efficient at absorbing water and nutrients from the soil, which is important for the plant’s growth and development.
Stems
The peanut plant has a branching stem that is about 30-50 cm tall and is covered in fine, downy hairs. The stem is upright and slender, and it supports the leaves, flowers, and fruit of the plant.
Leaves
The peanut plant has narrow, alternate leaves that are about 10-20 cm long and have a characteristic fan-shaped arrangement. The leaves are attached to the stem by way of a petiole, which is about 5-10 cm long. The leaves are green and glossy and are adapted for photosynthesis, which is the process by which the plant converts sunlight into energy.
Flowers
The peanut plant produces small, yellow flowers that are about 1-2 cm in diameter and are borne on short stalks (peduncles) that emerge from the axils of the leaves. The flowers are self-fertile, meaning that they can pollinate themselves, and they are pollinated by insects such as bees. The flowers have five petals and a central pistil, which is the female reproductive organ of the plant.
Fruit
After pollination, the flowers wilt and the peduncles elongate, eventually burrowing into the soil and forming a pod (also called a “fruit”) that contains the seeds (peanuts). The pod is about 5-10 cm long and contains one to four seeds, which are surrounded by a thin, papery skin (testa). The seeds are the edible part of the peanut plant and are an important source of food for people and animals.
History of peanut plant
Peanuts have been cultivated for food for at least 3,500 years, according to fossil evidence. They were domesticated by indigenous people in South America, who selected for plants with larger seeds and easier-to-remove seed coats. They were initially grown as a source of food and oil, and were also used in traditional medicine and as a source of protein for animals.
Over time, groundnut spread to other parts of South America and was eventually introduced to other parts of the world through trade and colonization. In Africa, peanuts were introduced by Portuguese traders in the 16th century and have become an important food crop in the region. They are used in a variety of dishes, including sauces, stews, and soups, and are also consumed as a snack food. Peanut cultivation is an important source of income for many small farmers in Africa, and peanuts are also a major export commodity.
In North America, peanuts were introduced by Spanish colonists in the 18th century and are now grown in the southern United States, where the climate is suitable for their cultivation. Peanuts are an important food crop in the United States and are used in a variety of products, including peanut butter, snack nuts, and confectionery. They are also used as feed for livestock and as a source of oil for cooking and industrial uses.
The botanical ancestors of the peanut plant are thought to be wild peanuts (Arachis duranensis and Arachis ipaensis) that are native to South America. These wild peanuts are still found in parts of Argentina, Bolivia, and Paraguay, and they have small seeds and thick seed coats that make them difficult to eat.
Today, groundnut is grown in tropical and subtropical regions around the world, including in South America, Africa, Asia, and the United States. They are an important food crop and are a major source of protein and oil for people in many parts of the world.
Genetics of peanut plant
Peanut (Arachis hypogaea) is an allotetraploid plant, which means that it has four copies of each chromosome (2n = 4x = 40). It belongs to the Arachis section of the legume family (Fabaceae), which contains 31 species of plants, including diploids (2n = 2x = 20), tetraploids (2n = 4x = 40), and aneuploids (2n = 2x = 18).
The cultivated peanut is thought to have originated from a hybridization event between two diploid species, Arachis duranensis and Arachis ipaensis, which are native to South America. This hybridization event resulted in the formation of an allotetraploid plant with four copies of each chromosome. The cultivated peanut has many characteristics that are intermediate between its two ancestral species, including seed size and seed coat thickness. These wild peanuts have small seeds and thick seed coats that make them difficult to eat, and they have been domesticated over time through selection for plants with larger seeds and easier-to-remove seed coats.
The genome of the peanut plant is relatively small, with a size of about 550 million base pairs. Peanut genetics and genomics have been the subject of much research, and this research has led to significant advances in our understanding of the genetics and genomics of the peanut plant. For example, researchers have identified genes that are involved in the development of the peanut plant’s taproot, which is important for the plant’s ability to grow in soil. They have also identified genes that are involved in the production of seed coat color and seed size, which are important traits in peanut breeding.
One of the major achievements in peanut genetics and genomics has been the development of techniques for genetic engineering and plant breeding, which have allowed researchers to improve the yield and quality of peanuts. For example, researchers have developed groundnut varieties that are resistant to pests and diseases, which has increased the productivity of peanut crops. They have also developed varieties with improved oil content and nutritional value, which has increased the value of peanuts as a food crop.
