Cultivar-Groups in Cucurbita Maxima Duchesne: Diversity and Possible Domestication Pathways

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Review Cultivar-Groups in Cucurbita maxima Duchesne: Diversity and Possible Domestication Pathways

Fernando Sebastián López-Anido

Cátedra de Genética, Facultad Ciencias Agrarias, Universidad Nacional de Rosario-IICAR Conicet, Zavalla S2125ZAA, Argentina; [email protected]

Abstract: Domesticated Cucurbita has been remarked as one of the plant genera with the highest diversity in color, shape and fruit dimensions. Their economic and cultural values are related to the consumption of the mature or immature fruits, seeds, flowers, and to the use as decoration. The wild ancestor of C. maxima, the ssp. andreana has an actual scattered and disjointed distribution, associated with megafauna seed disperser syndrome. It was domesticated in South America around 9000–7000 years BP. The cultivar-group is a subspecific category for assembling cultivars on the basis of defined similarity. The work describes and pictures nine cultivar-groups for the species, Banana, Turban, Hubbard, Show, Buttercup, Zapallito, Plomo, Zipinka and Nugget. The molecular and a morphological join data analysis scatter biplot showed Turban and Buttercup in a central position, suggesting a first step in the domestication pathway associated with seed and immature fruit consumption; afterward, bigger bearing fruits groups were selected for their mature fruit flesh quality on one hand, and bush type, short day induction and temperate climate adaptation on the other hand. The striking domesticated Brazilian accession MAX24 intermediate between cultigens and ssp. andreana strengthens, in concordance with archeological remains, the possible domestication place of the species more easternward than previously believed.

Citation: López-Anido, F.S. Keywords: pumpkin; domestication; cultivar-groups Cultivar-Groups in Cucurbita maxima Duchesne: Diversity and Possible Domestication Pathways. Diversity 2021, 13, 354. https://doi.org/ 10.3390/d13080354 1. Cucurbita 1.1. Extant Wild Species Academic Editor: Mario A. Pagnotta Cucurbita (2n = 20) is a well-defined New World genus within the tribe Cucurbitae [1]. Wild species are herbaceous, multi-branched, procumbent or climbing vines. The stems are Received: 10 July 2021 slender, and the leaves are arranged on them alternately [1]. Plants are monoecious and Accepted: 30 July 2021 predominantly staminate, with large yellow-orange (rarely pale yellow) flowers pollinated Published: 31 July 2021 in early morning by solitary bees of the genera Poponapis and Xenoglossa [2]. Fruits are small (5–10 cm long), round, indehiscent, with a lignified rind, thin fibrous, light-colored or pale Publisher’s Note: MDPI stays neutral usually bitter flesh and numerous, relatively small seeds [3]. Around twelve wild species with regard to jurisdictional claims in are generally recognized; six belong to the perennial, xerophytic group, Cucurbita cordata published maps and institutional affil- Watson, C. digitata Gray, C. foetidissima Kunth, C. palmata Watson, C. pedatifolia Bailey and C. iations. radicans Naudin. This group has a distribution range from southern-western United States and Baja California to northern-central and southern Mexico [4]. The annual, mesophytic group comprises Cucurbita argyrosperma Huber ssp. sororia Merrick & Bates, C. lundelliana Bailey, C. okeechobeensis Bailey ssp. martinezii Andres and Nabhan and ssp. okeechobeensis, C. Copyright: © 2021 by the author. pepo L. ssp. fraterna Lira et al., ssp. ovifera Decker var. ozarkana Decker and var. texana Filov, Licensee MDPI, Basel, Switzerland. C. ecuadorensis Cutler and Whitaker and C. maxima Duchesne ssp. andreana Filov. For this This article is an open access article group, the distribution is more scattered and disjointed, ranging from central United States, distributed under the terms and Florida, Texas, the pacific and gulf coast of Mexico, southern Mexico, northern Central conditions of the Creative Commons America, Ecuador, Peru, Bolivia, northwestern and central Argentina and Uruguay [4,5]. As Attribution (CC BY) license (https:// it is evident, the actual Mexico territory is the center of diversity of wild Cucurbita species. creativecommons.org/licenses/by/ 4.0/).

Diversity 2021, 13, 354. https://doi.org/10.3390/d13080354 https://www.mdpi.com/journal/diversity Diversity 2021, 13, 354 2 of 19

Diversity 2021, 13, 354 northwestern and central Argentina and Uruguay [4,5]. As it is evident, the actual Mexico2 of 19 territory is the center of diversity of wild Cucurbita species.

1.2.1.2. SeedSeed DispersalDispersal InIn thethe majority of of the the botanical botanical and and ecological ecological descriptions descriptions of the of thewild wild CucurbitaCucurbita spe‐ species,cies, the the seed seed dispersal dispersal system system is is overlooked. overlooked. One One of of the the reasons reasons is is that until thethe NewsonNewson andand MihlbachlerMihlbachler [[6]6] findingfinding ofof abundantabundant wildwild CucurbitaCucurbita seedsseeds inin mastodonmastodon dungdung atat the the Page-LadsonPage‐Ladson archeological archeological site, site, no no clear clear evidence evidence for afor zoochory a zoochory mechanism mechanism was recorded. was rec‐ Thisorded. confirmed This confirmed the previous the previous hypothesis hypothesis of Barlow of [ 7Barlow] that C. [7] foetidissima that C. foetidissimawas a clear was example a clear ofexample the megafauna of the megafauna (>1000 kg) (>1000 anachronisms kg) anachronisms syndrome, syndrome, proposed by proposed Jansen and by Jansen Martin and [8]. TheMartin mass [8]. megafauna The mass extinction megafauna around extinction 12,000 yearsaround ago 12,000 left wild yearsCucurbita ago leftspecies wild strandedCucurbita asspecies anachronisms stranded inas aanachronisms post-megafauna in a world,post‐megafauna producing world, fruit that producing few or fruit no animals that few eat, or withno animals seeds that eat, go with undispersed seeds that and go undispersed orphans of mutualistic and orphans partners of mutualistic that shaped partners a mosaic- that likeshaped landscapes, a mosaic offering‐like landscapes, an abundance offering of disturbed an abundance habitat of in disturbed a niche-diverse habitat ecosystemin a niche‐ suitablediverse ecosystem for climbing suitable vines for plants climbing as Cucurbita vines plants[9,10]. as This Cucurbita is crucial [9,10]. to This understand is crucial the to actualunderstand distribution the actual of these distribution species of that these relied, species since that the relied, beginning since ofthe the beginning Holocene, of onthe alternativeHolocene, seedon alternative dispersals seed as buoyancy dispersals of as fruits buoyancy along streams,of fruits along gravity, streams, seed predators gravity, seed and eventuallypredators and anthropogenic eventually activity.anthropogenic This accounted activity. forThis a shrinkingaccounted and for a fragmentation shrinking and in frag the‐ range,mentation and evenin the that range, some and species even could that some have species gone extinct. could Ashave an gone example, extinct.C. okeechobeensis As an exam‐ hasple, an C. allopatricokeechobeensis distribution has an allopatric in Mexico distribution and Florida, in andMexico in the and latter Florida, site, and the populationin the latter wassite, restrictedthe population to the was endoreic restricted basin to of the the endoreic Lake Okeechobee. basin of the Moreover,Lake Okeechobee.C. maxima Moreossp.‐ andreanaver, C. maximashows patchyssp. andreana distribution shows in patchy small specificdistribution populations in small in specific Peru and populations Bolivia [11 in], andPeru in and Argentina Bolivia [11], is associated and in Argentina with disturbed is associated roadsides, with agriculturedisturbed roadsides, field fences, agriculture fallows andfield field fences, drainages fallows [ 12and] (Figure field drainages1). [12] (Figure 1).

FigureFigure 1.1. FruitsFruits ofof C.C. maximamaxima ssp.ssp. andreanaandreana inin anan agricultureagriculture ﬁeldfield wirewire fencefence atat Zavalla, Zavalla, Santa Santa Fe Fe province,province, Argentina. Argentina. LackLack ofof fruitsfruits and and seeds’ seeds’ dispersal dispersal is is apparent; apparent; dry dry light light brown brown ones ones are are from from the previous growing season, yellow‐green ones from the current year. the previous growing season, yellow-green ones from the current year.

