Cucurbita ficifolia

Cucúrbita ficifólia, popularmente conocida como chilacayote (en México, Guatemala y El Salvador), chiverre (en Costa Rica), alcayota (Chile y Argentina ) y calabaza de cabello de ángel o cidra (en España) es una especie trepadora de fruto comestible de la familia de las cucurbitáceas. Es la especie más importante de calabazas en las regiones de grandes altitudes del Neotrópico, incluyendo los siete países de Sudamérica en los que se despliegan los Andes. Además de su extensiva área de cultivo tradicional, esta especie se ha dispersado en las últimas pocas centurias a lo largo de todas las regiones tropicales y subtropicales de grandes altitudes del mundo y en zonas templadas suaves. Su popularidad parece deberse a la facilidad de su cultivo en regiones frescas bajo condiciones extremas de sequía o de humedad. A bajas alturas se la puede cultivar como pie de injerto de otras enredaderas cucurbitáceas como melones y pepinos. Los frutos poseen similares cualidades nutricionales o sabor que las demás especies cultivadas de Cucurbita, pero poseen una longevidad muy larga debida a las propiedades de su cáscara.

Cucurbita ficifolia

Fruto y hojas.
Taxonomía
Reino: Plantae
División: Magnoliophyta
Clase: Magnoliopsida
Orden: Cucurbitales
Familia: Cucurbitáceas
Subfamilia: Cucurbitoideae
Tribu: Cucurbiteae
Género: Cucurbita
Especie: C. ficifolia
Bouché, 1837
Sinonimia
Tallo de melón (Cucumis melo) injertado sobre un pie de C. ficifolia.
Chilacayote en dulce
Chilacayote en dulce
Chilacayote en dulce
Harmelon phygolistkovy Cucurbita ficifolia - frutas
Harmelon phygolistkovy Cucurbita ficifolia - frutas

Los usos varían en diferentes regiones, pero principalmente es utilizada como alimento en el mismo lugar donde se la cultiva, en sistemas agrícolas pequeños y sustentables. Si no, los frutos son vendidos en mercados locales. Usos más comerciales se encuentran en México, Costa Rica, Colombia, Ecuador y Argentina, donde es utilizada para confites y dulces y también es cocido en platos tradicionales no dulces.

El registro arqueológico muestra que fue extensivamente utilizada y comercializada en tiempos pre-incaicos en el norte de Perú. La variación morfológica de la especie, si bien comparativamente pequeña para una Cucurbita domesticada, es más amplia en la región de Perú a Colombia, lo que indica que su domesticación potencial fue en esta área. El ancestro silvestre es desconocido. (Introducción tomada de TC. Andres 2006[1]).

En el mismo género se encuentran cuatro especies con variedades cultivadas (Cucurbita pepo, C. maxima, C. moschata, C. argyrosperma), pero C. ficifolia está alejada evolutivamente de estas, su pulpa no posee el característico "sabor a zapallo" (=sabor a calabaza) de las demás, y difiere en el hábitat al que está adaptada, y en otros caracteres morfológicos y moleculares. No híbrida con ninguna otra especie cultivada ni variedad silvestre.[cita 1] Como en las demás cucurbitáceas, las partes herbáceas jóvenes y flores también pueden ser aprovechadas como verdura, sus frutos inmaduros pueden consumirse en forma similar a un calabacín o un zapallito, y sus semillas también son comestibles.

Clasificación y descripción

Ha sido descrita en TC. Andrés (1990),[2] en la monografía de cucurbitáceas latinoamericanas de importancia económica de R. Lira Saade (1995)[3] y e TC. Andrés (2006).[1]

Plantas rastreras o trepadoras, monoicas , anuales aunque persistentes por un cierto periodo dando la impresión de ser perennes de vida corta, sin raíces engrosadas de reserva; resistentes a bajas temperaturas, pero no a heladas severas; vellosas a suavemente pubescentes, con algunos aguijones cortos y punzantes esparcidos en las partes vegetativas. Tallos vigorosos, ligeramente angulosos. Hojas con peciolos de 5-25 cm; ovado cordados a suborbicular-cordados, con o sin manchas blancas en el haz, 3-5 lobuladas, con lóbulos redondeados u obtusos, apiculados, el central más grande que los laterales, márgenes denticulados 3-4 zarcillos ramificados. Flores pentámeras, solitarias, axilares. Flores masculinas largamente pediceladas; cáliz campanulado, de 5-10 mm de largo y casi igual de ancho, sépalos lineares, de 5-15 x 1-2 mm; corola tubular- campanulada algo ensanchada hacia la base, de 6-12 cm de largo, amarilla a anaranjada pálida, 3 estambres. Flores femeninas con pedúnculos robustos, de 3-5 cm de largo; ovario ovoide a elíptico, multilocular, sépalos ocasionalmente foliáceos y corola algo más grande que en las masculinas; estilo engrosado, 3 estigmas lobados. Frutos de (15.0-)25.0-50.0 cm largo, globosos a ovoide-elípticos de color verde claro u oscuro, con o sin rayas o franjas longitudinales blancas hacia el ápice, diminutamente manchados de blanco o verde y blancos o crema, pulpa blanca, dulce, cáscara rígida, persistente, sin costillas. Semillas ovado-elípticas comprimidas de 15 a 12 mm de color pardo oscuras o negras. Algunos frutos de tamaño mediano pueden contener más de 500 semillas. Raíces primarias y adventicias fibrosas.[4][5][6]

C. ficifolia es en su hábito una típica[cita 2] Cucurbita anual[cita 3]: trepadora, enredadera por zarcillos, rastrera (enraiza en los nudos en contacto con la tierra), sensible a heladas, de duración anual en zonas templadas, zonas donde al final de la primera temporada formó frutos maduros preparados para sobrevivir el invierno en forma de semilla, sin órganos de almacenamiento en el adulto. En las grandes alturas montañosas de clima fresco y sin heladas donde suele ser cultivada, su longevidad es de varios años, longevidad que no llegan a tener las demás Cucurbita cultivadas debido a que el tiempo frío, aunque no hiele, resiente sus tejidos y las envejece rápidamente.[cita 3] Donde su longevidad es de más de una temporada, luego de su primera temporada cobra características semileñosas. No hay razas ni cultivares nombrados,[cita 4] pero sí hay formas "de día corto" y "de día largo" (o mejor dicho insensibles a la duración del día), es decir que la primera fallará en florecer al norte o al sur de la zona tórrida.[cita 5]

