Cucurbita pepo Yellow Squash 3.jpg
   HOME

TheInfoList



OR:

''Cucurbita'' ( Latin for gourd) is a genus of
herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of t ...
fruits in the gourd family, Cucurbitaceae (also known as ''cucurbits'' or ''cucurbi''), native to the Andes and Mesoamerica. Five edible species are grown and consumed for their flesh and seeds. They are variously known as squash,
pumpkin A pumpkin is a vernacular term for mature winter squash of species and varieties in the genus ''Cucurbita'' that has culinary and cultural significance but no agreed upon botanical or scientific meaning. The term ''pumpkin'' is sometimes use ...
, or gourd, depending on species, variety, and local parlance. Other kinds of gourd, also called bottle-gourds, are native to Africa and belong to the genus '' Lagenaria'', which is in the same family and subfamily as ''Cucurbita'', but in a different tribe. These other gourds are used as utensils or vessels, and their young fruits are eaten much like those of the ''Cucurbita'' species. Most ''Cucurbita'' species are herbaceous vines that grow several meters in length and have tendrils, but non-vining "bush" cultivars of ''C. pepo'' and ''C. maxima'' have also been developed. The yellow or orange flowers on a ''Cucurbita'' plant are of two types: female and male. The female flowers produce the fruit and the male flowers produce
pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...
. Many North and Central American species are visited by specialist
bee Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyly, monophyletic lineage within the ...
pollinator A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains. Insects are the maj ...
s, but other insects with more general feeding habits, such as honey bees, also visit. There is debate about the taxonomy of the genus, as the number of accepted species varies from 13 to 30. The five domesticated species are '' Cucurbita argyrosperma'', '' C. ficifolia'', '' C. maxima'', '' C. moschata'', and '' C. pepo''. All of these can be treated as winter squash because the full-grown fruits can be stored for months; however, ''C. pepo'' includes some cultivars that are better used only as summer squash. The fruits of the genus ''Cucurbita'' are good sources of
nutrient A nutrient is a substance used by an organism to survive, grow, and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi, and protists. Nutrients can be incorporated into cells for metabolic purposes or excret ...
s, such as vitamin A and vitamin C, among other nutrients according to species. The fruits have many culinary uses including pumpkin pie, biscuits, bread, desserts, puddings, beverages, and soups. Although botanical fruits, ''Cucurbita'' gourds such as squash are typically cooked and eaten as vegetables. Pumpkins see more varied use, and are eaten both as vegetables and as desserts such as pumpkin pie.


Description

''Cucurbita'' species fall into two main groups. The first group are annual or short-lived perennial vines and are mesophytic, i.e. they require a more or less continuous water supply. The second group are perennials growing in arid zones and so are xerophytic, tolerating dry conditions. Cultivated ''Cucurbita'' species were derived from the first group. Growing in height or length, the plant stem produces tendrils to help it climb adjacent plants and structures or extend along the ground. Most species do not readily root from the nodes; a notable exception is ''C. ficifolia'', and the four other cultivated mesophytes do this to a lesser extent. The vine of the perennial ''Cucurbita'' can become semiwoody if left to grow. There is wide variation in size, shape, and color among ''Cucurbita'' fruits, and even within a single species. ''C. ficifolia'' is an exception, being highly uniform in appearance. The morphological variation in the species ''C. pepo'' and ''C. maxima'' is so vast that its various
subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
and cultivars have been misidentified as totally separate species. The typical cultivated ''Cucurbita'' species has five-lobed or palmately divided leaves with long petioles, with the leaves alternately arranged on the stem. The stems in some species are angular. All of the above-ground parts may be hairy with various types of trichomes, which are often hardened and sharp. Spring-like tendrils grow from each node and are branching in some species. ''C. argyrosperma'' has ovate-cordate (egg-shaped to heart-shaped) leaves. The shape of ''C. pepo'' leaves varies widely. ''C. moschata'' plants can have light or dense pubescence. ''C. ficifolia'' leaves are slightly angular and have light pubescence. The leaves of all four of these species may or may not have white spots. The species are
monoecious Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system alongside gynomonoecy, andromonoecy and trimonoecy. Monoecy is conne ...
, with unisexual male ( staminate) and female (
pistil Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ''pistils'' ...
late) flowers on a single plant and these grow singly, appearing from the
leaf axils A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, ste ...
. Flowers have five fused yellow to orange petals (the
corolla Corolla may refer to: *Corolla (botany), the petals of a flower, considered as a unit *Toyota Corolla, an automobile model name * Corolla (headgear), an ancient headdress in the form of a circlet or crown * ''Corolla'' (gastropod), a genus of moll ...
) and a green bell-shaped
calyx Calyx or calyce (plural "calyces"), from the Latin ''calix'' which itself comes from the Ancient Greek ''κάλυξ'' (''kálux'') meaning "husk" or "pod", may refer to: Biology * Calyx (anatomy), collective name for several cup-like structures ...
. Male flowers in Cucurbitaceae generally have five stamens, but in ''Cucurbita'' there are only three, and their
anther The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filam ...
s are joined together so that there appears to be one. Female flowers have thick
pedicels In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as ''pedicellate''. Description Pedicel refers to a structure connecting a single flower to its inflorescence. In the absenc ...
, and an
inferior ovary In the flowering plants, an ovary is a part of the female reproductive organ of the flower or gynoecium. Specifically, it is the part of the pistil which holds the ovule(s) and is located above or below or at the point of connection with the bas ...
with 3–5 stigmas that each have two lobes. The female flowers of ''C. argyrosperma'' and ''C. ficifolia'' have larger corollas than the male flowers. Female flowers of ''C. pepo'' have a small calyx, but the calyx of ''C. moschata'' male flowers is comparatively short. ''Cucurbita'' fruits are large and fleshy. Botanists classify the ''Cucurbita'' fruit as a
pepo PEPO Lappeenranta (abbreviated PEPO) is a football club from Lappeenranta in Finland. The club was formed in 1958 and their home ground is at the Kimpinen Sports Centre. The men's first team currently plays in the Ykkönen (Second Division). ...
, which is a special type of
berry A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, raspb ...
derived from an inferior ovary, with a thick outer wall or rind with hypanthium tissue forming an exocarp around the ovary, and a fleshy interior composed of mesocarp and endocarp. The term "pepo" is used primarily for Cucurbitaceae fruits, where this fruit type is common, but the fruits of ''
Passiflora ''Passiflora'', known also as the passion flowers or passion vines, is a genus of about 550 species of flowering plants, the type genus of the family Passifloraceae. They are mostly tendril-bearing vines, with some being shrubs or trees. They ...
'' and '' Carica'' are sometimes also pepos. The seeds, which are attached to the ovary wall (parietal placentation) and not to the center, are large and fairly flat with a large embryo that consists almost entirely of two cotyledons. Fruit size varies considerably: wild fruit specimens can be as small as and some domesticated specimens can weigh well over . The current world record was set in 2014 by Beni Meier of
Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...
with a pumpkin.