1.3.1.3. AnthropogenicAnthropogenic SeedSeed DispersalDispersal ItIt hashas been pointed pointed out out that that bottle bottle gourd gourd (Lagenaria (Lagenaria siceraria siceraria, Cucurbitaceae), Cucurbitaceae) was was car‐ carriedried as asa utilitarian a utilitarian already already domesticated domesticated (mutualism) (mutualism) species species through through Beringia Beringia into into the thenew new world world and andwas wasthereafter thereafter involved involved and reliant and reliant on humans on humans [13]. In [13 this]. Insense, this we sense, can wehypothesize can hypothesize that Paleoindians that Paleoindians as gatherers as gatherers recognized recognized the smaller the smaller gourds gourds of wild of Cucur wild‐ Cucurbitabita with witha potential a potential use and use started and started a virtuous a virtuous circle circle in which in which the gourds, the gourds, that thatwere were mal‐ maladaptiveadaptive of seed of seed dispersers, dispersers, as asthey they became became extinct, extinct, found found in in humans humans a a proxy, alreadyalready familiarizedfamiliarized withwith gourds,gourds, thatthat alsoalso providedprovided disturbeddisturbed nichesniches forfor theirtheir climbingclimbing growth.growth. PaleoindiansPaleoindians byby theirtheir sideside werewere beneﬁtedbenefited byby thethe useuse ofof gourdsgourds as as buoys, buoys, rattles, rattles, smallsmall containerscontainers and and by by the the consumption consumption of of their their protein protein and and oil-rich oil‐rich seeds. seeds. This This anthropogenic anthropogenic seedseed dispersaldispersal mechanismmechanism waswas envisionedenvisioned asas aa startingstarting pointpoint ofof domestication domestication inin manymany plantplant taxa taxa including includingCucurbita Cucurbita[ [14].14].

1.4. Domestication Over the last decade, the idea that domestication was a rapid process (Holocene revolution) began to be seriously questioned. New insights into the pace of domestica-

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tion arose from archaeobotanical studies which show the time it takes for domestication phenotypes to arise and fix in evolving domesticated species is longer than previously thought [15]. One of the reasons of this protracted time could be that many of the crop domestication traits have a polygenic basis, with multiple genes of small effect that could take many generations to be fixed in a population, such as seed size enlargement and fruit size. Another reason is that much of domestication was not, as generally believed, carried out by deliberate, strong selection, but rather is the result of unconscious (natural) selection of incipient species as they were cultivated in the novel, managed environments of Neolithic agricultural fields [15]. This accounts for traits as seed non-dormancy and synchronous germination, but also seed size; larger seed size may be adaptive in several ways, improving competition in early growth patches and survival of the seedlings [16]. One peculiar character that was selected in parallel in three Cucurbita taxa whose fruits are consumed in the immature state is the short internode phenotype that rendered bushy plants, with precocious anthesis and an augmented number of fruits per plant [17–19]. Other traits such as fruit and pulp color and possibly taste clearly were driven by conscious human choice [20].

1.5. Cucurbita in South America Around 3 million years ago, the Isthmus of Panama rose to the actual level connecting the previous isolated Americas and starting what is known as the Great American Biotic Interchange [21]. South America’s newcomer mammals as seed dispersers were involved in the distribution of new plant genera as Cucurbita. Gomphotheres (Proboscidea) is one of the families that colonized and radiated southerly along two corridors; one along the Andes (Cuvieronius hyodon and Stegomastodon waringi); the other route was along the eastern coastal area southward down to the pampas (Stegomastodon platensis) [22]. We can infer that wild Cucurbita spread and speciation in South America were related to these Proboscidae, and the actual distribution and species survival, as mentioned above, was affected by their extinction.

1.6. Natural Cucurbita Pollinators in South America The bees of the Peponapis genus, specialized in Cucurbita species, have a Neotropical distribution with the center of diversity located in Mexico. Peponapis fervens is the only species of the genus known from southern South America [23]. Using ecological niche modeling, the potential geographical areas of this species were determined and found to extend north beyond the latitude of 20◦ S, including some areas of northeastern and central western Brazil, northern Argentina and Bolivia, which is much larger than the actual distribution range of ssp. andreana [23].

1.7. Domesticated Cucurbita Species Domesticated Cucurbita has been remarked as one of the plant genera with the highest diversity in color, shape and fruit dimensions. Five species in decreasing order of importance are now cultivated worldwide, i.e., C. pepo; C. moschata; C. maxima; C. argyrosperma and C. ficifolia; and, in production as a whole, they are positioned among the ten most important world vegetables crops [24]. Their economic and cultural values are related to the consumption of the mature or immature fruits, seeds, flowers, and their use as decoration. Nutritionally, they contribute with fibers, minerals, vitamins and carotenes, and have been, along with maize and beans, the base of many pre-Columbian cultures’ diets in the Americas [25]. As mentioned, it has been suggested that the genus was originally gathered for their gourds and consumption of their nutritious and palatable seeds [2,3]. The cultivated species are all annually herbaceous, with a great adaptation to diverse soils and climatic conditions, being grown from the tropic (C. moschata) to temperate-cold zones (C. maxima), and from sea level up to 2800 m.a.s.l. (C. ficifolia)[26]. The current genetic, biogeographical and archaeological data suggest that the cultivated forms are not derived from a common ancestor, whereas each species represents an independent domestication Diversity 2021, 13, 354 4 of 19

Diversity 2021, 13, 354 soils and climatic conditions, being grown from the tropic (C. moschata) to temperate‐cold4 of 19 zones (C. maxima), and from sea level up to 2800 m.a.s.l. (C. ficifolia) [26]. The current ge‐ netic, biogeographical and archaeological data suggest that the cultivated forms are not derived from a common ancestor, whereas each species represents an independent do‐ mesticationevent [27] (Figureevent [27]2). Except(Figure for 2). ExceptC. moschata for C.and moschataC. ﬁcifolia and, theC. ficifolia wild species, the wild from species which fromthey which were domesticatedthey were domesticated have been identiﬁedhave been [ 5identified,27–29]. [5,27–29].