Siendo en su morfología una típica Cucurbita cultivada,[cita 2] a diferencia de las otras 4 es relativamente homogénea, en particular el fruto del que se esperaría variabilidad debida a las presiones de selección, es inesperadamente homogéneo en forma, cáscara y pulpa, y relativamente fácil de distinguir de los frutos de las demás especies.[cita 6] El color exterior puede tener básicamente 3 patrones de color: blanco; verde oscuro (a veces con 10 bandas longitudinales blancas que se extienden del extremo proximal al extremo distal); o un variegado de estos dos colores reticulados, que puede también tener bandas blancas[cita 4]. El patrón es a veces similar y confundido con el patrón de colores de la sandía (Citrullus lanatus).[cita 7] Forma y color exterior del fruto también puede ser confundido con algunas razas de C. maxima[cita 7] (o al menos con la subespecie silvestre, C. maxima subsp. andreana. El tamaño del fruto es de 15 a 50 cm de largo, los vendedores al costado de la ruta comentan que se han visto frutos de 100 cm de largo.[cita 7] No se han asociado estas diferencias en el color del fruto con diferencias en la composición de la pulpa.[cita 4] La pulpa seca, fibrosa, de color claro, como algunas formas de C. argyrosperma.[cita 7]

  • Cucurbita ficifolia
  • Flor femenina.
    Flor femenina.
  • Fruto.
    Fruto.
  • Hoja
    Hoja

Además de la longevidad y el fruto, otros dos caracteres suelen ser mencionados como diferenciales del resto de las Cucurbita cultivadas: la forma de su hoja "como la de la higuera" (Ficus carica) y las semillas negras; los dos necesitan algunas aclaraciones.[cita 8]

Hojas de Cucurbita ficifolia.

Las hojas como en las demás Cucurbita: con pecíolo, de nerviación pentapalmada (o puede verse como hepta-palmada?), de gran tamaño. En esta especie son color verde oscuro, de dorso pubescente, similares a la hoja de la higuera, de ello deriva su nombre científico (ficifolia, "de hojas de higuera" en latín). Pero otras especies de Cucurbita pueden presentar hojas como de higuera: la silvestre C. lundelliana, la feral C. ecuadorensis, y las cultivadas C. moschata y C. pepo.[cita 9] Se ha informado una forma de hojas "tipo C. moschata" que no ha tenido todavía confirmación visual por parte de un taxónomo.[cita 1]

La mayoría de las formas son de semillas negras, pero no todas las semillas de C. ficifolia lo son, algunas son marrón oscuro (dark brown) y otras de un color buff-colored más parecido al de otras especies de Cucurbita.[cita 10] De las demás Cucurbita, algunas razas de C. moschata del norte de Sudamérica son de semillas marrones.[cita 10] No hay diferencias regionales ni razas asociadas al color de semilla.[cita 4]

La especie también puede diferenciarse por la forma de la semilla (ver en[cita 11]), por la presencia de tricomas en los filamentos de sus estambres (ver en[cita 12]), en la presencia de tricomas setáceos en el tallo similares a los de C. maxima[cita 7], y en el pedúnculo duro, de ángulos redondeados, y ligeramente extendido sobre el fruto en la unión a él, como en C. ecuadorensis y algunas razas de C. moschata.[cita 7]

Número cromosómico

20 pares de cromosomas como en Cucurbita.[2][25]

Origen, cultivo y distribución

Algunos autores han propuesto que el origen de C. ficifolia es centroamericano o sur-mexicano-centroamericano, mientras que otros sugieren que se ubica en América del Sur, más específicamente en la zona de Los Andes. El área de distribución de esta especie abarca las zonas medias o altas de prácticamente todas las cordilleras o cadenas montañosas de Latinoamérica, desde el norte de México hasta Chile y el noroeste de Argentina, sin embargo, como en el caso de su origen, el centro de domesticación y diversificación, aún representa un enigma a resolver, sin embargo, los restos arqueológicos encontrados en Perú, pudiesen inclinar la balanza hacia esta zona. Esta especie originaria de América Latina se difundió como cultivo tanto dentro como fuera del continente americano, en Europa, en África, en Asia, India y finalmente en Oceanía[26][cita 13], los primeros frutos de C. ficifolia en llegar a Europa aparentemente tomaron una ruta desde Sudamérica a la costa de Malabar de la India a lo largo de la muy recorrida ruta comercial portuguesa y holandesa en los siglos XVI y XVII, de donde llegaron finalmente a Europa.[cita 13]

Se ignora con exactitud su región de origen; distintas líneas de evidencia apuntan a México o a la cordillera de los Andes, pero no se ha podido corroborar ninguna hipótesis.[cita 14] La evidencia lingüística favorecería un origen mexicano, ya que el nombre empleado casi universalmente pareciera ser de origen náhuatl; sin embargo, los restos arqueológicos más antiguos conservados provienen del Perú.[cita 14] Aparentemente fue bien conocida a lo largo de la costa peruana y se hipotetizó que luego de su establecimiento puede haber sido abandonada en favor de las especies de zapallos, conservándose su cultivo solo en las zonas altas montañosas.[cita 14] Se desconoce la variedad silvestre de la que se haya originado, y las hipótesis apuntan a una especie aún desconocida, posiblemente nativa de la región oriental de la cordillera andina.[cita 14]

Hoy se cultiva desde Chile y el noroeste de Argentina hasta el sur de los Estados Unidos; pero solo en las regiones montañosas frías donde no se dan bien otras especies de cucurbitáceas. La India, el Japón y las Filipinas, que hoy son importantes productores.