Taxonomy

''Cucurbita'' was formally described in a way that meets the requirements of modern
botanical nomenclature Botanical nomenclature is the formal, scientific naming of plants. It is related to, but distinct from Alpha taxonomy, taxonomy. Plant taxonomy is concerned with grouping and classifying plants; botanical nomenclature then provides names for the ...
by Linnaeus in his '' Genera Plantarum'', the fifth edition of 1754 in conjunction with the 1753 first edition of ''
Species Plantarum ' (Latin for "The Species of Plants") is a book by Carl Linnaeus, originally published in 1753, which lists every species of plant known at the time, classified into genera. It is the first work to consistently apply binomial names and was the ...
''. ''Cucurbita pepo'' is the type species of the genus. Linnaeus initially included the species ''C. pepo'', ''C. verrucosa'' and ''C. melopepo'' (both now included in ''C. pepo''), as well as ''C. citrullus'' (watermelon, now ''
Citrullus lanatus Watermelon (''Citrullus lanatus'') is a flowering plant species of the Cucurbitaceae family and the name of its edible fruit. A scrambling and trailing vine-like plant, it is a highly cultivated fruit worldwide, with more than 1,000 varieti ...
'') and ''C. lagenaria'' (now '' Lagenaria siceraria'') (both are not ''Cucurbita'' but are in the family Cucurbitaceae. The ''Cucurbita digitata'', ''C. foetidissima'', ''C. galeotti'', and ''C. pedatifolia'' species groups are
xerophytes A xerophyte (from Greek ξηρός ''xeros'' 'dry' + φυτόν ''phuton'' 'plant') is a species of plant that has adaptations to survive in an environment with little liquid water, such as a desert such as the Sahara or places in the Alps or the ...
, arid zone perennials with storage roots; the remainder, including the five domesticated species, are all mesophytic annuals or short-life perennials with no storage roots. The five domesticated species are mostly isolated from each other by sterility barriers and have different physiological characteristics. Some cross pollinations can occur: ''C. pepo'' with ''C. argyrosperma'' and ''C. moschata''; and ''C. maxima'' with ''C. moschata''. Cross pollination does occur readily within the family Cucurbitaceae. The buffalo gourd (''C. foetidissima'') has been used as an intermediary, as it can be crossed with all the common ''Cucurbita''. Various
taxonomic Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...
treatments have been proposed for ''Cucurbita'', ranging from 13 to 30 species. In 1990, ''Cucurbita'' expert Michael Nee classified them into the following oft-cited 13 species groups (27 species total), listed by group and alphabetically, with geographic origin: * '' C. argyrosperma'' (
synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...
''C. mixta'') – cushaw pumpkin; origin: Mexico ** '' C. kellyana'', origin: Pacific coast of western Mexico ** '' C. palmeri'', origin: Pacific coast of northwestern Mexico ** '' C. sororia'', origin: Pacific coast Mexico to Nicaragua, northeastern Mexico * '' C. digitata'' – fingerleaf gourd; origin: southwestern United States (USA), northwestern Mexico ** '' C. californica'' ** '' C. cordata'' ** '' C. cylindrata'' ** '' C. palmata'' * '' C. ecuadorensis'', origin: Ecuador's Pacific coast * '' C. ficifolia'' – figleaf gourd, chilacayote, alcayota; origin: Mexico, Panama, northern Chile and Argentina * '' C. foetidissima'' – stinking gourd, buffalo gourd; origin: Mexico ** '' C. scabridifolia'', likely a natural hybrid of ''C. foetidissima'' and ''C. pedatifolia'' * '' C. galeottii'', little known; origin: Oaxaca, Mexico * '' C. lundelliana'', origin: Mexico, Guatemala, Belize * '' C. maxima'' – winter squash, pumpkin; origin: Argentina, Bolivia, Ecuador ** '' C. andreana'', origin – Argentina * '' C. moschata'' – butternut squash, 'Dickinson' pumpkin, golden cushaw; origin: Bolivia, Colombia, Ecuador, Mexico, Panama, Puerto Rico, Venezuela * '' C. okeechobeensis'', origin: Florida ** '' C. martinezii'', origin: Mexican Gulf Coast and foothills * '' C. pedatifolia'', origin:
Querétaro Querétaro (), officially the Free and Sovereign State of Querétaro ( es, Estado Libre y Soberano de Querétaro, links=no; Otomi language, Otomi: ''Hyodi Ndämxei''), is one of the Political divisions of Mexico, 32 federal entities of Mexico. I ...
, Mexico ** '' C. moorei'' * '' C. pepo'' – field pumpkin, summer squash, zucchini, vegetable marrow, courgette, acorn squash; origin: Mexico, USA ** '' C. fraterna'', origin: Tamaulipas and
Nuevo León Nuevo León () is a state in the northeast region of Mexico. The state was named after the New Kingdom of León, an administrative territory from the Viceroyalty of New Spain, itself was named after the historic Spanish Kingdom of León. With a ...
, Mexico ** '' C. texana'', origin: Texas, USA * '' C. radicans'' – calabacilla, calabaza de coyote; origin: Central Mexico ** '' C. gracilior'' The taxonomy by Nee closely matches the species groupings reported in a pair of studies by a botanical team led by Rhodes and Bemis in 1968 and 1970 based on statistical groupings of several phenotypic traits of 21 species. Seeds for studying additional species members were not available. Sixteen of the 21 species were grouped into five clusters with the remaining five being classified separately: * ''C. digitata'', ''C. palmata'', ''C. californica'', ''C. cylindrata'', ''C. cordata'' * ''C. martinezii'', ''C. okeechobeensis'', ''C. lundelliana'' * ''C. sororia'', ''C. gracilior'', ''C. palmeri''; ''C. argyrosperma'' (reported as ''C. mixta'') was considered close to the three previous species * ''C. maxima'', ''C. andreana'' * ''C. pepo'', ''C. texana'' * ''C. moschata'', ''C. ficifolia'', ''C. pedatifolia'', ''C. foetidissima'', and ''C. ecuadorensis'' were placed in their own separate species groups as they were not considered significantly close to any of the other species studied.


