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Mechanized systems of food and fiber production used in agriculture. The mechanized systems comprising agricultural machinery are utilized in numerous aspects of agriculture, including the initial tillage of the soil (Fig. 1), planting, cultural…

A deciduous tree (genus Malus) in the order Rosales, which produces an edible, simple, fleshy, pome-type fruit. Apples (Fig. 1) belong to the family Rosaceae, which includes many other deciduous fruits, including pears, peaches, and cherries. There…

Neonicotinoid insecticides are the most used insecticide worldwide and have been linked to the decline of pollinator insects. In 2018, the European Union banned the outdoor use of three neonicotinoid insecticides: clothianidin, imidacloprid, and…

Addition of elements or other materials to the soil to increase or maintain plant yields. For plants to develop, all the elements essential for growth must be supplied by way of the root system or, to a limited extent, through the leaves. The total…

The collective techniques for supplying nutrients and water directly to the roots of plants, without soil or other media. Hydroponics is concerned with the cultivation and growing of plants without soil or other media. Hydroponic systems (Fig. 1)…

Pathological conditions caused by pathogenic microorganisms in animals that are consumed as food. The introduction of an infectious disease into an animal population intended for food consumption by humans can have many negative outcomes, including…

The name (Spanish in origin) for the dried leaves, stems, seeds, and flowering tops of the hemp plant, Cannabis sativa, which can be smoked in cigarette form or in a pipe. Marijuana is the Spanish-derived name for the dried leaves, stems, seeds, and…

Fundamental principles governing the transmission of genetic traits, as discovered by Gregor Mendel. Mendelism is the term used to describe the basic laws of genetic inheritance (Fig. 1). These operating laws were formulated by Gregor Johann Mendel…

To better understand the nutritional effects (health benefits), chemical composition, growing conditions, and shelf life of microgreens, a team of researchers reviewed the science behind them in the Journal of Agricultural and Food Chemistry…

The study of biota that inhabit the soil and the processes that they mediate. Soil is a complex environment (Fig. 1) colonized by an immense diversity of microorganisms. As such, soil microbiology is concerned with the investigation of the…

The structure and composition of the hard fibrous substance that makes up the trunks and large branches of trees beneath the bark. Wood (Fig. 1) is composed mostly of hollow, elongated, spindle-shaped cells that are arranged parallel to each other…

It is estimated that 1 gram of soil can be inhabited by up to 109 microorganisms and approximately 60,000 bacterial species. Moreover, soil harbors a vast reservoir of antimicrobial agents, and soil-dwelling bacteria have played a key role in the…

Biocontrol, or biological control, is the natural or applied regulation of populations of pest organisms—especially insects—through the role or use of natural enemies. In other words, biocontrol uses living organisms to reduce and eliminate pest…

The biotechnology used in the creation of genetically modified crops is being expanded to encompass the bioengineering of plants that contain therapeutically important proteins and molecules that can be utilized in the manufacturing of…

Materials added to the soil, or applied directly to crop foliage, to supply elements needed for plant nutrition. These materials may be in the form of solids, semisolids, slurry suspensions, pure liquids, aqueous solutions, or gases.The chemical…

The trees, shrubs, herbs, bacteria, fungi, and animals, together with the surrounding air, soil, water, organic debris, and rocks (environmental substrate), interacting inside a defined boundary. Forests and woodlands occupy about 38% of the Earth's…

The science, art, and practice of managing and using the natural resources that occur on and in association with forested lands. Forestry is the management of forested lands (see illustration). It involves the planning and implementation of…

Bananas (Musa genus) are one of the world's most valuable and popular primary agricultural commodities. However, the most prevalent naturally occurring bananas, that is, those of the Cavendish variety, are being severely decimated by Panama disease…

Global climate change affects all areas of the Earth, with some regions experiencing greater impacts than others. In particular, the Arctic treeline—that is, the southern limit of the Arctic Bioclimate Zone—is being affected to various degrees by…

Forests absorb and store carbon. If this ability is hampered, then levels of atmospheric carbon will increase and global temperatures will rise, leading to potentially drastic climatic changes. In particular, deforestation (the permanent elimination…

