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A plant, Musa textilis, of the banana family that is valuable for its hard fiber (also known as Manila hemp) and native to Borneo and the Philippines. Abaca is one of the strongest of the hard fibers. Commercially, it is known as Manila hemp. The…

One of the major plant hormones that plays an important role in plant growth and development. Abscisic acid (ABA) is ubiquitous in vascular plants; the highest levels are found in young leaves and in developing fruits and seeds. Abscisic acid is…

The process whereby a plant sheds one of its parts. Leaves, flowers, seeds, and fruits are parts commonly abscised. Almost any plant part, such as very small buds and bracts to branches several inches in diameter, and scales or sheets of bark, may…

An autonomous undersea vehicle that can be launched from submarines, surface ships, or aircraft to attack enemy submarines and surface ships. An acoustic torpedo is a sophisticated weapon. Its main components are a guidance and control system, a…

A major constituent of the cell walls of certain red algae, especially members of the families Gelidiaceae and Gracilariaceae. Extracted for its gelling properties, it is one of three algal polysaccharides of major economic importance, the others…

The techniques and methods used in plowing, harrowing, planting, tilling, harvesting, drying, storing, and processing of agricultural crops. Agricultural soil and crop practices seek to keep the quality and fertility of soils at high levels so as to…

Any of the deciduous shrubs and trees of the genus Alnus in the birch family (Betulaceae). There are approximately 30 species of alder, with 10 in the United States. Alders are widespread in cool north temperate regions and are also found southward…

The world's most valuable forage legume, Medicago sativa, also known as lucerne, and less often as purple medic, medica, snail clover, median herb, Burgundy hay or clover, and Chilean clover. Alfalfa is often referred to as the queen of forages. It…

A major constituent (10–47% dry weight) of the cell walls of brown algae. Extracted for its suspending, emulsifying, and gelling properties, it is one of three algal polysaccharides of major economic importance, the others being agar and…

A small order of flowering plants, division Magnoliophyta (Angiospermae), which gives its name to the subclass Alismatidae of the class Liliopsida (monocotyledons). It consists of three families (Alismataceae, Butomaceae, and Limnocharitaceae) and…

A relatively primitive subclass of the class Liliopsida (monocotyledons) of the division Magnoliophyta (Angiospermae), the flowering plants, consisting of 4 orders, 16 families, and less than 500 species. Typically they are aquatic or semiaquatic,…

The dried, unripe fruits (berries) of a small, tropical, evergreen tree, Pimenta dioica (P. officinalis), of the myrtle family (Myrtaceae). Allspice (see illustration), which is also known as Jamaica pepper, is a native of the West Indies and parts…

Prunus dulcis (also known as Prunus amygdalus or Amygdalus communis), a small deciduous tree of the order Rosales that is closely related to the peach and other stone fruit trees, and grown widely for its ellipsoidal edible seeds. The fruit of the…

An annual plant (seldom perennial) of the genus Amaranthus (family Amaranthaceae) that is distributed worldwide in warm and humid regions. Amaranth plants are botanically distinguished by their small chaffy flowers (see illustration), which are…

Collectively, members of the class Amphibia are facing massive reductions in total numbers, and the overall biodiversity of amphibians across the globe is under threat. Scientists have determined that global climate change and habitat destruction…

A class of the plant division Bryophyta, containing plants commonly called granite mosses. The class consists of one order and two families, the Andreaeobryaceae and the Andreaeaceae. The large tapered foot and short, massive seta of the…

Substances suitable for the nutrition of animals, including livestock and poultry feed and pet food. Animal feed includes plant and animal products and by-products as well as vitamin and mineral supplements. Livestock and poultry feed In formulating…

An annual herb, Pimpinella anisum (family Apiaceae), whose fruit is used to provide food flavoring and to make a distilled oil. Anise is one of the earliest aromatics mentioned in literature. The anise plant (see illustration) is an annual herb that…

A small class of the plant division Bryophyta, made up of plants commonly called hornworts. There is a single order with six genera. Gametophyte structure The gametophytes are flat thalli, often forming rosettes of uniform thickness (see…

An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Rosidae of the class Magnoliopsida (dicotyledons). The order Apiales (also known as the Umbellales) includes two major families: the Apiaceae, with about 3500…

Correlative inhibition of the growth of lateral (axillary) shoots exerted by the growing apical bud of the plant stem. Competition for growth occurs between plant parts. Strongly growing fruits and branches (organs) act as sinks that divert energy…