Phylogeny

The full phylogeny of this genus is unknown, and research was ongoing in 2014. The following cladogram of ''Cucurbita'' phylogeny is based upon a 2002 study of
mitochondrial DNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial D ...
by Sanjur and colleagues.


Reproductive biology

All species of ''Cucurbita'' have 20 pairs of chromosomes. Many North and Central American species are visited by specialist
pollinator A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains. Insects are the maj ...
s in the apid tribe
Eucerini The Eucerini (often called long-horned bees) are the most diverse tribe in the family Apidae, with over 32 genera worldwide that were previously classified as members of the family Anthophoridae. All species are solitary, though many nest in lar ...
, especially the genera '' Peponapis'' and ''
Xenoglossa ''Xenoglossa'' is a genus of large squash bees in the family Apidae. There are about 11 described species in ''Xenoglossa''. Species These 11 species belong to the genus ''Xenoglossa'': * ''Xenoglossa angustior'' Cockerell, 1899 * ''Xenoglossa d ...
'', and these
squash bee The name squash bee, also squash and gourd bee, is applied to two related genera of bees in the tribe Eucerini; '' Peponapis'' and ''Xenoglossa''. Both genera are oligoleges (pollen specialists) on the plant genus ''Cucurbita'' and closely relate ...
s can be crucial to the flowers producing fruit after pollination. When there is more pollen applied to the stigma, more seeds are produced in the fruits and the fruits are larger with greater likelihood of maturation, an effect called xenia. Competitively grown specimens are therefore often hand-pollinated to maximize the number of seeds in the fruit, which increases the fruit size; this pollination requires skilled technique. Seedlessness is known to occur in certain cultivars of ''C. pepo''. The most critical factors in flowering and fruit set are physiological, having to do with the age of the plant and whether it already has developing fruit. The
plant hormone Plant hormone (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, from embryogenesis, the regulation of organ size, pa ...
s
ethylene Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon-carbon double bonds). Ethylene i ...
and
auxin Auxins (plural of auxin ) are a class of plant hormones (or plant-growth regulators) with some morphogen-like characteristics. Auxins play a cardinal role in coordination of many growth and behavioral processes in plant life cycles and are essenti ...
are key in fruit set and development. Ethylene promotes the production of female flowers. When a plant already has a fruit developing, subsequent female flowers on the plant are less likely to mature, a phenomenon called "first-fruit dominance", and male flowers are more frequent, an effect that appears due to reduced natural ethylene production within the plant stem. Ethephon, a plant growth regulator product that is converted to ethylene after metabolism by the plant, can be used to increase fruit and seed production. The plant hormone gibberellin, produced in the stamens, is essential for the development of all parts of the male flowers. The development of female flowers is not yet understood. Gibberellin is also involved in other developmental processes of plants such as seed and stem growth.


Germination and seedling growth

Seeds with maximum
germination Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, fer ...
potential develop (in ''C. moschata'') by 45 days after
anthesis Anthesis is the period during which a flower is fully open and functional. It may also refer to the onset of that period. The onset of anthesis is spectacular in some species. In ''Banksia'' species, for example, anthesis involves the extension ...
, and seed weight reaches its maximum 70 days after anthesis. Some varieties of ''C. pepo'' germinate best with eight hours of sunlight daily and a planting depth of . Seeds planted deeper than are not likely to germinate. In ''C. foetidissima'', a weedy species, plants younger than 19 days old are not able to sprout from the roots after removing the shoots. In a seed batch with 90 percent germination rate, over 90 percent of the plants had sprouted after 29 days from planting. Experiments have shown that when more pollen is applied to the stigma, as well as the fruit containing more seeds and being larger (the xenia effect mentioned above), the germination of the seeds is also faster and more likely, and the seedlings are larger. Various combinations of mineral nutrients and light have a significant effect during the various stages of plant growth. These effects vary significantly between the different species of ''Cucurbita''. A type of stored phosphorus called phytate forms in seed tissues as spherical crystalline intrusions in protein bodies called globoids. Along with other nutrients, phytate is used completely during seedling growth. Heavy metal contamination, including cadmium, has a significant negative impact on plant growth. ''Cucurbita'' plants grown in the spring tend to grow larger than those grown in the autumn.