Species of peanut plants
These species are native to South America and are found in various regions of the continent, including Argentina, Bolivia, Brazil, Paraguay, and Peru. Some of these species, such as Arachis hypogaea (cultivated peanut) and Arachis ipaensis (Ipa wild peanut), are important food crops, while others are used as forage for livestock or as ornamental plants. Here is a list of 31 species of peanut plants in the Arachis section of the legume family (Fabaceae), along with their common names and scientific names:
- Arachis cardenasii (South American wild peanut)
- Arachis chiquitana (Chiquitanan wild peanut)
- Arachis correntina (Correntinian wild peanut)
- Arachis cruziana (Cruzian wild peanut)
- Arachis duranensis (Duran wild peanut)
- Arachis glabrata (Smooth wild peanut)
- Arachis glabriscapa (Smooth-capped wild peanut)
- Arachis glabriscapopsis (Smooth-capped wild peanut)
- Arachis hypogaea (Cultivated peanut)
- Arachis hypogaea ssp. hypogaea (Cultivated peanut)
- Arachis hypogaea ssp. fastigiata (Cultivated peanut)
- Arachis ipaensis (Ipa wild peanut)
- Arachis jussieuae (Jussieu’s wild peanut)
- Arachis kempff-mercadoi (Kempff-Mercado’s wild peanut)
- Arachis magna (Large wild peanut)
- Arachis monticola (Mountain wild peanut)
- Arachis montivaga (Mountainside wild peanut)
- Arachis nordestensis (Northeastern wild peanut)
- Arachis palustris (Marsh wild peanut)
- Arachis paraguariensis (Paraguayan wild peanut)
- Arachis pintoi (Pinto’s wild peanut)
- Arachis praecox (Early wild peanut)
- Arachis repens (Creeping wild peanut)
- Arachis serrensis (Serrens wild peanut)
- Arachis stenosperma (Thin-seeded wild peanut)
- Arachis suaveolens (Sweet-scented wild peanut)
- Arachis sylvestris (Woodland wild peanut)
- Arachis tibare (Tibar wild peanut)
- Arachis trinervis (Three-veined wild peanut)
- Arachis valida (Valid wild peanut)
- Arachis villosa (Hairy wild peanut)
Cultivation and production technology of peanut
Peanut plants grow best in well-draining, sandy loam soils. These soils are ideal because they provide good drainage and allow the plants to develop strong root systems. Peanut plants are also able to fix nitrogen from the air, which means that they can use nitrogen from the atmosphere to meet their nitrogen needs. Here is a detailed step-by-step guide to the cultivation and production of peanut plants:
Preparation
Before planting, choose a location that has well-draining soil and full sun exposure. Groundnut plants are sensitive to waterlogging, so it is important to avoid poorly drained soils. It is also important to choose a location with a pH between 6.0 and 7.0.
Seed rate
The seed rate for peanut plants is typically around 15-20 kg per hectare. This can vary depending on the seed size and the seed rate recommended by the seed company.
Sowing
Peanut seeds should be sown in rows that are spaced about 60-75 cm apart, with seeds spaced about 7.5-10 cm apart within the row. Sow the seeds about 2-3 cm deep in the soil. Groundnut seeds should be sown in the spring or early summer when the soil has warmed up to at least 20°C (68°F).
Irrigation frequency
Peanut plants should be watered regularly to ensure that the soil is kept moist, but not waterlogged. Water the plants once or twice a week, depending on the weather and soil conditions. Use a watering can or a hose with a fine nozzle to avoid washing the seeds out of the soil.
Fertilizer application
Fertilizers can be applied to the soil either before planting or after planting, depending on the type of fertilizer being used. It is generally recommended to apply fertilizers in two or three split doses, with the first dose applied at the time of planting and the subsequent doses applied at intervals of about four to six weeks.
The rate of fertilization will depend on the type of soil, the type of fertilizers being used, and the crop requirements. It is generally recommended to apply a total of 50-60 kg of fertilizers per hectare for peanut crops. This can be divided into two or three equal doses, with each dose containing 20-30 kg of fertilizers per hectare.
Weeding
Peanut plants are sensitive to competition from weeds, so it is important to keep the area around the plants weed-free. Hand-weeding or hoeing can be used to remove weeds, or chemical herbicides can be applied according to label instructions.
Harvesting
Peanut plants are ready for harvest when the leaves begin to yellow and the peanuts are fully mature. This typically occurs about four to five months after planting, depending on the variety and the growing conditions. To harvest the groundnut, loosen the soil around the plants with a hoe or a fork and gently lift the plants out of the ground. The peanuts will be found in pods attached to the roots of the plants.