Es la menos intensamente cultivada de las especies comerciales de cucúrbita, pero quizá la que muestra una distribución geográfica más amplia; en estado silvestre no es difícil encontrarla en las zonas altas (1000 a 3000 m s. n. m.) y templadas del continente americano. Esta facilidad se debe en parte a su probada resistencia a varios virus que afectan a otras especies afines, lo que hace más problemática la imposibilidad de obtener híbridos sin medios muy sofisticados.

C. ficifolia requiere suelos húmedos y clima templado; prefiere condiciones de día largo, aunque en regiones cálidas se la cultiva todo el año. No es resistente a las heladas en el primer año de vida.

En algunos sitios se la emplea como patrón para el injerto de plantas de melón (Cucumis melo, otra cucurbitácea).

Ambiente

Los cultivares forman parte de agrosistemas y se encuentran generalmente en huertos familiares, se le puede localizar en climas templados y cálido-húmedos.[6][5]

Cuando es escapada al cultivo, puede constituirse en distintos tipos de vegetación de acuerdo a la región del cultivar, desde vegetación ruderal, acahuales derivados de selvas tropicales, bosque mesófilo de montaña y bosques templados.[26]

Se cultiva en varios tipos de suelo, aunque prefiere aquellos que son capaces de retener humedad y con buen drenaje, aunque no soporta suelos totalmente arcillosos. Tolera suelos pobres en nutrientes, muy húmedos y poco drenados, se adapta tanto en suelo con pH básico, neutro y ácido. Es una especie cultivada, principalmente en toda América Latina, ocupando zonas de altitud media a alta, en climas tanto cálidos como templados. Para esta especie el rango de altitud es de 1000-3000 m).

Estado de conservación

Es la especie menos diversa de todas las especies cultivadas de Cucurbita y no se sabe que existan cultivares comerciales de ella. Desde el punto de vista agronómico es posible pensar en la existencia de cierta diversidad genética para las poblaciones de C. ficifolia, debido a que se cultiva en regiones uniformes en altitud pero que seguramente son más diversas en cuanto a otros factores ecológicos locales, además de ser una especie cultivada tanto en sistemas agrícolas de alta competencia (milpas de temporal), como de un manejo más intensivo (milpas cultivadas en épocas de sequía) y recientemente a la detección de colecciones resistentes a enfermedades virales[6][5].

Los bancos genéticos "ex situ" han representado la forma de conservación más importante, debido a que la conservación "in situ" es casi nula, aunque debe implementarse este tipo de conservación, puesto que solamente de esta forma se mantendrán vivos.[6] No es una especie registrada bajo alguna categoría de riesgo.

Empleo
Pepas de sambo (semillas de Cucurbita ficifolia) tostadas. En Ecuador son usadas para la preparación de diferentes recetas.

Las flores y brotes tiernos de C. ficifolia se emplean en México y otros países americanos como verdura, de manera similar a la fiore di zucca (la flor de Cucurbita pepo y Cucurbita maxima) utilizada en la cocina italiana. También se emplea el fruto inmaduro, pelado y hervido.

El fruto maduro con el agregado de azúcares se consume como dulce y se utiliza para elaborar bebidas. En confitura se emplea para la confección de cabello de ángel, un dulce elaborado acaramelando las hebras de la pulpa con jarabe de azúcar. En México, al igual que la calabaza, suele prepararse cristalizado (confitado), y se conoce como «chilacayote en dulce». En Chile, la conserva de la fruta cocida en azúcar se conoce como «mermelada de alcayota».

Las semillas, ricas en lípidos y proteínas, son el ingrediente principal de un típico postre de la región mexicana de Chiapas, las palanquetas. Las semillas también se comen saladas y tostadas en diversas regiones de ese país.

En Ecuador, el fruto tierno es usado para preparar sopa de sambo, locro de sambo y fanesca. Con el maduro se hace dulce de sambo. A la semilla se la conoce como pepa de sambo y es utilizada tostada y molida en diferentes recetas.[57][58][59]

Taxonomía

Fue nombrada por primera vez acorde a las reglas del Código como Cucurbita ficifolia por Bouché en 1837.[cita 15] La cita completa, según (1) Bailey (1929[60]:105) y (2) según Lira Saade (1995[3]:67):

  • (1) Cucurbita ficifolia, Bouché, in Verh. der Ver. des Gartenb. Berlín, xii, 205 (1837).
  • (2) Cucurbita ficifolia, Bouché, Verh. Vereins Beförd. Gartenbaues Königl. Preuss. Staaten 12: 205. 1837. Tipo: no conocido.

Otros nombres:

  • Cucurbita melanosperma Aparentemente ya se la utilizaba en los catálogos de semillas bajo ese nombre, y según Andrés (1990[cita 15]) bajo ese nombre fue descripta por Gasparrini en 1848, nombre que fue utilizado por autores posteriores (Braun et al. 1853, Naudin 1856, 1857, 1865, 1866, otros), presumiblemente sin conocimiento de la primera descripción. Bailey (1929[60]:105) en su descripción de C. ficifolia la lista como sinónimo de Cucurbita melanosperma, Gaspar., Act. Acad. Napol. (1847), and Ann. Sci. Nat. ser. iii, ix, p.208, t. 9; A. Braun, Cat. Hort. Karls. 1824, nomen nudum. Lira Saade (1995[3]) la lista como Cucurbita melanosperma Gasp., Rendiconti Reale Accad. Sci., Napoli 6:448. 1847.
  • Pepo ficifolia, Britton, Sci. Survey Porto Rico and Virgin Is (N. Y. Acad. Sci.), vi, 266 (1925) (o 1825?) (como listado en Bailey 1929[60]:105). Pepo ficifolius (Bouché) Britton, Bot. Porto Rico 6: 266. 1925. (como listado en Lira Saade 1995[3])
  • Pepo malabaricus (Sageret 1826) no fue un nombre válido debido a que no estaba acompañado de una descripción o una indicación de dónde encontrar la descripción, ni un espécimen. (comentario de Andrés 1990[cita 15]) Lira Saade (1995[3]) la lista como Pepo malabaricus Sageret, Mém. Acad. Agric. France 1: 102. 1827. Nomen nudum.
  • Cucurbita mexicana Hort. (1891) aparentemente describe una variedad de la especie por lo que es un sinónimo del primer nombre (Andrés 1990[cita 15]). Lira Saade (1995[3]) la lista como Cucurbita mexicana Hort. ex Dammann Cat. 42. 1890-1891. Nomen nudum.