Permanently embryonic tissue involved in cell division at the apices of roots and stems, and forming dynamic regions of growth. These apical meri­stems, usually consisting of small, densely cytoplasmic cells, become established during embryo…

A deciduous tree, Prunus armeniaca, in the order Rosales that produces a simple fleshy stone fruit. The apricot is thought to be native to China; then it was distributed throughout Asia and Europe, and eventually North America, South America, and…

Substitutes for sugar (sucrose) in foods and beverages that provide intense sweetness with few to no calories. Artificial sweeteners are sometimes called low-calorie sweeteners, high-intensity sweeteners, noncaloric sweeteners, non-nutritive…

A white, crystalline compound, 1-aspartyl-1-phenylalanine methyl ester (APM), with formula (1). It is slightly soluble in water. Its sweetening properties were discovered accidentally in 1965 when the compound, a dipeptide, was produced as an…

A class of nonflagellate unicellular algae, commonly called diatoms, with boxlike silicified walls. Diatoms range in maximum dimension from 4 micrometers to more than 1 millimeter. The diatom wall or frustule (Fig. 1) comprises several interlocking,…

The branch of applied physics which deals with the motion of projectiles and the conditions governing their motion. Ballistics is, for practical purposes, subdivided into exterior and interior ballistics. Exterior ballistics begins at the instant a…

A fast-growing tree, Ochroma pyramidale (also known as O. lagopus), which is widely distributed in tropical America, especially in Ecuador. Balsa (Ochroma pyramidale; also, O. lagopus) belongs to the mallow family, Malvaceae, in the order Malvales.…

A fermented beverage produced from grain. Beer is a generic term used to describe alcoholic beverages made from cereal grains, especially barley (Fig. 1), in the form of malt. Ale, lager, porter, and stout are different kinds of beer made by…

Fungi that exhibit the natural phenomenon of bioluminescence (the ability of an organism to emit visible light). Bioluminescence is the emission of photons of visible light by living organisms via the chemical reaction of molecular oxygen (O2) with…

A deciduous tree of the genus Betula, which is distributed over much of North America, in Asia (south to the Himalayas), and in Europe. Birch trees are assigned to the genus Betula. They belong to the family Betulaceae (which also contains alders,…

An illness produced by the exotoxin of Clostridium botulinum and occasionally other bacterial members of the genus Clostridium, and characterized by paralysis and other neurological abnormalities. Botulism is a serious (though rare) condition caused…

A group of steroidal plant hormones, typified by the compound brassinolide, that produce effects on plant growth and development. Plant hormones are naturally occurring organic molecules that regulate multiple aspects of plant growth and development…

A food product made by churning cream. In the United States, butter is not defined by Standard of Identity in the Food, Drug and Cosmetic Act as are most foods, but instead it was defined in 1923 by an act of Congress. Butter must contain at least…

A genus comprising yeastlike fungi that cause a variety of human diseases referred to as candidiasis. All Candida species are single-celled yeasts that are ovoid in shape and 3–5 μm in size, and they multiply by a process called budding. Most of…

Common pigments, typically of yellow, orange, or red hues, that serve in both light absorption and the protection against too much light in photosynthesis as well as in the vision process. Carotenoids comprise a class of labile, easily oxidizable,…

The principal protein fraction of cows' milk. It accounts for about 80% of the protein content and is present in concentrations of 2.5–3.2%. The term casein, derived from the Latin word for cheese, caseus, was introduced into the scientific…

A linear polymer of (1→4)-linked β-d-glucopyranosyl units, and the most abundant of all naturally occurring substances. Cellulose is the main polysaccharide in living plants, forming the skeletal structure of the plant cell wall. Cellulose…

A dairy product made by selectively concentrating major milk components. Cheese is generally rich in flavor and contains high-quality nutrients. There are many varieties of cheese, all produced in the following general manner: Raw or pasteurized…

The generic name for any of the intensely green, blue, or purple pigments found in higher plants, algae, and photosynthetic bacteria that are an integral part of photosynthesis. Chlorophyll is the name given to any member of a group of important…

Products derived from the seeds of the tropical tree Theobroma cacao, which grows within a narrow belt along both sides of the Equator. There are three basic varieties: Criollo, which was native to Central and South America; Forastero, which…