Storage
After harvesting, the peanuts should be dried and stored in a cool, dry place to prevent mold and spoilage. Peanuts can be stored in bags or containers and will keep for several months if stored properly.
Along with the production technology, it is important to monitor the pH of your specific soil and adjust it as needed to ensure that it is within the optimal range for peanut growth. Soil pH can be adjusted by adding lime to raise the pH or sulfur to lower the pH. It is also important to test the soil for other nutrients, such as phosphorous, potassium, and micronutrients, and to apply fertilizers as needed to ensure that the plants have sufficient nutrients for healthy growth.
Diseases, pests, and weeds of peanut plant
Peanut plants are susceptible to a range of diseases, pests, and weeds that can affect their growth and yield. Here is a general overview of these issues:
Diseases
Fungal diseases such as leaf spot and root rot can infect peanut plants and cause reduced growth and yield.
Viruses such as tomato spotted wilt virus and peanut stripe virus can be transmitted to peanut plants by pests and cause symptoms such as yellowing leaves, stunted growth, and deformities in the peanuts.
Other diseases such as Aspergillus flavus infection and white mold can also affect peanut plants.
Pests
Insects such as thrips, aphids, whiteflies, armyworms, cutworms, wireworms, and mole crickets can feed on and damage peanut plants.
These pests can cause symptoms such as yellowing leaves, stunted growth, and reduced yield, and can also transmit viruses.
Weeds
Weeds are plants that grow where they are not wanted and can compete with peanut plants for water, nutrients, and sunlight.
Common types of weeds that can affect peanut plants include pigweeds, morning glories, lambsquarters, crabgrass, Johnsongrass, foxtails, and horseweed.
To prevent or control these issues, it is important to practice good cultural practices such as proper watering, fertilization, and pest management, and to use proper herbicides and pesticides as needed.
Peanut breeding and biotechnology
Peanut breeding and biotechnology are important tools for improving the yield and quality of groundnut crops. Through these techniques, scientists can develop peanuts that are more resistant to diseases, pests, and environmental stresses, as well as peanuts with improved nutritional content and flavor.
One example of peanut plant breeding is the development of peanut varieties with resistance to aflatoxins, which are toxic compounds produced by certain fungi that can contaminate peanut crops. Aflatoxins can cause serious health problems in humans and animals, and they are a major concern for peanut farmers and processors.
By breeding peanuts with genes that provide resistance to aflatoxins, scientists can help reduce the risk of contamination and improve the safety of peanut products. This has been demonstrated through scientific research, such as a study published in the Journal of Agricultural and Food Chemistry, which showed that genetically modified peanuts with enhanced resistance to aflatoxins had significantly lower levels of the toxic compounds compared to non-modified peanuts.
Biotechnology can also be used to improve groundnut crops. For example, scientists have used genetic engineering to produce peanuts with enhanced oil content and improved amino acid profiles. These modified peanuts may have a number of potential benefits, including reduced trans fat levels and improved nutritional value. Studies have shown that genetically modified peanuts with enhanced oil content had higher levels of healthy monounsaturated fats and lower levels of saturated fats, as well as improved sensory qualities, compared to non-modified peanuts.
By-products of peanut
In terms of quality, peanut by-products should be free from contaminants and meet relevant safety and quality standards. They should also be stored and handled properly to maintain their nutritional value and shelf life. Here are some by-products of the peanut:
1. Peanut oil: This is extracted from the groundnut seed and is used as a cooking oil and in the manufacture of soaps and other personal care products. It is a good source of monounsaturated fatty acids and has a high smoke point.
2. Peanut meal: This is the residue that is left over after the oil has been extracted from groundnut seeds. It is a rich source of protein and other nutrients and is often used as a feed supplement for livestock.
3. Peanut flour: This is made from peanut seeds and is used as an ingredient in baked goods, sauces, and other dishes. It is a good source of protein and fiber and is often used as a gluten-free alternative to wheat flour.
4. Peanut butter: This is made from peanut seeds and is used as a spread on bread, crackers, and other foods. It is a good source of protein and healthy fats, and it has a creamy, nutty flavor.
5. Peanut hulls: These are the thin outer layers of the peanut seed that are removed during the milling process. They are a good source of fiber and are often used as an ingredient in animal feed and as a soil amendment.