Nombres de variedad sinonimizados.

  • Cucurbita ficifolia var. mexicana G. Nichols., III. Dict. Gard., Suppl. 1: 272. 1900. (tomado de Lira Saade 1995[3])
  • Cucurbita ficifolia f. leucosperma Zhiteneva, Bull. Appl. Bot. Genet. & Pl. Breed., Leningrad, Suppl. 47: 301. 1930. (tomado de Lira Saade 1995[3])
  • Cucurbita ficifolia f. melanosperma Zhiteneva, Bull. Appl. Bot. Genet. & Pl. Breed., Leningrad, Suppl. 47: 301. 1930. (tomado de Lira Saade 1995[3])

Nombre común

Originaria de los Andes americanos, es conocida con una variedad de nombres locales entre los que están los que parecen ser derivados del mismo término nativo: alcayota, cayote, lacayote, chiclayo, chilacayote (en cambio no chayote), además de otros como chiverre, y otros de origen español como bolo, cabello de ángel, calabaza confitera, cidra, vitoria, victoria o zambo. El nombre nativo de muchas regiones parece derivado de tzilacayotli, nombre nahuátl. El nombre puede haberse propagado con el de una variedad exitosa. El vocablo Chilacayota procede del náhuatl “tzilac” = liso y ”ayotli” = calabaza, por lo tanto se puede traducir como calabaza lisa. Sin embargo, el origen de la planta no es de México, al parecer la evidencias de su origen se encuentra en la zona andina de Perú.

Por país
Frutos en el Día de los Muertos mexicano
  • Argentina: alcayota (en Cuyo) o cayote (en el noroeste argentino)
  • Bolivia: lacayote
  • Brasil: gila-caiota
  • Chile: alcayota
  • Colombia: calabaza, vitoria o bolo
  • Costa Rica: chiverre
  • Ecuador: sambo
  • El Salvador: chilacayote
  • España: cidra, sidra cayote, sidra, calabaza de sidra, pantana, cabello de ángel.
  • Guatemala: chilacayote, cidracayote
  • Honduras: chiberro
  • México: chilacayote, chilaca, kan
  • Perú: chiuche (Cajamarca), calabaza blanca (Lima), lacayote (Arequipa), chiclayo (Amazonas), zambumba o sambumba (Piura)[72]
  • Portugal: chila, chila-caiota
  • Venezuela: cabello de ángel

Por nombre
  • Alcayota (en Chile y en provincias de Cuyo: Mendoza, San Luis y San Juan, Argentina)
  • Alcayote
  • Ayote (Guatemala)
  • Blanca (Bolivia)
  • Bolo (Colombia)
  • Cabello de ángel (Venezuela y algunas zonas del sur de España como las comarcas del norte almeriense: Los Vélez, Almanzora...)
  • Calabaza
  • Calabaza blanca (Perú)
  • Calabaza china (Cuba)
  • Cayote (en Salta, Tucumán y Jujuy, Argentina)
  • Chiclayo (Perú)
  • Chila (Portugal)
  • Chilaca (México)
  • Chila-caiota (Portugal)
  • Chilacayote (México, Guatemala y El Salvador)
  • Chiverre (Costa Rica)
  • Cidra (España)
  • Cidra cayote (España)
  • Cidracayote (Guatemala)
  • Gila-caiota (Brasil)
  • Kan (México)
  • Lacayote (Perú y Bolivia)
  • Lacayute
  • Mexicano
  • Pantana (Canarias)
  • Sambo (Ecuador)
  • Sambumba (Perú)
  • Tzilicayotli (/chili-kaiotli/) en idioma náhuatl
  • Vitoria (Colombia)
  • Zambumba (Perú)
  • Zapallo (Venezuela)