FigureFigure 2. 2. DistributionDistribution map map of of wild wild species species of of CucurbitaCucurbita withwith occurrences occurrences based based on on 7000 7000 records records from from GBIFGBIF (www.gbif.org, (www.gbif.org ,accessed accessed on 15 NovemberNovember 2020).2020). Hypothesized Hypothesized origins origins of of domestication domestication for for the the five Cucurbita species are indicated by open circles. C pepo was split into the two cultivated spp. five Cucurbita species are indicated by open circles. C pepo was split into the two cultivated spp. C. C. pepo ssp. ovifera: dark green; C. pepo ssp. pepo: light green; C. argyrosperma ssp. argyrosperma: blue; pepo ssp. ovifera: dark green; C. pepo ssp. pepo: light green; C. argyrosperma ssp. argyrosperma: blue; C. C. moschata: magenta; C. ficifolia: light blue; C. maxima ssp. maxima: orange [30]. Copyright 2017 Else‐ moschata: magenta; C. ficifolia: light blue; C. maxima ssp. maxima: orange [30]. Copyright 2021 Kates, vier. Lopez-Anido, Sánchez-de la Vega, Eguiarte, Soltis and Soltis. In C. pepo, independent domestication events were proposed for the two cultivated In C. pepo, independent domestication events were proposed for the two cultivated subspecies (texana and pepo). The first one, in the southwestern USA related to the wild subspecies (texana and pepo). The first one, in the southwestern USA related to the wild ssp. ssp.texana texanavar. var.ozarkana ozarkana; the; second,the second, in Mexico, in Mexico, associated associated with with actual actual cultivated cultivated ornamental orna‐ mentalgourds gourds [28,31], [28,31], or to wild or to populations wild populations of C. pepo ofssp. C. pepofraterna ssp.[27 fraterna,32]. In [27,32].C. argyrosperma In C. argy, the‐ rospermawild ssp., thesororia wildis ssp. recognized sororia is as recognized the ancestor as of the cultivated ancestor forms, of cultivated presumably forms, domesticated presuma‐ blyin domesticated the lowlands ofin the Jalisco, lowlands Mexico of [Jalisco,29]. In MexicoC. moschata [29]., evenIn C. whenmoschata no, wildeven progenitorwhen no wild was progenitorfound, it is was believed found, that it is it believed could have that been it could domesticated have been either domesticated in northern either South in America, north‐ ernwhere South domesticated America, where forms domesticated of small fruits forms and of thicksmall fruitfruits shells and thick were fruit described, shells were or in described,Mexico, where or in theMexico, greatest where diversity the greatest of cultivated diversity forms of cultivated occurs [33]. forms The only occurs domesticated [33]. The onlyspecies domesticated of Cucurbita specieswith anof Cucurbita exclusively with South an exclusively American origin South is AmericanC. maxima origin; there is is C. no maximarecord; thatthere places is no record this species that places north ofthis the species equator north before of the the equator Spanish before colonization the Spanish of the colonizationAmericas [3 of]. Itthe had Americas a great importance [3]. It had a in great the pre-Incaimportance and in Inca the civilizations pre‐Inca and (Peru, Inca Boliviacivili‐ zationsand northwestern (Peru, Bolivia Argentina) and northwestern [34,35] where, Argentina) due to its [34,35] nutritional where, quality due to and its adaptation nutritional to qualitya temperate and adaptation climate, it gradually to a temperate replaced climate,C. moschata it graduallyand C. ficifolia replaced[24 ].C.C. moschata maxima wasand alsoC. ficifoliacultivated [24]. byC. maxima Arawak, was Guarani, also cultivated Qom and by Charrua Arawak, ethnics Guarani, in the Qom southeastern and Charrua Amazonas ethnics inriver the southeastern basin (including Amazonas northern river Bolivia basin and (including southeastern northern Brazil), Bolivia Paraguay, and southeastern northeastern Brazil),Argentina Paraguay, and the northeastern La Plata river Argentina basin (eastern and the Argentina La Plata and river Uruguay) basin (eastern [17,36 Argentina–39]. It was anddomesticated Uruguay) [17,36–39]. from the free It was living domesticated ssp. andreana fromsupposedly the free in living north-central ssp. andreana Argentina suppos and‐ edlyBolivia in north [2,17‐,central40]. Argentina and Bolivia [2,17,40].

2.2. Cucurbita Cucurbita Archeobotanics Archeobotanics 2.1.2.1. South South American American Archeological Archeological Sites Sites InIn South South America America the the longest longest lists lists of of crops crops domesticated domesticated origins origins are are from from areas areas where where goodgood conditions conditions exist exist for for archaeological archaeological artifact artifact preservation preservation and and where where complex complex societies societies with high population densities and advanced agricultural technologies existed (Inca and with high population densities and advanced agricultural technologies existed (Inca and pre-Inca civilizations in actual Peru, Bolivia, Northern Argentina) [41]. In Peru, on the pre‐Inca civilizations in actual Peru, Bolivia, Northern Argentina) [41]. In Peru, on the western slopes of the northern Andes, the earliest macrofossil remains of the Cucurbita sp. western slopes of the northern Andes, the earliest macrofossil remains of the Cucurbita sp. were dated 8435 ± 40 B.P. These are small seeds (6 to 7 mm long, 2.5 to 4 mm wide) of uniform dark brown color, prominent raised margins, and an elliptical shape [42]. These authors attributed these remains to C. moschata since a similar brown color and size seeds

were reported in Colombian landraces. However, C. maxima cannot be ruled out, since Diversity 2021, 13, 354 5 of 19

seed brown color cultivars are also common, as I will show below, in the Banana cultivar- group. In Amazonia, areas with higher population density in the pre-Columbian period also exhibited a rich crop genetic heritage, but the poor environments for archaeological preservation and lack of research effort have not yielded as much information [43]. The Amazon river basin has been highlighted as an important area of plant domestication and diversity associated with the swidden/fallow management, micro-environmental heterogeneity and small population sizes (genetic drift); moreover, the Beni savanna, which extends from northern Bolivia to Brazil and Peru, was proposed as a center of diversity for C. maxima and C. moschata [44]. In Cucurbita, phytoliths (microscopic structures made of silica persistent after plant decay) have been studied and evidence proven that domesticated forms were present on the northern South American lowlands’ landscape and tropical forest by at least 7000, and quite possibly by 9000 BP. The identiﬁcation of these microremains was referenced to the genus level (not species), and it was suggested that they could correspond either to C. moschata or C. maxima [45]. More recently Watling [38] found phytoliths of cultivated Cucurbita and possible wild Cucurbita at the Teotoni site (southwestern Amazonia), on the Madeira river, which its headwater comes from the Bolivian central Andes. The authors suggested that they may correspond to C. maxima, since as Whitaker and Cutler [3] stated, “The cultural history of the cucurbits indicates a very strong tendency towards conservative crop husbandry among pre-Columbian and post-Columbian peoples in that they tended to grow essentially the same cultivars over long periods of time”, and nowadays, C. maxima is most cultivated in the Brazilian Rodonia State (where the site is located). In northeastern Argentina, well-preserved seeds, rinds, peduncles and even entire fruits remains of domesticated and intermediate (semidomesticated) C. maxima were found in many sites, dated up to 2700 BP [34,46]. In the La Plata river basin lowlands, small-scale horticultural practices including Cucurbita were recorded in mounds distributed either in south-eastern Argentina and Uruguay but in a more recently time frame (2000 BP) associated with Guarani and possible Arawak cultures, both descendants from populations that originated in the amazon basin [39].

2.2. Diagnostic Macroremains The existence of a domestication relationship between ancient human societies and plant species can be inferred from morphological changes in the archaeological record of target plant populations [47]. In Cucurbita, the major archeological morphological diagnostic markers associated with domestication environments are an increase in seed, fruit and peduncle size and color changes in relation to the wild ancestor counterpart. In C. maxima, peduncles and seeds were proposed to be the best diagnostic archeological macrorest to identify Cucurbita spp., and the increase in their diameter and length, respectively, a good indicator of changes occurring under domestication [46]. C. maxima seeds are ﬂat, oval and with no pronounced marginal bulge; ssp. maxima (domesticated) can be white or brown; ssp. andreana is always light brown. Seeds between 13 and 30 mm long and 7–17 mm wide correspond to cultivated ssp. maxima, while seeds between 6.5 and 10 mm long and 4–6.5 mm wide to ssp. andreana. The peduncles of ssp. maxima can be distinguished from those of ssp. andreana by their basal diameter. Diameters less than, or equal to, 8 mm belong to the wild ancestor; meanwhile, diameters greater than or equal to 17 mm, to the domestic ssp. [46]. Fruit rind remains of both bottle gourds (L. siceraria) and Cucurbita are very commons in archeological sites [34]. In the case of Lagenaria, a substantial increase in rind thickness is associated with domesticated forms (fruit durability as containers) in contrast to the brittle and rapidly disintegrating exocarp of wild African counterparts [13]. Interestingly in the case of C. maxima, no clear association between rind thickness and cultivated remains was found [48]; this could be explained by the fact that cultivated forms for immature fruit consumption (summer squash) generally kept the thick exocarp of the wild ssp. along domestication, and the same was observed in C. pepo [49]. Diversity 2021, 13, 354 6 of 19