A tropical evergreen shrub or small tree of the genus Coffea (family Rubiaceae), a native of northeast Africa and adjacent southwest Asia, cultivated for the seeds (coffee beans) of its fruit. Members of the genus Coffea (Fig. 1) grow mainly between…

Keeping perishable products at low temperatures in order to extend storage life. Cold storage vastly retards the processes responsible for the natural deterioration of the quality of such products at higher temperatures. Time and temperature are the…

Zea mays, also known as maize, a grain crop grown for its edible seeds (kernels). Corn (Zea mays) [Fig. 1] is an important cereal grass plant belonging to the order Poales (formerly Cyperales). The top corn-producing countries are the United…

Trees provide substantial benefits to the environment. In addition to improving air quality, reducing stormwater runoff, serving as a wildlife habitat, and sequestering carbon by absorbing carbon dioxide, trees also cool the atmosphere through shade…

A warm-season annual cucurbit (Cucumis sativus), originally native to India, which is grown for its edible, immature, fleshy fruit. The cucumber is originally native to India and is grown for its edible, immature, fleshy fruit (Fig. 1). The cucumber…

A burst of electromagnetic energy. In a military context—and the subject of this article—an electromagnetic pulse (EMP) is a transient electromagnetic signal produced by a nuclear explosion in or above Earth's atmosphere (Fig. 1). Though not…

Volatile, fragrant oils obtained from plants. Essential oils are distinguished from those known as fixed oils, which are mainly triglycerides of fatty acids. Essential oils have been obtained from thousands of plants (Fig. 1) and are designated and…

An alkene, formula CH2=CH2. Ethylene (see illustration) is a colorless gas with a boiling point of −103.8°C and a melting point of −169°C. Ethylene is the most-produced organic chemical in the world and is used to make hundreds of products as well…

A taxonomic domain consisting of the vast array of living and fossil organisms with complex cells in which the genetic material is organized into chromosomes [linear pieces of deoxyribonucleic acid (DNA) bound with histone proteins and visible as…

Important functional components of foods, belonging to a group of biological substance called lipids. Fats and oils are soluble in organic solvents such as hexane, petroleum ether, alcohol, and chloroform. They are insoluble in water. Fats and oils…

An enzymatic transformation of organic substrates, especially carbohydrates, generally accompanied by the evolution of a gas. Fermentation is a chemical transformation of organic substrates, especially carbohydrates, to alcohol or organic acids,…

An altered immunological reaction to a food substance to which people typically do not react. A food allergy is a hypersensitivity to a certain food or foods. Allergy to food is similar to that to other environmental allergens [substances (antigens)…

The application of engineering principles to process, store, distribute, and protect food products for human consumption. The field of food engineering is multidisciplinary in nature because it combines chemistry, physics, engineering sciences,…

Production of food with the aid of microorganisms, which may be yeasts, molds, or bacteria. Well-known examples of such foods are bread, cheese, beer, wine, vinegar, some sausages, vegetables, yogurt, and cultured milk (see illustration). Various…

The study of the physical, chemical, and biological properties of foods as well as the sensory, nutritional, storage properties, and safety of foods. Food properties are influenced by growing, harvesting, and slaughtering practices, preservation and…

Any pathological condition transmitted by contaminated food. Foodborne diseases and illnesses, which are instances of food poisoning, have a significant impact on public health. They occur when foods contaminated by pathogenic microorganisms (Fig.…

The application of biotechnological techniques utilizing fungi for agricultural purposes. Fungal biotechnology is applied in agriculture to promote plant vigor, to increase yields, and to reduce impacts of plant diseases, weeds, or invertebrate…

Pathological conditions resulting from invasion by pathogenic fungi. Fungi are microorganisms that fill many natural niches in nature. They form a diverse group of eukaryotic microorganisms, including an estimated 2.2 to 3.8 million different…

A eukaryotic kingdom of organisms consisting of the principal decomposers of ecosystems. Fungi are nucleated, usually filamentous, spore-bearing organisms devoid of chlorophyll. Although approximately 100,000 species have been described in the…

Photosynthesis is a key natural process utilized by plants and is necessary for proper plant growth. Specifically, photosynthesis uses light to manufacture chemical compounds, including organic compounds—primarily carbohydrates—that are derived from…

A glass- or plastic-enclosed structure that is used to grow plants under protected conditions. Greenhouses (also known as glasshouses) are transparent, enclosed, climate-controlled structures (Fig. 1) in which young, tender, or out-of-season plants…