6. Peanut bran: This is the outer layer of the peanut seed that is removed during the milling process. It is a rich source of dietary fiber and other nutrients, and it is often used as an ingredient in animal feed and as a soil amendment.
7. Peanut shell: This is the outer covering of the peanut seed that is removed during the shelling process. It is a good source of fiber and is often used as a fuel or as a material for making garden mulch and other products.
8. Peanut straw: This is the stalk of the groundnut plant that is left over after the seeds have been harvested. It is used as a feed for livestock, as a building material, and as a source of fuel.
9. Peanut protein isolate: This is a concentrated source of protein that is obtained from peanut seeds. It is used as an ingredient in sports supplements and functional foods, and it has a high biological value.
Advantages and benefits of peanut
Peanuts can provide a number of health, environmental, and social advantages and benefits. Some of the important ones are:
Health
Peanuts are a good source of protein, fiber, healthy fats, and a range of vitamins and minerals, including vitamin E, niacin, and folate. They are nutritious and healthful food that can provide a number of benefits when included as part of a well-balanced diet. Here are the health advantages and benefits of peanut:
1. May reduce the risk of heart disease: Peanuts are a good source of monounsaturated and polyunsaturated fats, which are known to be beneficial for heart health. Several studies have found that eating groundnut or peanut products is associated with a lower risk of heart disease, including a review published in the Journal of the American Medical Association that analyzed data from over 20 studies.
2. May help lower blood pressure: Peanuts are a good source of potassium, which is known to help lower blood pressure. A study published in the American Journal of Clinical Nutrition found that eating groundnut or peanut butter was associated with lower blood pressure in adults with hypertension.
3. May help improve blood sugar control: Peanuts are a good source of fiber and protein, which can help improve blood sugar control. A study published in the American Journal of Clinical Nutrition found that eating groundnut or peanut butter was associated with improved blood sugar control in people with type 2 diabetes.
4. May help with weight management: Peanuts are a good source of protein and fiber, which can help with weight management. A study published in the Journal of the American Dietetic Association found that people who ate peanuts as part of a weight loss diet lost more weight and had a smaller waist circumference compared to those who did not eat peanuts.
5. May reduce the risk of breast cancer: Some studies have found that eating groundnut or peanut products is associated with a lower risk of breast cancer. A study published in the American Journal of Clinical Nutrition found that women who ate peanuts or peanut butter had a lower risk of breast cancer compared to those who did not eat peanuts.
6. May reduce the risk of colon cancer: Peanuts are a good source of fiber, which is known to be beneficial for colon health. A study published in the American Journal of Epidemiology found that eating peanuts or peanut butter was associated with a lower risk of colon cancer.
7. May improve brain health: Peanuts are a good source of several nutrients that are important for brain health, including vitamin E, niacin, and folate. Some studies have found that eating groundnut or peanut products is associated with improved cognitive function in older adults.
8. May reduce the risk of gallstones: Peanuts are a good source of monounsaturated fats, which have been shown to reduce the risk of gallstones. A study published in the American Journal of Clinical Nutrition found that eating groundnut or peanut butter was associated with a lower risk of gallstones in women.
9. May improve skin health: Peanuts are a good source of vitamin E, which is known to be beneficial for skin health. Some studies have found that applying a peanut oil-based moisturizer to the skin can improve hydration and reduce the appearance of fine lines and wrinkles.
10. May reduce the risk of stroke: Some studies have found that eating groundnut or peanut products is associated with a lower risk of stroke. A study published in the American Journal of Epidemiology found that people who ate peanuts or peanut butter had a lower risk of stroke compared to those who did not eat peanuts.
Environmental
Peanuts are a sustainable and environmentally friendly crop that can provide a number of benefits when grown and used in an appropriate way. They can be grown in a variety of climates, using minimal inputs, and on degraded soils, and they can provide habitat for wildlife, income for small farmers, and a source of renewable energy. In addition, peanuts can help to reduce the need for synthetic pesticides and greenhouse gas emissions. Here are the environmental advantages and benefits of peanuts:
1. Can be grown in a variety of climates: Peanuts are a tropical plant that can be grown in a wide range of climates, including hot and dry regions. This makes them a suitable crop for farmers in many parts of the world.
2. Can be grown using minimal inputs: Peanuts are a drought-tolerant crop that can be grown using minimal inputs, such as irrigation and fertilizers. This makes them a sustainable and environmentally friendly crop.
3. Can be grown on degraded soils: Peanuts can be grown on degraded soils that are not suitable for other crops, as they are able to fix nitrogen from the atmosphere. This can help to improve soil fertility and prevent soil erosion.