3. Cultivar-Groups The cultivar-group concept is a formal subspecific category for assembling cultivars on the basis of defined similarity [50]. In C. pepo, eight Cultivar-groups were proposed on the basis of fruit shape and length/width ratio; four belong to ssp. texana (Straightneck, Crookneck, Scallop and Acorn), and the remaining to ssp. pepo (Vegetable Marrow, Zucchini, Cocozelle and Pumpkin) [51]. In general, each cultivar-group is related to a distinct origin, i.e., Cocozelle appeared in Italy, where there is a preference for long immature fruits; Zucchini emerged at the USA market in the beginning of the last century, presumably derived from Cocozelle; Vegetable Marrow varieties, of a short tapered cylindrical fruit, were first developed in England in the 19th century; and the Acorn forms were raised by the Arikara Indians of North Dakota [52]. In C. moschata, Jeffrey [53] recognized that there is no wholly satisfactory subspecific classification, and, mainly based on geographical origin, proposed six cultivar-groups. Out of them, two assemblages of cultivars could be distinguished, the Caribbean-Colombian, related to short-day flowering requirements and in general brown seeds; and the Mexican, of long-day induction and light tan-colored seeds [54]. In C. maxima, a great variation of cultivated forms exists, and many attempts were conducted to classify them. Castetter [55], based in the cultivars of ample distribution among North American growers, proposed the first grouping of seven horticultural groups (Hub- bard, Delicious, Orange Marrows, Turban, Banana, Warty or Pebbled, Show or Display); however, the Zapallito type cultivars, of recognized importance as summer squash in the southern Latin American countries, were not included. Later, Grebencikov [56] considered a subspecific classification of six convarieties (Turbaniformis, Bananina, Hubbardiana, Maxima, Parvifructina and Zapallitina), which included the Zapallito type, but is not comprehensive regarding the cultivars forms that emerged in most seed catalogues since the last 60 years. Among these are the Nugget and Buttercup types in North America, New Zealand and Japan, and the Plomo and Moranga varieties in Argentina and Brazil. Moreover, the Zip- inca type, very popular in Northwestern Argentina local markets [36], was not considered. More recently, Goldman [57] presented a very nice pictured list of C. maxima cultivars, grouping them in Australian, Hubbard, Buttercup, Banana, Turban, Mammoth and Zapal- lito cultivar-groups. In the following, I will describe a comprehensive list, in which I merge previously separated groups and include new ones that deserve consideration.

3.1. Hubbard The Hubbard group or convariety Hubbardiana is characterized by its elliptical- acorn or ovate fruit shape, tapering curved to one or both ends, of medium to large size (2–6 kg). Rind color varies from green, blue-gray, orange to cream-white, with or without longitudinal stripes (Figure3). The rind surface is uneven to warted (generally not smooth). Flesh is orange-yellow with a good aptitude for mature fruits consumption. Plants show a viney growth habit; some new cultivars may be intermediate in internode length, as a semi-bush type and very few show mottled leaves. The Hubbard name was given in 1820 after a washerwomen of a sea captain who brought the seed from the West Indies [58]. I agree with [57] in including in this group the Delicious and Pebbled groups of [55].

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a dominant and recessive epistasis [60]. A distinguishing characteristic is that the ratio Diversity 2021, 13, 354 length to width of the seeds is the shortest of all cultivar-groups, ranging 1.4–1.5 [59].7 Theof 19

ﬁrst known illustration of a Turban fruits was drew by Nicolas Duchesne in 1785 [61]. Figure 3. Mature fruits from different accessions of C. maxima Hubbard Cultivar‐group. Public do‐ main photos, Germplasm Resources Information Network (GRIN), USA.

3.2. Turban The Turban group or convariety Turbaniformis is particular for its bizarre mature fruits where the pericarp does not enclose completely the fruit, leaving stylar tissue to come out as if one fruit was growing inside the other one (Figure 4). Fruits are generally medium to small in size, varying in rind color, with orange very frequent. Flesh may be light orange, yellow to cream, and some cultivars are not so good for mature consumption, rather sold for ornamental purpose. Plants have a viney growth habit with somehow smaller leaves than the rest of the cultivar‐groups, and long staminate flowers’ pedicels that make male flowers protrude over the foliage at anthesis [59]. Seeds are white; how‐ ever, some accessions are segregating for a brown seed coat, since its inheritance is com‐ plex, ruled by two loci with a dominant and recessive epistasis [60]. A distinguishing char‐ acteristic is that the ratio length to width of the seeds is the shortest of all cultivar‐groups, Figure 3. Mature fruits from different accessions of C. maxima Hubbard Cultivar‐group. Public do‐ Figureranging 3. 1.4–1.5Mature [59]. fruits The from first different known accessions illustration of C. of maxima a TurbanHubbard fruits Cultivar-group. was drew by Nicolas Public main photos, Germplasm Resources Information Network (GRIN), USA. domainDuchesne photos, in 1785 Germplasm [61]. Resources Information Network (GRIN), USA. 3.2. Turban The Turban group or convariety Turbaniformis is particular for its bizarre mature fruits where the pericarp does not enclose completely the fruit, leaving stylar tissue to come out as if one fruit was growing inside the other one (Figure 4). Fruits are generally medium to small in size, varying in rind color, with orange very frequent. Flesh may be light orange, yellow to cream, and some cultivars are not so good for mature consumption, rather sold for ornamental purpose. Plants have a viney growth habit with somehow smaller leaves than the rest of the cultivar‐groups, and long staminate flowers’ pedicels that make male flowers protrude over the foliage at anthesis [59]. Seeds are white; how‐ ever, some accessions are segregating for a brown seed coat, since its inheritance is com‐ plex, ruled by two loci with a dominant and recessive epistasis [60]. A distinguishing char‐ acteristic is that the ratio length to width of the seeds is the shortest of all cultivar‐groups,

ranging 1.4–1.5 [59]. The first known illustration of a Turban fruits was drew by Nicolas FigureDuchesneFigure 4.4. MatureMature in 1785 fruitsfruits [61]. fromfrom differentdifferent accessionsaccessions ofof TurbanTurban cultivar-group.cultivar‐group. BlueBlue rulerruler lengthlength 2020 cm.cm. SlicedSliced fruits,fruits, leftleft lightlight color color soft soft flesh, flesh,right rightmore more intense intense color color and and firm firm flesh. flesh.

3.3.3.3. BananaBanana TheThe BananaBanana groupgroup oror convarietyconvariety BananinaBananina isis characterized characterized byby its its elongated elongated medium medium sizesize maturemature fruits, with a a length length to to width width ratio ratio from from 2.3 2.3 to to 3.1 3.1 [59] [59 (Figure] (Figure 5),5 similar), similar to tothe theratio ratio of the of theVegetable Vegetable Marrow Marrow cultivar cultivar-group‐group of C. of pepoC. pepo[51].[ Fruits51]. Fruits have havegenerally generally three threestylar stylar locules locules (mean (mean 3.43). 3.43).Mature Mature fruit rind fruit color rind varies color as varies in the as Hubbard in the Hubbard group, group,but the butpink the is pinkmuch is more much frequent. more frequent. The flesh The color ﬂesh is colororange is orangewith a good with aaptitude good aptitude for mature for maturefruits consumption fruits consumption (winter (winter squash). squash). The presence The presence of a protuberance of a protuberance in the in stylar the stylar end end (nipple) and thick brown seeds are distinctive of the group [59]. Plants are of the viney type and leaves not mottled.

3.4. Show

The Show group also referenced as Display or Mammoth has been characterized by itsFigure big globular4. Mature maturefruits from fruits, different long accessions been known of Turban to produce cultivar the‐group. largest Blue fruit ruler inlength the plant20 cm. kingdomSliced fruits, (Figure left light6). Interestcolor soft in flesh, large right pumpkins more intense derives color from and exhibitsfirm flesh. in agricultural fairs either in North American or European rural life since the last 150 years [62]. Rind color is3.3. generally Banana orange, yellow or cream. Flesh color is light orange, yellow or even cream, with poorThe Banana quality group for consumption or convariety as winterBananina squash, is characterized ﬂesh dry matter by its elongated between 4.3% medium and 5.1%size mature [59]. Seeds’ fruits, length with a to length width to ratio width of ratio this group from 2.3 is aboveto 3.1 [59] 1.8, (Figure being the 5), highest similar ofto the all ratio of the Vegetable Marrow cultivar‐group of C. pepo [51]. Fruits have generally three stylar locules (mean 3.43). Mature fruit rind color varies as in the Hubbard group, but the pink is much more frequent. The flesh color is orange with a good aptitude for mature fruits consumption (winter squash). The presence of a protuberance in the stylar end

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(nipple) and thick brown seeds are distinctive of the group [59]. Plants are of the viney type and leaves not mottled.