Notas
  1. Andres (1990[2]): "Several investigators have attempted to cross C. ficifolia with the other cultivated species. Successful hybrids have been produced in a very low percentage of the pollinations between C. ficifolia and C. maxima, C. moschata, and C. pepo (Drude 1917[18], Grebenscikov 1965[19], Naudin 1865[20], Van Eseltine 1936[21], Weiling 1955[22], Whitaker 1956[23], Whitaker and Davis 1962[8], T.C. Andres, unpublished data). Only partially developed embryos form, and embryo culture must be employed to obtain subsequent generations. Unfortunately, sterility barriers have thus far prevented obtaining progeny beyond the F1 and first backcross generations. Variable results, however, have been obtained when different cultivars of a species are used. It is hoped that more compatible cultivar combinations may exist. Whitaker and Bemis (1964[7]) state that a fig-leafed form of C. ficifolia is probably allied with C. pepo or C. maxima, whereas a form with moschata-like leaves is probably closely related to C. moschata. Evidence for these two forms was not documented nor have they been observed by the author."
  2. Andres (1990[2]): "Biosystematic evidence indicates that the species is not as highly distinguished morphologically and genetically from the other domesticated squashes as was once believed; it does not differ from these other species in having perennial rather than annual growth habit as has been widely reported, and it may be hybridized to them by the use of embryo culture."
  3. Andres (1990[2]): "Several characters have been incorrectly used to separate C. ficifolia from the other four domesticated species of squash, the most notable being perennial versus annual habit. Taxonomic keys to the squashes invariably delineate C. ficifolia as the only perennial cultigen in the genus (Whitaker and Bemis 1964[7], Whitaker and Davis 1962[8]); however, no morphological features are ever given by which the duration of the plant can be recognized. To further confuse matters, it is sometimes stated that C. ficifolia is perennial but is often cultivated as an annual (Bailey 1948[9], Dieterle 1976[10]). - It is now evident that C. ficifolia does not differ in longevity from the other squash species. All domesticated species of Cucurbita have extensive fibrous root systems and indeterminate growth. Under suitable growing conditions, each of these species, with the exception of bush varieties, will continue to grow indefinitely when the stems are permitted to root at the nodes. Cucurbita ficifolia is tolerant of low temperatures, although it and all species of Cucurbita are frost-tender (Tachibana 1987[11]). Cucurbita ficifolia, however, is grown in the high-altitude tropics, where it will often maintain vigor through the cool winters while the other, less cold-tolerant species perish, thereby appearing to differ from the other cultivated cucurbits grown in the same region. In warmer climates, landraces of C. moschata have been reported to last for several years (Morton 1975[12]), although this species is generally reported to be an annual. All of the domesticated squash species are usually grown as annuals, but in their native habitats, i.e., the presumed habitat of their wild progenitor, they may grow spontaneously as short-lived herbaceous perennials."
  4. Andres (1990[2]): "What little variation in C. ficifolia appears to occur throughout its range. The buff-seeded form, occurs througout the range, usually in the same field with black-seeded plants. The fruits have basically three different color patterns that occur throughout Mexico, Central America, and South America (Figure 2): all white; a distinct reticulated pattern of green on white, sometimes with ten radial stripes spreading from the apex to the base; and dark green, without reticulations but sometimes also with white longitudinal stripes. Slight variations of the reticulations and stripes occur, but nothing like the wide assortment of color variants, warts, corky outgrowths, and shapes and sizes that occur in the fruits of the other domesticated species. There is no association between seed color and fruit color. Uses of these various forms of C. ficifolia are generally the same and no named cultivars have been recognized."
  5. Andres (1990[2]): "Whitaker and Bohn (1950[13]) report that C. ficifolia seems to require a short photoperiod for flowering, whereas the other domesticated species are insensitive to day lenght. While this is generally true, not all accessions of C. ficifolia require short-days for flowering, and many landraces of other Cucurbita species are short-day plants. There are accessions of C. ficifolia that produce fruits at the extreme latitude of Norway (Janson 1923[14]). On the other hand, there are accesions of squash, primarily in the species C. ficifolia and C. moschata, that do not flower north or south of the torrid zone."
  6. Andres (1990[2]): "In contrast (with C. pepo, C. maxima, C. moschata, C. argyrosperma), C. ficifolia is relatively homogeneous in morphology and genetic composition. This facilitates recognition of the species but has given a misleading impression of its uniqueness. The fruits, which are the part of the plant most likely to have undergone diversification as a result of human selection, are relatively uniform in shape, rind and flesh characteristics. This is in marked contrast to the other species of squash, in which numerous cultivars of striking variation exist."
  7. Andres (1990[2]): "Other morphological features of C. ficifolia have been adequately described elsewhere (Bailey 1937[15], Bailey 1948[9], Bukasov 1930[16], Naudin 1856[17], Whitaker and Bohn 1950[13]). The stem trichomes of C. ficifolia are setaceous, like those of C. maxima. The peduncle is hard, smoothly angled, and slightly flaring at the attachment to the fruit, like that of C. ecuadorensis and some landraces of C. moschata. The exterior color and shape of the fruit are very similar to some landraces of C. maxima; and the fruit flesh is white, somewhat dry, and coarsely fibrous, like some forms of C. argyrosperma. The fruits of C. ficifolia, which range from 15 to 50 cm long, with reports by roadside vendors of up to 100 cm long, are sometimes even confused with watermelon, Citrullus lanatus (Thunb.) Matsum. & Nakai, a case of convergent rather than parallel evolution."
  8. Andres (1990[2]): "...In summary, of the three characters most often used in taxonomic keys to identify C. ficifolia, one is misinterpreted (perennial growth habit), one is not unique to C. ficifolia (leaf shape), and the third is not always true for C. ficifolia (black seeds)."
  9. Andres (1990[2]): "A final character that is often mistakenly used to distinguish C. ficifolia from the other species of Cucurbita are the leaves shaped like those of Ficus carica L., hence the specific epithet. Other species, such as C. lundelliana L. H. Bailey, C. ecuadorensis Cutler & Whitaker, and some landraces of C. moschata and C. pepo may also have figlike leaf shapes. Furthermore, most species of Cucurbita and many other related genera are heterophyllous, with late-developing leaves generally more deeply lobed than those produced early in the growth cycle. Unfortunately, most herbarium specimens of cucurbits include only one stage of leaf development. This variation in leaf shape has perhaps contributed to an excesive splitting of the number of described species of Cucurbita and led Bailey (Bailey 1948[9]) to believe there was another undescribed pecies of black-seeded gourd.Nota del autor: "Bailey grew the unidentified accession with black seeds in Ithaca, New York, but the plants were evidently sensitive to a short-day photoperiod and never produced fruits. The voucher specimens indicate that they are C. ficifolia.""