Loss in the quality or productivity of soil that is often the result of human activities, such as agriculture practices, deforestation, mining, waste disposal, and chemical spills. Soil degradation is attributed to changes in soil nutrient status,…

New regulations by the U.S. Food and Drug Administration (FDA) that went into effect on January 1, 2017, banned the use of antibiotics as feed supplements to help livestock and poultry grow faster. The new rules, prohibiting the over-the-counter…

Because of nutrient-poor soil and the high cost of fertilizer, farmers in parts of Africa often produce only one-fifth to one-tenth as much corn (maize) per hectare as farmers in the United States do. Over time, farming in Africa and elsewhere in…

Wildfires are known to emit large amounts of gaseous and particulate pollutants. In an effort to identify and quantify these pollutants, researchers took their instruments to the skies where they sampled and analyzed smoke plumes from aircraft…

The pure and applied science that is concerned with botany and management of crop and ornamental plants for utilization by humankind. As it relates to plants, agricultural science concerns itself with the application of scientific methods to…

The art and science of crop and livestock production. In its broadest sense, agriculture comprises the entire range of technologies associated with the production of useful products from plants and animals, including soil cultivation, crop and…

Many trees enjoy extremely long lives in comparison to humans and other animals. Yet one group of trees, the bristlecone pines, stands out as the most ancient of all, with individual trees that commonly live for thousands of years, including one…

Any species of the genus Ilex. The American species of holly (Ilex opaca) attains a maximum height of 40–50 ft (12–15 m) and has evergreen leaves. American holly grows naturally in the eastern and southeastern United States, close to the Atlantic…

Lama glama, a member of the camel family (Camelidae) found only in South America. The llama (see illustration) is an artiodactyl, or even-toed ungulate, belonging to the mammalian family Camelidae. It has two toes on each foot. The llama is a…

A material useful for the mitigation, control, or elimination of plants or animals detrimental to human health or economy. Pesticides are formulated products that contain both active and inert ingredients. The active ingredients are the effective…

Between 2004 and 2014, the total phosphorus content of lakes and streams in the contiguous (lower 48) United States rose, according to surveys by the U.S. Environmental Protection Agency (EPA) reported in the journal Environmental Science &…

Biochar is charcoal made from biomass (organic matter used for energy). A process called pyrolysis, in which biomass is heated to high temperature in the absence of oxygen, produces biochar along with combustible gases (syngas) and oils (bio-oils).…

An herbaceous perennial, Rheum rhabarbarum or Rheum rhaponticum, of Mediterranean origin, belonging to the plant order Polygonales in older botanical classifications or Caryophyllales in newer classifications. Rhubarb (Rheum rhabarbarum or Rheum…

Concrete and steel have been the materials of choice for constructing high-rise buildings for over 100 years. Definitions of high-rise buildings vary, but according to the U.S. National Fire Protection Association high-rise buildings are 23 meters…

A rare animal, Vicugna vicugna, the smallest member of the family Camelidae, whose fiber is strong, resilient, and elastic, with exquisite fineness and beauty. The vicuna, or vicuña (see illustration), belongs to the family Camelidae in the…

Any of several leguminous plants, or their seeds, long utilized as food by humans or livestock. There are more than 40,000 varieties of beans, with only a small number of these being mass-produced for human or animal consumption. In particular,…

A medium-sized, spreading evergreen tree (Anacardium occidentale), native to Brazil, which is grown widely in the tropics for its kidney-shaped edible nuts and the resinous oil in the shells. Cashews belong to the family Anacardiaceae in the order…

Any member of the grass family (Poaceae or Gramineae) that produces edible grains usable as food by humans and livestock. Common cereals include rice, wheat, barley, oats, maize (corn), sorghum, rye, and certain millets. Triticale is a cereal…

A perennial herb, Cichorium intybus, with a long taproot; a coarse, branching stem; and a basal rosette of numerous leaves. Chicory (see illustration) is a member of the Asteraceae (Compositae) family with a history of cultivation dating back to…

A devastating bacterial infection of citrus trees, also known as huanglongbing or yellow dragon disease, transmitted by psyllids (jumping plant lice). Citrus greening disease, which was first reported in Asia during the late 1800s, is the most…