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C. maxima cultivar-groups; similar results were found for the globular Pumpkin cultivar- group(nipple) of C.and pepo thick[63 ].brown Plants seeds are viney; are distinctive some cultivars of the bear group yellow [59]. stems Plants [64 are], andof the mottled viney leavestype and are leaves absent. not mottled.

Figure 5. Mature fruits from different accessions of C. maxima Banana cultivar‐group. Blue ruler 20 cm. Sliced fruit bearing three locules.

3.4. Show The Show group also referenced as Display or Mammoth has been characterized by its big globular mature fruits, long been known to produce the largest fruit in the plant kingdom (Figure 6). Interest in large pumpkins derives from exhibits in agricultural fairs either in North American or European rural life since the last 150 years [62]. Rind color is generally orange, yellow or cream. Flesh color is light orange, yellow or even cream, with poor quality for consumption as winter squash, flesh dry matter between 4.3 and 5.1% [59]. Seeds’ length to width ratio of this group is above 1.8, being the highest of all C. maxima cultivar‐groups; similar results were found for the globular Pumpkin cultivar‐ FigureFigure 5.5. Mature fruits from different different accessions accessions of of C.C. maxima maxima BananaBanana cultivar cultivar-group.‐group. Blue Blue ruler ruler 20 groupcm. Sliced of C. fruit pepo bearing [63]. Plantsthree locules. are viney; some cultivars bear yellow stems [64], and mottled 20leaves cm. Sliced are absent. fruit bearing three locules. 3.4. Show The Show group also referenced as Display or Mammoth has been characterized by its big globular mature fruits, long been known to produce the largest fruit in the plant kingdom (Figure 6). Interest in large pumpkins derives from exhibits in agricultural fairs either in North American or European rural life since the last 150 years [62]. Rind color is generally orange, yellow or cream. Flesh color is light orange, yellow or even cream, with poor quality for consumption as winter squash, flesh dry matter between 4.3 and 5.1% [59]. Seeds’ length to width ratio of this group is above 1.8, being the highest of all C. maxima cultivar‐groups; similar results were found for the globular Pumpkin cultivar‐ group of C. pepo [63]. Plants are viney; some cultivars bear yellow stems [64], and mottled

leaves are absent. FigureFigure 6.6. RightRight,, fruitsfruits ofof ShowShow cultivar-groupcultivar‐group atat BarnesvilleBarnesville PumpkinPumpkin FestivalFestival inin Barnesville,Barnesville, Ohio,Ohio, USA,USA, picture picture credit credit Lee Lee Paxton Paxton (https://en.wikipedia.org/wiki/User:Leepaxton (https://en.wikipedia.org/wiki/User:Leepaxton,, accessed onon 1515 June June 2021). Left, world records of pumpkin fruit weight [65]. 2021). Left, world records of pumpkin fruit weight [65].

3.5.3.5. ButtercupButtercup TheThe ButtercupButtercup cultivar-groupcultivar‐group isis characterizedcharacterized byby itsits medium-smallmedium‐small sizesize (1.6–1.7(1.6–1.7 kg),kg), ﬂattenedflattened transversetransverse broadbroad elliptic-rectangularelliptic‐rectangular shape.shape. Rind color isis darkdark green,green, withwith oror withoutwithout lightlight greengreen stripes.stripes. PericarpPericarp maymay incompletelyincompletely encompassencompass thethe fruitfruit showingshowing aa smallsmall crowncrown inin thethe stylarstylar endend (Figure(Figure7 ).7). Flesh Flesh is is orange orange with with a a good good quality quality for for mature mature consumption,consumption, sweetness sweetness and and nutty nutty ﬂavor flavor [ [66].66]. This This group group is is very very popular popular in in New New Zealand Zealand and Japan (known as Kabocha). Plants are semi-bush with an intermediate internode and Japan (known as Kabocha). Plants are semi‐bush with an intermediate internode length,length, andand mottledmottled leavesleaves absent.absent. Figure 6. Right, fruits of Show cultivar‐group at Barnesville Pumpkin Festival in Barnesville, Ohio, 3.6.USA, Nugget picture credit Lee Paxton (https://en.wikipedia.org/wiki/User:Leepaxton, accessed on 15 June 2021). Left, world records of pumpkin fruit weight [65]. The Nugget is a relatively new group, commonly sold nowadays in United States

vegetable3.5. Buttercup seeds companies. The precocious bicolor fruit attribute is characteristic of the group, which gives a bright yellow color when immature, turning to orange when ripe (FigureThe8). Buttercup Fruits are cultivar ﬂat-globular‐group inis characterized shape and intermediate by its medium to small‐small in size size, (1.6–1.7 same kg), as Buttercup.flattened transverse Flesh is orange,broad elliptic suitable‐rectangular for mature shape. consumption Rind color as is winter dark green, squash. with The or presencewithout oflight a nipple green as stripes. in the BananaPericarp cultivar-group may incompletely is very encompass frequent. Plants the fruit are semi-bush,showing a asmall characteristic crown in also the pursuedstylar end in modern(Figure 7).C. pepoFleshand is orangeC. moschata withcultivars a good quality for its amenability for mature toconsumption, high-density sweetness planting and [24]. nutty Mottled flavor leaves [66]. This in the group foliage is very are popular absent. in Goldman New Zealand [57] includedand Japan the (known nugget typeas Kabocha). in the zapallito Plants group, are semi but as‐bush I show with below an intermediate they are quite internode different. length, and mottled leaves absent.

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Figure 7. Fruits of Buttercup cultivar‐group, left unripe fruit in plant, right, mature fruits, one up‐ side‐down showing the crown. Blue ruler 20 cm.

3.6. Nugget The Nugget is a relatively new group, commonly sold nowadays in United States vegetable seeds companies. The precocious bicolor fruit attribute is characteristic of the group, which gives a bright yellow color when immature, turning to orange when ripe (Figure 8). Fruits are flat‐globular in shape and intermediate to small in size, same as But‐ tercup. Flesh is orange, suitable for mature consumption as winter squash. The presence of a nipple as in the Banana cultivar‐group is very frequent. Plants are semi‐bush, a char‐ acteristic also pursued in modern C. pepo and C. moschata cultivars for its amenability to Figure 7. Fruits of Buttercup cultivar‐group, left unripe fruit in plant, right, mature fruits, one up‐ Figurehigh‐density 7. Fruits planting of Buttercup [24]. Mottled cultivar-group, leaves inleft theunripe foliage fruit are in absent. plant, rightGoldman, mature [57] fruits, included one side‐down showing the crown. Blue ruler 20 cm. upside-downthe nugget type showing in the the zapallito crown. Blue group, ruler but 20 cm.as I show below they are quite different. 3.6. Nugget The Nugget is a relatively new group, commonly sold nowadays in United States vegetable seeds companies. The precocious bicolor fruit attribute is characteristic of the group, which gives a bright yellow color when immature, turning to orange when ripe (Figure 8). Fruits are flat‐globular in shape and intermediate to small in size, same as But‐ tercup. Flesh is orange, suitable for mature consumption as winter squash. The presence of a nipple as in the Banana cultivar‐group is very frequent. Plants are semi‐bush, a char‐ acteristic also pursued in modern C. pepo and C. moschata cultivars for its amenability to high‐density planting [24]. Mottled leaves in the foliage are absent. Goldman [57] included the nugget type in the zapallito group, but as I show below they are quite different.

FigureFigure 8.8. Upper row,row, maturemature entireentire andand slicedsliced fruitsfruits ofof NuggetNugget cultivar-group.cultivar‐group. Blue rulerruler 2020 cm.cm. LowerLower row,row, typical typical semi-bush semi‐bush plant plant bearing bearing immature immature fruits. fruits.