Distribution and habitat

Archaeological investigations have found evidence of domestication of Cucurbita going back over 8,000 years from the very southern parts of Canada down to Argentina and Chile. Centers of domestication stretch from the Mississippi River watershed and Texas down through Mexico and Central America to northern and western South America. Of the 27 species that Nee delineates, five are domesticated. Four of them, ''C. argyrosperma'', ''C. ficifolia'', ''C. moschata'', and ''C. pepo'', originated and were domesticated in Mesoamerica; for the fifth, ''C. maxima'', these events occurred in South America. Within ''C. pepo'', the pumpkins, the scallops, and possibly the crooknecks are ancient and were domesticated at different times and places. The domesticated forms of ''C. pepo'' have larger fruits than non-domesticated forms and seeds that are bigger but fewer in number. In a 1989 study on the origins and development of ''C. pepo'', botanist Harry Paris suggested that the original wild specimen had a small round fruit and that the modern pumpkin is its direct descendant. He suggested that the crookneck, ornamental gourd, and scallop are early variants and that the acorn is a cross between the scallop and the pumpkin. ''C. argyrosperma'' is not as widespread as the other species. The wild form ''C. a.'' subsp. ''sororia'' is found from Mexico to Nicaragua, and cultivated forms are used in a somewhat wider area stretching from Panama to the southeastern United States. It was probably bred for its seeds, which are large and high in oil and protein, but its flesh is of poorer quality than that of ''C. moschata'' and ''C. pepo''. It is grown in a wide altitudinal range: from sea level to as high as in dry areas, usually with the use of irrigation, or in areas with a defined rainy season, where seeds are sown in May and June. ''C. ficifolia'' and ''C. moschata'' were originally thought to be Asiatic in origin, but this has been disproven. The origin of ''C. ficifolia'' is Latin America, most likely southern Mexico, Central America, or the Andes. It grows at elevations ranging from in areas with heavy rainfall. It does not hybridize well with the other cultivated species as it has significantly different enzymes and chromosomes. ''C. maxima'' originated in South America over 4,000 years ago, probably in Argentina and Uruguay. The plants are sensitive to
frost Frost is a thin layer of ice on a solid surface, which forms from water vapor in an above-freezing atmosphere coming in contact with a solid surface whose temperature is below freezing, and resulting in a phase change from water vapor (a gas) ...
, and they prefer both bright sunlight and soil with a pH of 6.0 to 7.0. ''C. maxima'' did not start to spread into North America until after the arrival of Columbus. Varieties were in use by native peoples of the United States by the 16th century. Types of ''C. maxima'' include ''triloba'', ''zapallito'', ''zipinka'', Banana, Delicious, Hubbard, Marrow (''C. maxima'' Marrow), Show, and Turban. ''C. moschata'' is native to Latin America, but the precise location of origin is uncertain. It has been present in Mexico, Belize, Guatemala, and Peru for 4,000–6,000 years and has spread to Bolivia, Ecuador, Panama, Puerto Rico, and Venezuela. This species is closely related to ''C. argyrosperma''. A variety known as the Seminole Pumpkin has been cultivated in Florida since before the arrival of Columbus. Its leaves are wide. It generally grows at low elevations in hot climates with heavy rainfall, but some varieties have been found above . Groups of ''C. moschata'' include Cheese, Crookneck (''C. moschata''), and Bell. ''C. pepo'' is one of the oldest, if not the oldest, domesticated species with the oldest known locations being Oaxaca, Mexico, 8,000–10,000 years ago, and Ocampo, Tamaulipas, Mexico, about 7,000 years ago. It is known to have appeared in Missouri, United States, at least 4,000 years ago. Debates about the origin of ''C. pepo'' have been on-going since at least 1857. There have traditionally been two opposing theories about its origin: 1) that it is a direct descendant of ''C. texana'' and 2) that ''C. texana'' is merely feral ''C. pepo''. A more recent theory by botanist Thomas Andres in 1987 is that descendants of ''C. fraterna'' hybridized with ''C. texana'', resulting in two distinct domestication events in two different areas: one in Mexico and one in the eastern United States, with ''C. fraterna'' and ''C. texana'', respectively, as the ancestral species. ''C. pepo'' may have appeared in the Old World before moving from Mexico into South America. It is found from sea level to slightly above . Leaves have 3–5 lobes and are wide. All the subspecies, varieties, and cultivars are interfertile. In 1986 Paris proposed a revised taxonomy of the edible cultivated ''C. pepo'' based primarily on the shape of the fruit, with eight groups . All but a few ''C. pepo'' cultivars can be included in these groups. There is one non-edible cultivated variety: ''C. pepo'' var. ''ovifera''.