4. Can be grown as a cover crop: Peanuts can be grown as a cover crop to protect the soil from erosion, improve soil structure, and suppress weeds.
5. Can provide habitat for wildlife: Peanut fields can provide habitat for a variety of wildlife species, including birds, small mammals, and insects.
6. Can provide income for small farmers: Peanuts are an important cash crop for small farmers in many developing countries, and they can provide a stable source of income.
7. Can be used as a source of renewable energy: Peanut shells can be used as a source of renewable energy, as they can be burned to generate electricity or used as a fuel for cooking and heating.
8. Can be used as a natural fertiliser: Peanut plants produce nitrogen-rich leaves and stems that can be used as a natural fertiliser for other crops.
9. Can reduce the need for synthetic pesticides: Peanut plants produce compounds that are toxic to certain pests, which can help to reduce the need for synthetic pesticides.
10. Can help to reduce greenhouse gas emissions: Peanut plants are able to fix nitrogen from the atmosphere through the process of nitrogen fixation, which can help to reduce greenhouse gas emissions.
Social
Peanuts can provide a number of social benefits, including improving food security, providing nutrition and education for children, and creating employment opportunities. They can also help to promote cultural diversity and support local economies. Here are some social advantages and benefits of peanut:
1. Can provide food security: Peanuts are an important source of food and income for many small farmers and their families in developing countries. They are a high-yield crop that can provide a stable source of food and income, helping to improve food security and reduce poverty.
2. Can be used in school feeding programs: Groundnut and peanut products are a nutritious and affordable source of protein that can be used in school feeding programs. This can help to improve the nutrition and education of children, especially in developing countries where malnutrition is prevalent.
3. Can be used in emergency food aid: Peanut products are a shelf-stable source of food that can be used in emergency food aid. They are easy to transport and have a long shelf life, making them a suitable option for providing food to people in crisis situations.
4. Can create employment opportunities: The peanut industry creates employment opportunities for farmers, processors, and other workers along the supply chain. This can help to stimulate local economies and improve the standard of living for people in the community.
5. Can promote cultural diversity: Peanuts are an important food in many cultures around the world, and their cultivation and use can help to preserve cultural traditions and diversity.
Side effects and disadvantages of peanut
Peanut can have a number of side effects and disadvantages, and it is important to consider these potential impacts when consuming groundnut and peanut products. Allergic reactions, weight gain, high salt content, contamination with aflatoxins, and potential for pesticide residues are all potential health concerns associated with peanuts. Environmental impacts, competition with other crops, spread of pests and diseases, loss of biodiversity, and potential for food waste are all potential environmental and social concerns associated with the cultivation of peanuts. It is important to consume peanuts and peanut products in a responsible and sustainable way to minimize these potential negative impacts.
Nutritional properties of Peanut
Here is a detailed list of the daily values for various nutrients based on a 2000-calorie-per-day diet, including the percentage of the daily value provided by 146 grams (around 5 ounces) of peanuts:
- Calories: 2000 calories per day (36% DV)
- Protein: 50 grams per day (28% DV)
- Fiber: 25 grams per day (14% DV)
- Fat: 65 grams per day (78% DV)
- Saturated fat: 20 grams per day (33% DV)
- Carbohydrates: 300 grams per day (12% DV)
- Sugar: 50 grams per day (4% DV)
- Vitamin E: 15 milligrams per day (45% DV)
- Niacin: 20 milligrams per day (24% DV)
- Folate: 400 micrograms per day (32% DV)
- Magnesium: 400 milligrams per day (24% DV)
- Phosphorus: 1000 milligrams per day (29% DV)
- Zinc: 15 milligrams per day (27% DV)
These values are based on a 2000 calorie per day diet and are intended to provide a general guideline. It is important to consult a healthcare provider or a registered dietitian for more specific recommendations based on individual needs. It is also important to note that consuming large amounts of peanuts can contribute to weight gain and other health concerns if not part of a well-balanced diet.
Conclusion
Peanut plants are a tasty and nutritious food that can provide numerous benefits when consumed and grown responsibly. While peanuts can have some negative impacts, such as causing allergies or contributing to weight gain, they are also a good source of protein, fiber, and healthy fats. In addition, groundnut can have environmental and social benefits, such as providing income for farmers and supporting biodiversity. To maximize the positive effects of peanuts, it is important to consume them in moderation and choose varieties that are grown sustainably.