3.7.3.7. ZapallitoZapallito ZapalloZapallo isis thethe QuechuaQuechua languagelanguage wordword referring referring to to pumpkin. pumpkin. Zapallito Zapallito is is thethe SpanishSpanish diminutivediminutive formform ofof ZapalloZapallo (small(small pumpkin).pumpkin). TheThe ZapallitoZapallito cultivar-groupcultivar‐group oror convarietyconvariety ZapallitinaZapallitina isis onlyonly growngrown forfor thethe consumptionconsumption ofof thethe immatureimmature fruitsfruits asas summer summer squashsquash (Figure(Figure9 9).). The market bright bright light light green green color color size size fruit fruit is reached, is reached, depending depending on air on tem air ‐ temperature,perature, between between six up six to up ten to days ten days after after anthesis anthesis (daa); (daa); it takes it takes longer longer than thanC. pepoC. sum pepo‐ summer squash that generally are harvested between 2 and 3 daa. This could be due mer squash that generally are harvested between 2 and 3 daa. This could be due to the tosmaller the smaller ovary of ovary pistillate of pistillate flowers flowersat anthesis at anthesis of C. maxima of C. in maxima comparisonin comparison to C. pepo. to MaC.‐ Figure 8. Upper row, mature entire and sliced fruits of Nugget cultivar‐group. Blue ruler 20 cm. pepoture. fruits Mature are fruits flattened, are flattened, with a length with to a width length ratio to width ranging ratio 0.6–0.7; ranging rinds 0.6–0.7; are dark rinds green are Lower row, typical semi‐bush plant bearing immature fruits. darkturning green brown, turning and brown, may show and maya small show crown a small in the crown stylar in end, the stylar same end,as in same the Buttercup as in the Buttercup cultivar-group. Mature fruit flesh is light orange, yellow or cream, with very cultivar3.7. Zapallito‐group. Mature fruit flesh is light orange, yellow or cream, with very poor quality poorfor consumption quality for consumption as winter squash as winter (flesh squash dry matter (flesh 4.9–5.5%). dry matter In 4.9–5.5%). fact, mature In fact, fruits mature have Zapallo is the Quechua language word referring to pumpkin. Zapallito is the Spanish fruitsa very have short a very shelf short‐life. shelf-life.Plants are Plants bush are type, bush with type, the with shortest the shortest internode internode length length of all ofdiminutive all cultivar-groups form of Zapallo (11–20 mm), (small and pumpkin). mottled leavesThe Zapallito very rare. cultivar Seeds‐ aregroup white. or convariety I consider thatZapallitina varieties is includedonly grown as Zapallitofor the consumption by Goldman of [57 the] are immature not accurately fruits as assigned; summer one squash is a Nugget(Figure type9). The and market the other bright (SilverBell) light green is acolor small size Hubbard fruit is type.reached, depending on air tem‐ perature, between six up to ten days after anthesis (daa); it takes longer than C. pepo sum‐ mer squash that generally are harvested between 2 and 3 daa. This could be due to the smaller ovary of pistillate flowers at anthesis of C. maxima in comparison to C. pepo. Ma‐ ture fruits are flattened, with a length to width ratio ranging 0.6–0.7; rinds are dark green turning brown, and may show a small crown in the stylar end, same as in the Buttercup cultivar‐group. Mature fruit flesh is light orange, yellow or cream, with very poor quality for consumption as winter squash (flesh dry matter 4.9–5.5%). In fact, mature fruits have a very short shelf‐life. Plants are bush type, with the shortest internode length of all

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Diversity 2021, 13, 354 cultivar‐groups (11–20 mm), and mottled leaves very rare. Seeds are white. I consider10 of that 19 varieties included as Zapallito by Goldman [57] are not accurately assigned; one is a Nug‐ get type and the other (SilverBell) is a small Hubbard type.

FigureFigure 9. 9. UpperUpper row,row, Zapallito Zapallito cultivar-group cultivar‐group bush bush plant plant at at anthesis anthesis and and bucket bucket at at harvest. harvest. Lower Lower row, entire and sliced mature fruits bearing typical thin spongy light colored flesh. Blue ruler length row,row, entire entire and and sliced sliced mature mature fruits fruits bearing bearing typical typical thin thin spongy spongy light light colored colored ﬂesh. flesh. Blue Blue ruler ruler length length 20 cm. 20 cm.

3.8.3.8. PlomoPlomo ThisThis cultivar-groupcultivar‐group isis characterizedcharacterized byby medium-largemedium‐large globularglobular oror flatted flatted grey-blue grey‐blue lobedlobed fruitsfruits (Figure(Figure 1010).). PlomoPlomo inin SpanishSpanish meansmeans lead,lead, forfor thethe particularparticular greygrey color. color. InIn Brazil,Brazil, theythey areare knownknown asas “Ab“Abóboraóbora gagaúcha”úcha” [67[67].]. InIn Spain,Spain, theythey areare calledcalled Valencia’sValencia’s squash.squash. II considerconsider thatthat itit belongsbelongs toto thethe PlomoPlomo cultivar-group,cultivar‐group, the the Australian-blue Australian‐blue group group ofof [[57].57]. In In Italy, Italy, the the popular popular variety variety Marina Marina di Chioggia di Chioggia is also is also representative representative of this of culti this‐ cultivar-groupvar‐group and and was was depicted depicted in eighteenth in eighteenth century century drawings drawings [61]. [61 Fruits]. Fruits are are excellent excellent as aswinter winter squash squash owing owing to their to their meaty meaty and anddeep deep orange orange flesh. flesh. In Australia In Australia and South and Africa, South Africa,many improved many improved cultivars cultivars have been have developed, been developed, some of some them of with them virus with resistance virus resistance trans‐ transferredferred from from C. ecuadorensisC. ecuadorensis alongalong backcrosses backcrosses and selfings and selfings [68]. Plants [68]. Plants are viney, are viney, and mott and‐ mottledled leaves leaves can be can found be found in some in some cultivars. cultivars. Seeds Seeds could could be either be either brown brown or white. or white.

FigureFigure 10. 10. FruitsFruits ofof PlomoPlomo cultivar-group.cultivar‐group. LowerLower row,row, left left globular, globular, right right ﬂattened flattened type. type. Blue Blue ruler ruler lengthlength 20 20 cm. cm.

3.9. Moranga C. maxima cultivars grown in Brazil have rarely been included in descriptions. Moranga means squash in Portuguese, and the characteristic of this cultivar-group deserves, in my opinion, its inclusion. Fruits are orange with light colored stripes, medium to large size (3.7–5.3 kg), ﬂattened, with marked lobes and between 4–5 locules (Figure 11). Flesh is light

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3.9. Moranga 3.9. MorangaC. maxima cultivars grown in Brazil have rarely been included in descriptions. Mo‐ Diversity 2021, 13, 354 rangaC. means maxima squash cultivars in Portuguese, grown in Brazil and the have characteristic rarely been of included this cultivar in descriptions.‐group deserves,11 ofMo 19‐ inranga my meansopinion, squash its inclusion. in Portuguese, Fruits are and orange the characteristic with light colored of this cultivarstripes, ‐mediumgroup deserves, to large sizein my (3.7–5.3 opinion, kg), its flattened, inclusion. with Fruits marked are orange lobes withand betweenlight colored 4–5 loculesstripes, (Figure medium 11). to Fleshlarge sizeis light (3.7–5.3 orange, kg), with flattened, an aptitude with marked for mature lobes consumption. and between 4–5Plants locules are viney,(Figure and 11). leaves Flesh orange,nonis light‐mottled. withorange, an Seeds aptitude with can an be foraptitude brown mature orfor consumption. white mature [59]. consumption. Plants are viney, Plants and are leaves viney, non-mottled. and leaves Seedsnon‐mottled. can be brown Seeds orcan white be brown [59]. or white [59].