History and domestication

The ancestral species of the genus ''Cucurbita'' were present in the Americas before the arrival of humans, and are native to the
Americas The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World. Along with th ...
. The likely center of origin is southern Mexico, spreading south through what is now known as Mesoamerica, on into South America, and north to what is now the southwestern United States. Evolutionarily speaking, the genus is relatively recent in origin, dating back only to the Holocene, whereas the family Cucurbitaceae, in the shape of seeds similar to '' Bryonia'', dates to the Paleocene. Recent genomic studies support the idea that the ''Cucurbita'' genus underwent a whole-genome duplication event, increasing their number of chromosomes and accelerating the rate at which their genomes evolve compared to other cucurbits. No species within the genus is entirely genetically isolated. ''C. moschata'' can intercross with all the others, though the hybrid offspring may not themselves be fertile unless they become polyploid. The genus was part of the culture of almost every native peoples group from southern South America to southern Canada. Modern-day cultivated ''Cucurbita'' are not found in the wild. Genetic studies of the mitochondrial gene '' nad1'' show there were at least six independent domestication events of ''Cucurbita'' separating domestic species from their wild ancestors. Species native to North America include '' C. digitata'' (calabazilla), and ''C. foetidissima'' (buffalo gourd), '' C. palmata'' (coyote melon), and ''C. pepo''. Some species, such as ''C. digitata'' and ''C. ficifolia,'' are referred to as ''gourds''. Gourds, also called bottle-gourds, which are used as utensils or vessels, belong to the genus '' Lagenaria'' and are native to Africa. ''Lagenaria'' are in the same family and subfamily as ''Cucurbita'' but in a different tribe. The earliest known evidence of the domestication of ''Cucurbita'' dates back at least 8,000 years ago, predating the domestication of other crops such as maize and
bean A bean is the seed of several plants in the family Fabaceae, which are used as vegetables for human or animal food. They can be cooked in many different ways, including boiling, frying, and baking, and are used in many traditional dishes th ...
s in the region by about 4,000 years. This evidence was found in the Guilá Naquitz cave in Oaxaca, Mexico, during a series of excavations in the 1960s and 1970s, possibly beginning in 1959. Solid evidence of domesticated ''C. pepo'' was found in the Guilá Naquitz cave in the form of increasing rind thickness and larger peduncles in the newer stratification layers of the cave. By c. 8,000 years BP the ''C. pepo'' peduncles found are consistently more than thick. Wild ''Cucurbita'' peduncles are always below this 10 mm barrier. Changes in fruit shape and color indicate that intentional breeding of ''C. pepo'' had occurred by no later than 8,000 years BP. During the same time frame, average rind thickness increased from . Recent genomic studies suggest that '' Cucurbita argyrosperma'' was domesticated in Mexico, in the region that is currently known as the state of
Jalisco Jalisco (, , ; Nahuatl: Xalixco), officially the Free and Sovereign State of Jalisco ( es, Estado Libre y Soberano de Jalisco ; Nahuatl: Tlahtohcayotl Xalixco), is one of the 31 states which, along with Mexico City, comprise the 32 Federal En ...
. Squash was domesticated first, followed by maize and then beans, becoming part of the Three Sisters agricultural system of companion planting. The English word "squash" derives from ''askutasquash'' (a green thing eaten raw), a word from the Narragansett language, which was documented by
Roger Williams Roger Williams (21 September 1603between 27 January and 15 March 1683) was an English-born New England Puritan minister, theologian, and author who founded Providence Plantations, which became the Colony of Rhode Island and Providence Plantation ...
, the founder of Rhode Island, in his 1643 publication '' A Key Into the Language of America''. Similar words for squash exist in related languages of the Algonquian family.


Production

The family Cucurbitaceae has many species used as human food. ''Cucurbita'' species are some of the most important of those, with the various species being prepared and eaten in many ways. Although the stems and skins tend to be more bitter than the flesh, the fruits and
seeds A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosperm pl ...
of cultivated varieties are quite edible and need little or no preparation. The flowers and young leaves and shoot tips can also be consumed. The seeds and fruits of most varieties can be stored for long periods of time, particularly the sweet-tasting winter varieties with their thick, inedible skins. Summer squash have a thin, edible skin. The seeds of both types can be roasted, eaten raw, made into pumpkin seed oil, ground into a flour or meal, or otherwise prepared. Squashes are primarily grown for the fresh food market. The Food and Agriculture Organization of the United Nations (FAO) reported that the ranking of the top five squash-producing countries was stable between 2005 and 2009. Those countries are: China, India, Russia, the United States, and Egypt. By 2012, Iran had moved into the 5th slot, with Egypt falling to 6th. The only additional countries that rank in the top 20 where squashes are native are Cuba, which ranks 14th with 347,082 metric tons, and Argentina, which ranks 17th, with 326,900 metric tons. In addition to being the 4th largest producer of squashes in the world, the United States is the world's largest importer of squashes, importing 271,614 metric tons in 2011, 95 percent of that from Mexico. Within the United States, the states producing the largest amounts are Florida, New York, California, and North Carolina.


Nutrients

As an example of ''Cucurbita'', raw summer squash is 94% water, 3%
carbohydrates In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or may ...
, and 1% protein, with negligible fat content (table). In a 100-gram reference serving, raw squash supplies of food energy and is rich in vitamin C (20% of the Daily Value, DV), moderate in vitamin B6 and
riboflavin Riboflavin, also known as vitamin B2, is a vitamin found in food and sold as a dietary supplement. It is essential to the formation of two major coenzymes, flavin mononucleotide and flavin adenine dinucleotide. These coenzymes are involved in ...
(12–17% DV), but otherwise devoid of appreciable nutrient content (table), although the nutrient content of different ''Curcubita'' species may vary somewhat. Pumpkin seeds contain vitamin E, crude protein, B vitamins and several dietary minerals (see nutrition table at pepita). Also present in pumpkin seeds are unsaturated and
saturated Saturation, saturated, unsaturation or unsaturated may refer to: Chemistry * Saturation, a property of organic compounds referring to carbon-carbon bonds ** Saturated and unsaturated compounds **Degree of unsaturation ** Saturated fat or fatty ac ...
oils,
palmitic Palmitic acid (hexadecanoic acid in IUPAC nomenclature) is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms.Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra. The Li ...
,
oleic Oleic acid is a fatty acid that occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish. In chemical terms, oleic acid is classified as a monounsaturated omega ...
and
linoleic Linoleic acid (LA) is an organic compound with the formula COOH(CH2)7CH=CHCH2CH=CH(CH2)4CH3. Both alkene groups are ''cis''. It is a fatty acid sometimes denoted 18:2 (n-6) or 18:2 ''cis''-9,12. A linoleate is a salt or ester of this acid. L ...
fatty acids, as well as carotenoids.