  10. Andres (1990[2]): "One character used to delineate C. ficifolia is the color of its seeds. It is the only species of Cucurbita with black seeds, but not all C. ficifolia seeds are black; some may be dark brown, while others are more or less pale buff-colored like those of most other species of Cucurbita (Figure 1). Bukasov (Bukasov 1930[16]) listed two forms of C. ficifolia based on the seed colors, C. ficifolia f. melanosperma and C. ficifolia f. leucosperma. There are landraces of C. moschata grown in northern South America that also have dark brown seeds."
  11. Andres (1990[2]): "There are several characters that may be used, at least in concert, to distinguish C. ficifolia from all other species. As already mentioned, C. ficifolia is the only species of Cucurbita with black seeds, but some forms and immature seeds are light buff-colored as in other cucurbits. The shape of the seeds is fairly diagnostic, however. They are large, 15-25 mm in lenght, and oblong-ellipsoidal with a width-to-lenght ratio of 3:2, which is generally broader than tha in the other cucurbit cultigens. They are flat in cross section and hard, without a thick, spongy epidermis that is characteristic of the seeds of C. maxima (Singh and Dathan 1972[24]) and some forms of C. argyrosperma. Furthermore, the surface of the seed appears minutely pitted or pebbled and not polished or crazed like the surface of the seeds of C. maxima. There is a uniformly thin margin around the edge of C. ficifolia seeds with the same color and texture as the rest of the seed."
  12. Andres (1990[2]): "A more reliable distinguishing feature of c. ficifolia, which has not been reported previously, is the presence of trichomes on the filaments in the male flowers. Most other species of Cucurbita have glabrous filaments or filaments with just a few scattered trichomes at their base. The only exceptions to this are C. foetidissima HBK, C. pedatifolia Bailey, and C. radicans Naud., which also have these trichomes, albeit shorter ((menor que) 1 mm in lenght) than those of C. ficifolia ((mayor que) 1 mm in lenght and clearly visible without a hand-lens). Trichomes on the axis of C. ficifolia, particularly along the growing tips and young leaves, bear a brown glandular resin that will stain the fingers."
  13. Andres (1990[2]) p.109-110: "Origin and Distribution. Like all other species of Cucurbita, C. ficifolia originated in the Americas. It is presently grown in many tropical highland regions of the world, including south-central Asia and the Philippines (Herklots 1972[27]). However, it is primarily used under sustainable agriculture systems in Latin America, where personal observations and herbarium records show that it is generally grown between 1000 and 2800 m above sea level. The Latin American distribution of C. ficifolia exceeds that of all the other cultivated Cucurbita species, extending from the highlands of northern Mexico, through Central America, and throughout Andean America from Colombia and Venezuela to central Chile and northwestern Argentina. The climate in these areas is generally very moist and too cool for any other species of squash to grow, except for some short-season landraces of C. pepo and C. maxima. - The first fruits of C. ficifolia to reach Europe apparently took a circuitous route from South America to the Malabar coast of India along the much traveled Portuguese and Dutch trade routes in the 16th and 17th centuries, before finally reaching Europe (Merrill 1954[28]). Bouché (1837[29]) did not know where his cultivated material came from, but vernacular names such as melon de Malabar (Malabar melon), courge de Siam (Siam squash), and Anguriankurbis (Angora squash) suggested a southern Asian origin. - In 1854 a well-documented shipment of yaks was introduced to France from the border of Tibet with India. In Shanghai a large quantity of C. ficifolia fruits were loaded to serve as fodder for these animals during the long ocean voyage. More than a year after the voyage ended many of these fruits were left over and still intact at the Muséum d'Histoire Naturelle, Paris. They became a curiosity in European botanical gardens. This convinced the botanists of the time and for many years afterward that C. ficifolia was native to the Orient (Bailey 1937[15], Bukasov 1930[16], Cogniaux 1881[30], Naudin 1857[31]). However, De Candolle (1886[32]) doubted this because all known perennial Cucurbita species were native to North America. He assumed that only the "annual" species were of Old World origin. - The etymological, ethnobotanical, and archaeological evidence prove that C. ficifolia is of American origin. In Asia, C. ficifolia is primarily used only for livestock feed, and no Sanskrit name exists, whereas in Latin America there are archaeological records and many local names and uses of the plant. The most frequently used vernacular name for C. ficifolia in Mexico and parts of Central America is chilacayote (also spelled chilacayota, chilacayoti, chilacayotl, and other variations), probably a corruption of tzilacayotli, but other names include alcayota, pachayota, silacayote, cuicuilticayotli, cidracayote, cidra, mail and chiberre, chibesse, or chiverre (the latter three names used only in Costa Rica) (Bukasov 1930[16], Robelo 1904[33], Rose 1899[34], Watson 1887[35]). Martínez (1979[36]) lists several additional Mexican names of generally Nahuatl origin for C. ficifolia. In Colombia, C. ficifolia is usually referred to as anjama, victoria, or vitoriera; in Venezuela, the Quechuan name zapallo is generally used for all Cucurbita; and in Ecuador, zambo (zambu, sambo or tambo) is used. The names used in Bolivia, Peru, and northern Argentina, in the Quechua and Aymara language areas, are surprisingly similar if not identical to the Mexican names: lacayote or lacahuiti, silacayote, alcayote or alcallota, cayote, and tintimoro. "
  14. Andres (1990[2]) p.110-114: "While C. ficifolia was clearly cultivated in Mexico prior to the Spanish conquest, it is uncertain where it was first domesticated in its extensive Latin American range. The etymological evidence is inconclusive at best in this regard The Nahuatl names could be derived from or precede the similar sounding Quechuan and Aymara names. For example, Francisco Hernández in the 16th century was the first to clearly describe the chilacayote in Mexico (see Urbina 1902-1903[37]). He speculated that the Nahuatl name, tzilacayotli, is derived from either the words tzilac-ayotli, meaning "smooth calabaza or squash", or tzilictic-ayotli, meaning "squash that resonates or sounds" when struck. The name cuicuilticayotli literally means the "painted squash". Even if Hernández is correct, these names may still be derivations from South America that have taken on slightly new meanings in Nahuatl by folk etymology.