Figure 11. Fruits of Moranga cultivar‐group, lower row, sliced fruit showing five locules. Blue ruler FigureFigurelength 11.2011. cm. FruitsFruits ofof Moranga cultivar-group,cultivar‐group, lowerlower row,row, sliced sliced fruit fruit showing showing five five locules. locules. Blue Blue ruler ruler lengthlength 2020 cm.cm. 3.10. Zipinka 3.10.3.10. ZipinkaTheZipinka word Zipinka comes from the Quechua language Sip’u that means warts. ZipinkaTheThe cultivar wordword Zipinka ‐Zipinkagroup comes fruits comes fromare from acorn the Quechuathe shaped, Quechua language small language (0.7–1.3Sip’u that kg),Sip’u meanswith that abundant warts. means Zipinka warts.warts cultivar-groupZipinkawhen ripe; cultivar color fruits‐ groupvaries are from acornfruits brown,are shaped, acorn dark small shaped, green (0.7–1.3 smallto grey kg), (0.7–1.3 with(Figure abundant kg), 12). with It is warts abundantdistinguishable when warts ripe; colorwhenby their varies ripe; hard color from thick brown,varies rind from dark(2.6–3.5 brown, green mm), to dark greyby fargreen (Figure the tothickest 12grey). It (Figure isrinds distinguishable of 12). all It cultivar is distinguishable by‐groups their hard in‐ thickcludingby their rind thehard (2.6–3.5 wild thick ssp. mm), rind andreana by (2.6–3.5 far the[59]. mm), thickest The by orange far rinds the flesh of thickest all is cultivar-groups meaty rinds but of thin, all includingcultivar with a ‐prettygroups the wild high in‐ ssp.cludingdry andreanamatter the (9.6–9.8%).wild[59]. ssp. The andreana orangePlants are flesh[59]. semi The is meaty‐bush orange with but flesh thin, an isinternode with meaty a pretty but length thin, high between with dry a matter pretty 33 and (9.6–high 67 9.8%).mm,dry matter and Plants mottled (9.6–9.8%). are semi-bush leaves Plants are with quite are an semi frequent. internode‐bush Another with length an betweenparticularinternode 33 characteristiclength and 67 between mm, and of 33this mottled and culti 67‐ leavesmm,var‐group and are mottled quiteis the frequent.amount leaves areof Another seeds quite produced,frequent. particular Another between characteristic particular 8200 and of thischaracteristic9900 cultivar-group seeds per of m this2. Whita is culti the‐ 2 amountkervar ‐andgroup ofCutler seedsis the [3] produced,amount argued ofthat betweenseeds in Cucurbita produced, 8200 and, this between 9900 attribute seeds 8200 was per and related m 9900. Whitaker to seeds primitive per and m Cutler varieties,2. Whita [3]‐ arguedkeroriginally and that Cutler selected in Cucurbita [3] argued for ,the this that consumption attribute in Cucurbita was related,of this both attribute to flesh primitive wasand relatedseeds. varieties, toMillán primitive originally [17] varieties,included selected forZipinkaoriginally the consumption in selectedthe Zapallito for of boththe group, consumption flesh but and even seeds. whenof Millboth theán flesh [fruits17] includedand are seeds.small, Zipinka fruitsMillán inand [17] the plant Zapallitoincluded habit group,Zipinkaare quite but in different. eventhe Zapallito when the group, fruits arebut small,even when fruits the and fruits plant are habit small, are quitefruits different. and plant habit are quite different.

FigureFigure 12.12. FruitsFruits ofof ZipinkaZipinka cultivar-group.cultivar‐group. Lower row,row, leftleft,, slicedsliced maturemature fruit;fruit; rightright,, seeds seeds and and fleshFigureflesh werewere 12. removed removedFruits of to Zipinkato show show thick thickcultivar rind. rind.‐group. Blue Blue ruler rulerLower length length row, 20 20left cm. cm., sliced mature fruit; right, seeds and flesh were removed to show thick rind. Blue ruler length 20 cm. 4. Diversity and Domestication Pathways In C. maxima, a couple studies have been conducted in order to elucidate genetic relationships among cultivars or accessions, but neither was comprehensive to include as many cultivar-groups as described above nor was the ssp. andreana considered. Ferriol [69] studied fifty landraces mostly collected in Spain, and nine from South American origin. They used SRAP (sequenced related amplified polymorphism) and AFLP (amplified fragment Diversity 2021, 13, 354 12 of 19

4. Diversity and Domestication Pathways In C. maxima, a couple studies have been conducted in order to elucidate genetic re‐ lationships among cultivars or accessions, but neither was comprehensive to include as Diversity 2021, 13, 354 many cultivar‐groups as described above nor was the ssp. andreana considered. Ferriol12 of 19 [69] studied fifty landraces mostly collected in Spain, and nine from South American origin. They used SRAP (sequenced related amplified polymorphism) and AFLP (ampli‐ fied fragment length polymorphism) markers, obtaining 50 and 145 polymorphic frag‐ length polymorphism) markers, obtaining 50 and 145 polymorphic fragments, respectively. ments, respectively. Principal coordinate analysis (PCoA) were advanced, where SRAP Principal coordinate analysis (PCoA) were advanced, where SRAP markers differentiated markers differentiated accessions in relation to fruit attributes (flesh color and shape), accessions in relation to fruit attributes (flesh color and shape), those for cattle feeding those for cattle feeding (globular with light colored flesh), human consumption (flattened (globular with light colored flesh), human consumption (flattened to globular with orange to globular with orange flesh) and turban type. Meanwhile AFLP separated mainly in flesh) and turban type. Meanwhile AFLP separated mainly in relation to provenances relation(America to vs.provenances Spain), and (America then, within vs. Spain), the Spanish, and then, human within consumption the Spanish, from human cattle feeding con‐ sumption(Figure 13 from). cattle feeding (Figure 13).

FigureFigure 13. 13. RelationshipsRelationships among among 38 38accessions accessions of C. of maximaC. maxima usingusing AFLP AFLP markers markers based based on Dice on dis Dice‐ tance.distance. Bootstrap Bootstrap values values are indicated. are indicated. Entry Entry codes codes beginning beginning with PER, with PER,ARG, ARG, BOL, BOL,ECU, ECU,OCE and OCE AFRand are AFR from are Peru, from Peru,Argentina, Argentina, Bolivia, Bolivia, Ecuador, Ecuador, New Zealand New Zealand and Morocco, and Morocco, respectively. respectively. The rest The ofrest the of entries the entries are from are fromSpain. Spain. Adapted Adapted from [69]. from [69].

KazminskaKazminska [70] [70 ]surveyed surveyed 85 85 C.C. maxima maxima cultivatedcultivated accessions accessions from from Europe, Europe, North North America,America, Asia, Asia, Australia Australia and and New New Zealand, Zealand, which which include include representatives representatives of of six six cultivar cultivar-‐ groups.groups. They They used used 23 23 simple simple sequence sequence repeat repeat markers markers (SSR) (SSR) that that generated generated 99 99 alleles. alleles. ClusterCluster analysis analysis was was advanced advanced in which in which one one major major cluster cluster comprised comprised accessions accessions from from Ba‐ nana,Banana, Buttercup Buttercup and and Hubbard Hubbard cultivars cultivars-groups.‐groups. The The second second major major cluster cluster was was divided divided in in twotwo sub sub-clusters,‐clusters, one one of of which includedincluded mostlymostly cultivars cultivars from from the the USA USA and and western western Europe Eu‐ ropeof the of Showthe Show cultivar-group, cultivar‐group, and the and second the second comprised comprised old cultivars old cultivars from central from central and eastern and easternEurope Europe not assigned not assigned with any with cultivar-group. any cultivar‐group. A third A minor third minor cluster cluster was distinguished, was distin‐ guished,more outlying, more outlying, that involved that twoinvolved accessions two ofaccessions the Australian of the Blue Australian cultivar-group Blue cultivar (Plomo),‐ groupone representative (Plomo), one representative of the Turban cultivar-group of the Turban andcultivar a Ukrainian‐group and provenance. a Ukrainian The prove mean‐ nance.distance The among mean distance the 85 accessions among the of 85C. accessions maxima was of C. 0.56. maxima PCoA was was 0.56. advanced PCoA was only ad for‐ vancedthe modern only for cultivars, the modern and divided cultivars, the and accessions divided into the threeaccessions groups into [70 three] (Figure groups 14). [70] One (Figureincluded 14). accessions One included from accessions the Banana, from Hubbard the Banana, and Buttercup Hubbard cultivar-groups. and Buttercup cultivar Another‐ comprised five entries from the Show cultivar-group, and the third consisted of three groups. Another comprised five entries from the Show cultivar‐group, and the third con‐ cultivars from the Australian Blue cultivar-group (Plomo) [70]. sisted of three cultivars from the Australian Blue cultivar‐group (Plomo) [70]. I conducted a study including 159 entries of C. maxima covering entries from all cultivar-groups above described with wild ssp. andreana provenances and out-groups from C. ecuadorensis, C. moschata, C. ficifolia and cultivated C. argyrosperma [59]. The evaluation was conducted along two seasons for morphological descriptors of leaf, stem, flower, fruit, seed [71,72]. In a subset of 78 accessions, a molecular analysis was conducted along SRAP markers, which yielded 208 polymorphic bands. In Figure 15 is presented the hierarchical cluster analysis dendrogram. Diversity 2021, 13, 354 13 of 19

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Figure 14. PcoA grouping results obtained with the distance matrix for C. maxima cultivars; color circles indicate three clusters of cultivars [70]. Cultivar‐groups after [57]. Copyright 2021 Kates, Lopez‐Anido, Sánchez‐de la Vega, Eguiarte, Soltis and Soltis.