Toxins

Cucurbitin Cucurbitin is an amino acid and a carboxy pyrrolidine that is found in ''Cucurbita ''Cucurbita'' (Latin for gourd) is a genus of herbaceous fruits in the gourd family, Cucurbitaceae (also known as ''cucurbits'' or ''cucurbi''), native to the ...
is an amino acid and a
carboxy In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic ...
pyrrolidine Pyrrolidine, also known as tetrahydropyrrole, is an organic compound with the molecular formula (CH2)4NH. It is a cyclic secondary amine, also classified as a saturated heterocycle. It is a colourless liquid that is miscible with water and most ...
that is found in raw ''Cucurbita'' seeds. It retards the development of parasitic flukes when administered to infected host mice, although the effect is only seen if administration begins immediately after infection.
Cucurmosin Cucurmosin is a type I ribosome inactivating protein (RIP) found in the sarcocarp (flesh) and seed of ''Cucurbita'' — notably ''Cucurbita moschata'', that is toxic to cancer cells, if the dosage is high enough, by stopping their ribosomes. Cucurm ...
is a
ribosome inactivating protein A ribosome-inactivating protein (RIP) is a protein synthesis inhibitor that acts at the eukaryotic ribosome. This protein family describes a large family of such proteins that work by acting as rRNA N-glycosylase (EC 3.2.2.22). They inactivate 6 ...
found in the flesh and seed of ''Cucurbita'', notably '' Cucurbita moschata''. Cucurmosin is more toxic to cancer cells than healthy cells. Cucurbitacin is a plant steroid present in wild ''Cucurbita'' and in each member of the family ''Cucurbitaceae''. Poisonous to mammals, it is found in quantities sufficient to discourage herbivores. It makes wild ''Cucurbita'' and most ornamental gourds, with the exception of an occasional ''C. fraterna'' and ''C. sororia'', bitter to taste. Ingesting too much cucurbitacin can cause stomach cramps, diarrhea and even collapse. This bitterness is especially prevalent in wild Cucurbita; in parts of Mexico, the flesh of the fruits is rubbed on a woman's breast to wean children. While the process of domestication has largely removed the bitterness from cultivated varieties, there are occasional reports of cucurbitacin causing illness in humans. Cucurbitacin is also used as a lure in insect traps.


Pests and diseases

''Cucurbita'' species are used as food plants by the larvae of some
Lepidoptera Lepidoptera ( ) is an order (biology), order of insects that includes butterfly, butterflies and moths (both are called lepidopterans). About 180,000 species of the Lepidoptera are described, in 126 Family (biology), families and 46 Taxonomic r ...
species, including the cabbage moth (''Mamestra brassicae''), '' Hypercompe indecisa'', and the turnip moth (''Agrotis segetum''). ''Cucurbita'' can be susceptible to the pest ''Bemisia argentifolii'' ( silverleaf whitefly) as well as aphids ('' Aphididae''),
cucumber beetle Cucumber beetle is a common name given to members of two genera of beetles, ''Diabrotica'' and ''Acalymma'', both in the family Chrysomelidae. The adults can be found on cucurbits such as cucumbers and a variety of other plants. Many are no ...
s (''Acalymma vittatum'' and ''
Diabrotica undecimpunctata ''Diabrotica undecimpunctata'', the spotted cucumber beetle or southern corn rootworm, is a species of cucumber beetle that is native to North America. The species can be a major agricultural pest insect in North America. Spotted cucumber beetle ...
howardi''), squash bug (''
Anasa tristis ''Anasa tristis'' is a species of bug in the family Coreidae. It is a major pest of squash and pumpkins, found throughout North America, and is a vector of the cucurbit yellow vine disease bacterium. These bugs can emit an unpleasant odor w ...
''), the
squash vine borer The squash vine borer (''Melittia cucurbitae'') is a diurnal species of sesiid moth. The moth is often mistaken for a bee or wasp because of its movements, and the bright orange hind leg scales. The females typically lay their eggs at the base ...
(''Melittia cucurbitae''), and the two-spotted spidermite ('' Tetranychus urticae''). The squash bug causes major damage to plants because of its very toxic saliva. The
red pumpkin beetle ''Aulacophora foveicollis'', the red pumpkin beetle, is a species of beetle in the family Chrysomelidae. It is a foliar pest of members of the Cucurbitaceae, particularly the pumpkin. It is also a pest of millets in India. Description The adult ...
(''Aulacophora foveicollis'') is a serious pest of cucurbits, especially the pumpkin, which it can defoliate.
Cucurbits The Cucurbitaceae, also called cucurbits or the gourd family, are a plant family consisting of about 965 species in around 95 genera, of which the most important to humans are: *''Cucurbita'' – squash, pumpkin, zucchini, some gourds *''Lagena ...
are susceptible to diseases such as bacterial wilt (''Erwinia tracheiphila''), anthracnose ('' Colletotrichum'' spp.), fusarium wilt ('' Fusarium'' spp.), phytophthora blight ('' Phytophthora'' spp.
water molds Oomycota forms a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms, called oomycetes (). They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction of an oospore is the result ...
), and powdery mildew ('' Erysiphe'' spp.). Defensive responses to viral, fungal, and bacterial leaf pathogens do not involve cucurbitacin. Species in the genus ''Cucurbita'' are susceptible to some types of mosaic virus including:
cucumber mosaic virus ''Cucumber mosaic virus'' (CMV) is a plant pathogenic virus in the family ''Bromoviridae''. This virus has a worldwide distribution and a very wide host range, having the reputation of the widest host range of any known plant virus. It can be tra ...
(CMV), papaya ringspot virus-cucurbit strain (PRSV),
squash mosaic virus ''Squash mosaic virus'' (SqMV) is a mosaic virus disease common in squash plants and other plants, including melons, of the family Cucurbitaceae. It occurs worldwide. It is transmitted primarily by beetles, including the leaf beetle ('' Acalymma ...
(SqMV), tobacco ringspot virus (TRSV),
watermelon mosaic virus ''Watermelon mosaic virus'' (WMV) also known as Marrow mosaic virus (Raychaudhuri and Varma, 1975; Varma, 1988), Melon mosaic virus (Iwaki et al., 1984; Komuro, 1962), and until recently Watermelon mosaic virus type 2 (WMV-2), is a plant pathogen ...
(WMV), and zucchini yellow mosaic virus (ZYMV). PRSV is the only one of these viruses that does not affect all cucurbits. SqMV and CMV are the most common viruses among cucurbits. Symptoms of these viruses show a high degree of similarity, which often results in laboratory investigation being needed to differentiate which one is affecting plants.