    Sahagún (1956[38]), a Franciscan friar, recorded in the 16th century that the hollowed-out fruit of tzilacayotli was used by the Aztecs as a bowl to contain offerings, such as pulque, for their deities. The bowl was placed in front of the image or images, and with their marbled appearance, were said to be made of precious stones which the Aztecs called chalchihuitl. This religious practice suggests an ancient use, if not origin, in Mexico and subsequent spread to the south.
    The archaeological record tells a different story. Numerous seed remnants and pedicels of C. ficifolia have been recovered from archaeological sites along the central to northern coastal desert of Peru. These have been recovered from several horizons spanning several thousand years, beginning from a pre-ceramic, pre-maize horizon dated at 3000 B.C. (Bonavia 1982[39], Towle 1961[40]). In contrast, no definitive archaeological specimen of C. ficifolia has been found north of South America. A single seed, recovered from the Valley of Oaxaca, dated at 700 A.D., and tentatively identified as C. ficifolia (Whitaker 1981a[41], Whitaker and Cutler 1971[42]), appears instead to be C. pepo.
    Despite the archaeological record, C. ficifolia is generally considered to have originated in Mesoamerica, specifically southern Mexico and Guatemala (Bukasov 1930[16], Hurd et al. 1971[43], Sauer 1969[44], Vavilov 1949-1950[45], Whitaker 1980[46], Whitaker 1981b[47]). This conclusion is based on several lines of circumstancial evidence in addition to that already mentioned and suggests a pattern of dispersal evident in the often closely associated crops maize, beans, and the squash species, C. pepo. On the basis of the estimated time taken for C. ficifolia to have diffused from Mesoamerica to Peru by 3000 B.C., Cutler and Whitaker (1961[48]) concluded that it must be the oldest cultivated plant in the Americas.
    Sauer (1969[44]) noted that C. ficifolia is absent today from the hot, dry lowland region where the archaeological specimens were found. He concluded from this that C. ficifolia must be an ancient yet still primitive cultigen that was dropped from cultivation except in the cool high country when better squashes were developed. He did not consider the possibility that these archaeological squashes were not autochthonous but were instead brought down from farms at higher altitudes. Cohen (1977[49]) presented evidence that the early Peruvian coastal cultures depended primarily on resources from the ocean and trading with the Andean cultures. Agriculture was initially of lesser importance in the lowlands than at the higher elevations. The earliest archaeological seeds of C. ficifolia are the same size as those today, which suggests that it was an imported domesticate.
    Hurd et al. (1971[43]) used two genera of solitary bees (Peponapis and Xenoglossa), commonly known as squash and gourd bees, to help discern the species relationships in the genus Cucurbita. These bees depend almost exclusively on squash flowers for pollen and nectar for themselves and their larvae, and therefore appear to have coevolved with the cucurbits. The center of diversity of these bees occurs in southern Mexico, where the greatest concentration of Cucurbita species is located.
    There is one species of squash bee, P. atrata (Smith), which is reported to be restricted to the pollen of C. ficifolia (Hurd et al. 1971[43]). It is found only in the highlands of Mexico and adjacent Central America and not in South America. There are other more generalized species of squash and gourd bees, which occur throughout the Americas and use the pollen of all the cultivated species of squash, including C. ficifolia. The absence of P. atrata in South America is used as evidence to support the hypothesis that C. ficifolia was introduced by humans into South America from Mexico (Hurd et al. 1971[43]). This is based on the assumption that P. atrata did not concordantly extend its range into South America with C. ficifolia because it was unable to cross the intervening lowland areas. Before reaching a definitive conclusion about human dispersal of C. ficifolia based on the distribution of its pollinators, a thorough sampling needs to be conducted on the species of pollinators visiting C. ficifolia flowers throughout its range, including South America. Peponapis atrata may not be as monolectic as reported in the literature; a female P. atrata was collected from a flower of C. argyrosperma in Chiapas, Mexico in December, 1985 (specime collected by T.C. Andres and species determined by W.E. LaBerge; deposited in the Cornell University Insect Collection, lot number 1166).
    The hypothesis resulting from the squash and gourd bee study of Hurd et al. (1971[43]) are not conclusive. While they are derived from extensive field observations, they have not been tested experimentally. The study did not demonstrate whether the various species of bees coevolved with specific species of Cucurbita or with the genus in general. The latter is the rule among oligolectic bees (G.C. Eickwort, pers. comm., 1988). The fact that these bees and Cucurbita species share centers of diversity may not be due to their coevolution but rather to other causes such as their independent adaptation to the extreme habitat diversity of the region. Experimental tests need to be conducted to determine if species such as P. atrata, given the choice between C. ficifolia and other species of Cucurbita, are able to differentiate between them.
    Hurd et al. (1971[43]) stated that the pollen collecting devices of the bees are species-specific, being adapted to carry the pollen grains of different Cucurbita species, which vary in size and structure. However, Andres (1981[50]) showed by light and scanning electron microscopy that the pollen exine characteristics of Cucurbita do not show significant variation between species and therefore probably do not play an important role in the evolution of the pollinators.
    There are also few consistent morphological differences in the flowers of Cucurbita species. For example, the ultraviolet patterns, i.e. "nectar guides", are indistinguishable among Cucurbita species (T.C. Andres, unpublished observation). Whether the bees are able to cue in on other interspecific differences in the cucurbit flowers has yet to be determined.
    Whitaker (1980[46], 1981b[47]) and Whitaker and Davis (1962[8]) also assume that C. ficifolia was domesticated in Mesoamerica rather than South America. This conclusion is based on compatibility data and the distribution of the possible wild progenitors. Cucurbita ficifolia and C. moschata are the only domesticated species of squash with no known logical wild ancestor. Whitaker (1980[46]) suggests that C. ficifolia may be derived from the wild mesophytic species, C. lundelliana or C. martinezii L. H. Bailey. Evidence from comparative morphology, geographic distribution, ecology, and genetic relationships do not, however, indicate a very close relationship between these wild species and C. ficifolia. Cucurbita lundelliana is the only wild mesophytic cucurbit that has been reported to cross with C. ficifolia, but attempts to obtain subsequent generations have failed because of sterility factors (Whitaker 1980[46]). Furthermore, pollen fertility was reported to be higher in the F1 hybrids between C. lundelliana and the other domesticates than between C. lundelliana and C. ficifolia (Whitaker 1956[23]). Neither wild species occurs in the cool highland areas where C. ficifolia is grown; C. lundelliana is confined to the Yucatan peninsula, which includes a part of the countries of Mexico, Belize, and northern Guatemala, whereas C. martinezii extends from southern Tamaulipas, through Veracruz to northern Chiapas, Mexico. These two species are closely related and both have small gray colored (green when wet) seeds that bear little resemblance to those of C. ficifolia.