Human culture


Culinary uses

Long before European contact, ''Cucurbita'' had been a major food source for the native peoples of the Americas, and the species became an important food for European settlers, including the Pilgrims, even featuring at the first Thanksgiving. Commercially produced pumpkin commonly used in pumpkin pie is most often varieties of ''C. moschata''; Libby's, by far the largest producer of processed pumpkin, uses a proprietary strain of the Dickinson pumpkin variety of ''C. moschata'' for its canned pumpkin. Other foods that can be made using members of this genus include biscuits,
bread Bread is a staple food prepared from a dough of flour (usually wheat) and water, usually by baking. Throughout recorded history and around the world, it has been an important part of many cultures' diet. It is one of the oldest human-made f ...
, cheesecake, desserts, donuts, granola, ice cream, lasagna dishes, pancakes, pudding, pumpkin butter, salads, soups, and stuffing. Squash soup is a dish in African cuisine. The xerophytic species are proving useful in the search for nutritious foods that grow well in arid regions. ''C. ficifolia'' is used to make soft and mildly alcoholic drinks. In India, squashes (''ghiya'') are cooked with seafood such as prawns. In France, marrows (''courges'') are traditionally served as a gratin, sieved and cooked with butter, milk, and egg, and flavored with salt, pepper, and nutmeg, and as soups. In Italy, zucchini and larger squashes are served in a variety of regional dishes, such as ''cocuzze alla puviredda'' cooked with olive oil, salt and herbs from
Apulia it, Pugliese , population_note = , population_blank1_title = , population_blank1 = , demographics_type1 = , demographics1_footnotes = , demographics1_title1 = , demographics1_info1 = , demographic ...
; as ''torta di zucca'' from Liguria, or ''torta di zucca e riso'' from Emilia-Romagna, the squashes being made into a pie filling with butter, ricotta,
parmesan Parmesan ( it, Parmigiano Reggiano; ) is an Italian hard, granular cheese produced from cows’ milk and aged at least 12 months. It is named after two of the areas which produce it, the provinces of Parma and Reggio Emilia (''Parmigiano'' is ...
, egg, and milk; and as a sauce for pasta in dishes like ''spaghetti alle zucchine'' from Sicily. In Japan, squashes such as small ''C. moschata'' pumpkins (''kabocha'') are eaten boiled with sesame sauce, fried as a tempura dish, or made into balls with
sweet potato The sweet potato or sweetpotato (''Ipomoea batatas'') is a dicotyledonous plant that belongs to the Convolvulus, bindweed or morning glory family (biology), family, Convolvulaceae. Its large, starchy, sweet-tasting tuberous roots are used as a r ...
and
Japanese mountain yam ''Dioscorea japonica'', known as East Asian mountain yam, yamaimo, or Japanese mountain yam, is a type of yam (''Dioscorea'') native to Japan (including Ryukyu and Bonin Islands), Korea, China, Taiwan, and Assam. ''Dioscorea japonica'' is used ...
.


Art, music, and literature

Along with maize and beans, squash has been depicted in the art work of the native peoples of the Americas for at least 2,000 years. For example, cucurbits are often represented in Moche ceramics. Though native to the western hemisphere, ''Cucurbita'' began to spread to other parts of the world after Christopher Columbus's arrival in the New World in 1492. Until recently, the earliest known depictions of this genus in Europe was of ''Cucurbita pepo'' in '' De Historia Stirpium Commentarii Insignes'' in 1542 by the German botanist
Leonhart Fuchs Leonhart Fuchs (; 17 January 1501 – 10 May 1566), sometimes spelled Leonhard Fuchs and cited in Latin as ''Leonhartus Fuchsius'', was a German physician and botanist. His chief notability is as the author of a large book about plants and th ...
, but in 1992, two paintings, one of ''C. pepo'' and one of ''C. maxima'', painted between 1515 and 1518, were identified in festoons at Villa Farnesina in Rome. Also, in 2001 depictions of this genus were identified in '' Grandes Heures of Anne of Brittany'' (''Les Grandes Heures d'Anne de Bretagne''), a French devotional book, an
illuminated manuscript An illuminated manuscript is a formally prepared document where the text is often supplemented with flourishes such as borders and miniature illustrations. Often used in the Roman Catholic Church for prayers, liturgical services and psalms, the ...
created between 1503 and 1508. This book contains an illustration known as ''Quegourdes de turquie'', which was identified by cucurbit specialists as ''C. pepo'' subsp. ''texana'' in 2006. In 1952, Stanley Smith Master, using the pen name Edrich Siebert, wrote "The Marrow Song (Oh what a beauty!)" to a tune in time. It became a popular hit in Australia in 1973, and was revived by
the Wurzels The Wurzels are an English Scrumpy and Western band from Somerset, England, best known for their number one hit " The Combine Harvester" and number three hit "I Am a Cider Drinker" in 1976. They are known for using British West Country phrases ...
in Britain on their 2003 album ''Cutler of the West''.
John Greenleaf Whittier John Greenleaf Whittier (December 17, 1807 – September 7, 1892) was an American Quaker poet and advocate of the abolition of slavery in the United States. Frequently listed as one of the fireside poets, he was influenced by the Scottish poet ...
wrote a poem entitled ''The Pumpkin'' in 1850. "The Great Pumpkin" is a fictional holiday figure in the
comic strip A comic strip is a sequence of drawings, often cartoons, arranged in interrelated panels to display brief humor or form a narrative, often serialized, with text in balloons and captions. Traditionally, throughout the 20th and into the 21st ...
'' Peanuts'' by Charles M. Schulz.


Cleansing and personal care uses

''C. foetidissima'' contains a
saponin Saponins (Latin "sapon", soap + "-in", one of), also selectively referred to as triterpene glycosides, are bitter-tasting usually toxic plant-derived organic chemicals that have a foamy quality when agitated in water. They are widely distributed ...
that can be obtained from the fruit and root. This can be used as a soap, shampoo, and bleach. Prolonged contact can cause skin irritation. Pumpkin is also used in cosmetics.


Folk remedies

''Cucurbita'' have been used in various cultures as folk remedies. Pumpkins have been used by Native Americans to treat intestinal worms and urinary ailments. This Native American remedy was adopted by American doctors in the early nineteenth century as an anthelmintic for the expulsion of worms. In southeastern Europe, seeds of ''C. pepo'' were used to treat irritable bladder and benign prostatic hyperplasia. In Germany, pumpkin seed is approved for use by the Commission E, which assesses folk and herbal medicine, for irritated bladder conditions and micturition problems of prostatic hyperplasia stages 1 and 2, although the monograph published in 1985 noted a lack of pharmacological studies that could substantiate empirically found clinical activity. The
FDA The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food s ...
in the United States, on the other hand, banned the sale of all such non-prescription drugs for the treatment of prostate enlargement in 1990. In China, ''C. moschata'' seeds were also used in traditional Chinese medicine for the treatment of the parasitic disease
schistosomiasis Schistosomiasis, also known as snail fever, bilharzia, and Katayama fever, is a disease caused by parasitic flatworms called schistosomes. The urinary tract or the intestines may be infected. Symptoms include abdominal pain, diarrhea, bloody s ...
and for the expulsion of tape worms. In Mexico, herbalists use ''C. ficifolia'' in the belief that it reduces blood sugar levels.


Festivals

''Cucurbita'' fruits including pumpkins and marrows are celebrated in festivals in countries such as Argentina, Austria, Bolivia, Britain, Canada, Croatia, France, Germany, India, Italy, Japan, Peru, Portugal, Spain, Switzerland, and the United States. Argentina holds an annual nationwide pumpkin festival ''Fiesta Nacional del Zapallo'' ("Squashes and Pumpkins National Festival"), in Ceres, Santa Fe, on the last day of which a ''Reina Nacional del Zapallo'' ("National Queen of the Pumpkin") is chosen. In Portugal the ''Festival da Abóbora de Lourinhã e Atalaia'' ("Squashes and Pumpkins Festival in
Lourinhã Lourinhã () is a municipality in the District of Lisbon, in the Oeste Subregion of Portugal. The population in 2011 was 25,735, in an area of 147.17 km². The seat of the municipality is the town of Lourinhã, with a population of 8,800 inhab ...
and Atalaia") is held in Lourinhã city, called the ''Capital Nacional da Abóbora'' (the "National Capital of Squashes and Pumpkins").
Ludwigsburg, Germany Ludwigsburg (; Swabian: ''Ludisburg'') is a city in Baden-Württemberg, Germany, about north of Stuttgart city centre, near the river Neckar. It is the largest and primary city of the Ludwigsburg district with about 88,000 inhabitants. It is ...
annually hosts the world's largest pumpkin festival. In Britain a giant marrow (zucchini) weighing was displayed in the Harrogate Autumn Flower Show in 2012. In the US, pumpkin chucking is practiced competitively, with machines such as trebuchets and air cannons designed to throw intact pumpkins as far as possible. The Keene Pumpkin Fest is held annually in New Hampshire; in 2013 it held the world record for the most jack-o-lanterns lit in one place, 30,581 on October 19, 2013.
Halloween Halloween or Hallowe'en (less commonly known as Allhalloween, All Hallows' Eve, or All Saints' Eve) is a celebration observed in many countries on 31 October, the eve of the Western Christian feast of All Saints' Day. It begins the observanc ...
is widely celebrated with jack-o-lanterns made of large orange pumpkins carved with ghoulish faces and illuminated from inside with candles. The pumpkins used for jack-o-lanterns are ''C. pepo'', not to be confused with the ones typically used for pumpkin pie in the United States, which are ''C. moschata''. Kew Gardens marked Halloween in 2013 with a display of pumpkins, including a towering pyramid made of many varieties of squash, in the Waterlily House during its "IncrEdibles" festival.


See also

* List of gourds and squashes in the genus ''Cucurbita'' *
List of squash and pumpkin dishes This is a list of notable squash and pumpkin dishes that are prepared using squash and pumpkin as a primary ingredient. Pumpkin is a squash cultivar. Squash and pumpkin dishes and foods * ''Hobak-juk'' – a Korean variety of '' juk'' (porridg ...


Notes


References


External links

* * * {{Authority control Cucurbitaceae genera Squashes and pumpkins Early agriculture in Mesoamerica Crops originating from indigenous Americans Native American cuisine