    A recent extensive crossing program showed that when C. ficifolia is used as the pistillate parent it may be crossed with the interfertile xerophytic species, C. foetidissima and C. pedatifolia, without the need for embryo culture (Andres 1987[51]). Sterility barriers prevented obtaining subsequent generations. These two xerophytic species and C. radicans share with C. ficifolia pubescent filaments but otherwise bear little resemblance to C. ficifolia in morphology and ecology. In the study on the relationships of Cucurbita species with the squash and gourd bees (Hurd et al. 1971[43]), however, C. pedatifolia was grouped with C. ficifolia.
    In South America there are less likely candidates for the wild progenitor of C. ficifolia. Only two wild species of Cucurbita are endemic to South America. One, C. andreana Naud., is fairly certain to be the wild progenitor of C. maxima (Millán 1945[52]). The other, C. ecuadorensis, has some phenetic similarity to C. ficifolia, such as the similar leaf shape already mentioned and an unusually large ruit for a wild cucurbit, but crossing studies indicate it is more closely aligned with C. maxima and the C. lundelliana group (Cutler y Whitaker 1969[53]).
    There is perhaps more persuasive evidence suggesting that C. ficifolia originated in northern South America rather than Mesoamerica. Intensive searches for a compatible wild progenitor of C. ficifolia in Mexico have produced no evidence of any such populations. Although less intensive searches have been conducted south of Mexico, there are sketchy reports of possible wild or at least spontaneous populations. Dieterle (1976[10]) reports populations of C. ficifolia in some highland localities of Guatemala to "have become thoroughly naturalized and look like native plants." The difference between wild and naturalized populations of cucurbits is often ambiguous or at least difficult to determine. In Colombian markets Cardenas (1969[54]) reported seeing "victoria" squashes with "necks like a bottle". This shape has not been found elsewhere and, if this report is correct, may represent a primitive character or a derived morph from an ancestral population. In Bolivia, Cardenas (1969[54]) reported that C. ficifolia plants with viviparous seeds appear wild because they are spontaneous and hanging off the mountain sides. No description or documentation is provided on the morphology of the plants. Granado (1931[55]) stated that C. ficifolia originated in Bolivia, but he did not provide any evidence. Agronomists at Inquisivi, Departamento La Paz, reported a wild form of C. ficifolia, but this has not yet been confirmed (M. Nee, pers. comm., 1988).
    The hypothesis of an Andean origin and domestication of C. ficifolia rather than a Mexican origin explains the archaeological record and does not neccesitate a change in habitat as Sauer proposed (Sauer 1969[44]). Cucurbita ficifolia is most likely uniquely adapted to cool, moist conditions because it evolved in a habitat characterized by such a climate. The preponderance of short-day flowering accesions points to an area of origin within the torrid zone. If domestication occurred in the northern Andes around or before 3000 B.C., there was ample time for a gradual spread of the crop to the north and use by the Aztecs in Mexico beginning in the 12th century. A similar situation occurred in C. pepo, which spread northward during pre-Columbian times from central and northern Mexico to southwestern and eastern Unites States to as far north as adjacent Canada (Whitaker and Bohn 1950[13], Whitaker and Davis 1962[8]). However, in the case of C. pepo, this dispersal may have occurred several millennia before C. ficifolia was even domesticated, thus allowing sufficient time for secondary diversification of cultivars to occur within the new range (see Decker, this volume). Other examples of New World crops involved in very early long distance cultural exchanges include peanuts and guava, which spread from Peru to Mexico by 200 B.C., and maize, which spread from Mexico to Peru by around 3000 B.C. (Flannery 1973[56]).
    It is conceivable that there are still extant wild conspecific populations of C. ficifolia in some isolated cool forests on the eastern flank of the Andes in Venezuela, Colombia, Ecuador, Peru, or Bolivia. Furthermore, in such an area this species may contain greater genetic diversity than has been found elsewhere. Germplasm collecting and evaluations need to be conducted in this region. There are few dry caves in this region where archaeological preservation could have occurred, but those fruits that were traded with cultures along the dry Peruvian coast may have been preserved. This type of trading of the highland grown C. ficifolia for lowland crops, such as C. moschata, still takes place today in much of Latin America."
  15. Andres (1990[2]): "Nomenclature. Cucurbita ficifolia was described by Bouché in 1837 (Bouché 1837[29]), however, the species was first reported in Europe and named C. melanosperma by Braun in 1824 in a seed catalog from Carlsruhe Garden, Germany, but without a description or indication of place of origin (Bois y Gerome 1920[61], Walpers 1857[62]). Gasparrini (1848[63]), apparently unaware of either earlier publication, also used the name C. melanosperma in his 1848 description of the species. Braun et al. (1853[64]) later described C. melanosperma in detail, and this name was subsequently used by Naudin (1856[17],1857[31],1865[20],1866[65]) and others. However, the name C. ficifolia has priority. In addition to C. melanosperma, another name preceded Bouché's. Pepo malabaricus was proposed by Sageret in 1826 (Sageret 1826[66], Sageret 1827[67]) for the "melon du Malabar", a vernacular name used in France for the fig-leaf gourd. Because there was no accompanying description or reference to a publication or a specimen, the name was not validly published (Bailey 1929[60]). In the late 1800's C. mexicana Hort., originally described in the Dammann Catalogue (1890-1891[68]), was cited (Anonymous 1891[69]) as a unique species from Mazatlan, Mexico, "very similar to C. melanosperma, but with the leaf of a different shape, and flower of a different hue, the seeds are large and black". There is nothing in the description to indicate this name to be anything but a synonym of C. ficifolia, the only known species of Cucurbita with black seeds. Two species have been incorrectly ranked as varieties or cultivars of C. ficifolia in the past, including C. argyrosperma Huber (Bailey 1937[15], Hutchins y Sando 1941[70]) and C. moorei L. H. Bailey (Filov 1966[71]), which is probably a synonym for C. pedatifolia L. H. Bailey (T. C. Andres, unpublished observation).

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