I conducted a study including 159 entries of C. maxima covering entries from all cul‐ tivar‐groups above described with wild ssp. andreana provenances and out‐groups from C. ecuadorensis, C. moschata, C. ficifolia and cultivated C. argyrosperma [59]. The evaluation was conducted along two seasons for morphological descriptors of leaf, stem, flower, fruit, seed [71,72]. In a subset of 78 accessions, a molecular analysis was conducted along

SRAP markers, which yielded 208 polymorphic bands. In Figure 15 is presented the hier‐ Figure 14.archicalPcoAFigure grouping 14.cluster PcoA resultsanalysis grouping obtained dendrogram. results with obtained the distance with the matrix distance for C.matrix maxima for cultivars;C. maxima color cultivars; circles color indicate three clusters of cultivarscircles indicate [70]. Cultivar-groups three clusters afterof cultivars [57]. Copyright [70]. Cultivar 2017 Elsevier.‐groups after [57]. Copyright 2021 Kates, Lopez‐Anido, Sánchez‐de la Vega, Eguiarte, Soltis and Soltis.

Figure 15.FigureHierarchical 15. Hierarchical cluster dendrogram cluster dendrogram of 78 Cucurbita of accessions78 Cucurbita for accessions SRAP markers for polymorphisms.SRAP markers polymor Unbiased‐ p-values for multiscalephisms. bootstrap Unbiased resampling p‐values are for showed multiscale in some bootstrap branching. resampling For entries, are showed a tripartite in abbreviationsome branching. code For was used, in which theentries, number a is tripartite a household abbreviation accession code code was (see supplementaryused, in which Tablethe number S1 for details); is a household uppercase accession letter refers code to species other than(seeC. maxima supplementaryor cultivar-group Table S1 in forC. maximadetails);,F( uppercaseC. ﬁcifolia ),letter Y (C. refers argyrosperma to species), C other (C. moschata than C.), Rmaxima (C. ecuadorensis or ), A (ssp. andreana), B (Buttercup), P (Plomo), M (Moranga), Z (Zapallito), T (Turban), S (Show), H (Hubbard), K (Zipinka), L (Banana), N (Nugget). When C. maxima accessions could not be assigned to any cultivar-group, uppercase letter is missing. The rest of the lower case letters in the code refers to country of origin us (USA), ar (Argentina), pe (Peru), br (Brazil), ch (Chile), bo (Bolivia), pa (Paraguay), ur (Uruguay), ec (Ecuador), mx (Mexico), sp (Spain), it (Italy), hu (Hungary), au

(Australia), so (South Africa) and unk (not speciﬁed in passport data). For Argentinian entries of ssp. Andreana, lowercase letters indicateFigure Province 15. Hierarchical of origin, st cluster (Santiago dendrogram del Estero), of co 78 (C Cucurbitaórdoba), eraccessions (Entre R íforos), SRAP sl (San markers Luis) and polymor ba (Buenos‐ Aires). phisms. Unbiased p‐values for multiscale bootstrap resampling are showed in some branching. For entries, a tripartite abbreviation code was used, in which the number is a household accession code (see supplementary Table S1 for details); uppercase letter refers to species other than C. maxima or

Diversity 2021, 13, 354 14 of 19

cultivar‐group in C. maxima, F (C. ficifolia), Y (C. argyrosperma), C (C. moschata), R (C. ecuadorensis), A (ssp. andreana), B (Buttercup), P (Plomo), M (Moranga), Z (Zapallito), T (Turban), S (Show), H (Hub‐ bard), K (Zipinka), L (Banana), N (Nugget). When C. maxima accessions could not be assigned to any cultivar‐group, uppercase letter is missing. The rest of the lower case letters in the code refers to country of origin us (USA), ar (Argentina), pe (Peru), br (Brazil), ch (Chile), bo (Bolivia), pa (Par‐ aguay), ur (Uruguay), ec (Ecuador), mx (Mexico), sp (Spain), it (Italy), hu (Hungary), au (Australia), Diversity 2021, 13, 354 so (South Africa) and unk (not specified in passport data). For Argentinian entries of ssp. Andreana14 of 19 , lowercase letters indicate Province of origin, st (Santiago del Estero), co (Córdoba), er (Entre Ríos), sl (San Luis) and ba (Buenos Aires).

InIn the the cluster cluster analysis analysis of of Figure Figure 15 15,, the the out-group out‐groupCucurbita Cucurbitaspecies species were were clearly clearly sepa- sep‐ rated.arated. Subspecies Subspeciesandreana andreanaentries entries were were also disjointed,also disjointed, but interestingly but interestingly accession accession 129unk (MAX129unk 24 (MAX from 24 IPK from Genebank, IPK Genebank, Gatersleben, Gatersleben, Germany) Germany) clustered clustered with the with ssp. theandreana ssp. an‐ entries.dreana entries. The accession The accession name isname “Ovo is de “Ovo Ganso” de Ganso” (meaning (meaning goose´ sgoose´s egg in egg Portuguese), in Portu‐ andguese), even and when even in when the IPK in the Genebank IPK Genebank passport passport data are data referred are referred as unknown as unknown origin, itorigin, was donatedit was donated by the Agronomicby the Agronomic Institute Institute of Campinas, of Campinas, Brazil. ThisBrazil. entry This was entry included was included in the parvifructinain the parvifructinaconvariety convariety along along with wild with ssp. wildandreana ssp. andreanaand pictured and pictured by [56 by]. [56]. Remarkably Remark‐ 129unkably 129unk produce produce very smallvery small pink-grey pink‐ butgrey not but bitter not bitter fruits fruits (Figure (Figure 16). Flesh 16). Flesh is orange is orange and thin,and thin, and fruitand fruit weight weight and peduncleand peduncle width width are not are significant not significant different different from from those those of ssp. of andreanassp. andreana[59]; [59]; seeds seeds are are white, white, intermediate intermediate in in length length between between the the cultivar-group cultivar‐group with with thethe smallestsmallest seeds (Zipinka) and and ssp. ssp. andreanaandreana; and; and do do not not have have dormancy dormancy as asreported reported for forssp. ssp. andreanaandreana [73].[ 73Unusually,]. Unusually, dry matter dry matter content content is very is high very (13.25%). high (13.25%). The plant The habit plant is habitviney, is and viney, it took and to it tookonset to pistillate onset pistillate anthesis anthesis 25 more 25 days more than days ssp. than andreana ssp. andreana as a wholeas ◦ 0 awhen whole grown when at grown latitude at 33°1 latitude′ S. It 33is clear1 S. that It is it clear has short that it‐day has floral short-day induction, floral as induction, Cucurbita asprovenancesCucurbita provenances from low latitudes. from low Hammer latitudes. and Hammer Gladis [74] and mentioned Gladis [74] within mentioned the convari within‐ theety convarietyparvifructinaparvifructina the presencethe of presence a small‐fruited, of a small-fruited, non‐bitter, non-bitter,trailing form trailing with hard form shells with hardwide shells‐spread wide-spread in Brazil. In in [67], Brazil. fruits In [resembling67], fruits resembling those of 129unk those ofare 129unk pictured are as pictured ornamen as‐ ornamentaltal gourds with gourds edible with flesh edible cultivated flesh cultivated in Brazil. in Brazil.

FigureFigure 16. 16. MatureMature entireentire and and sliced sliced fruits fruits of of Ovo Ovo de de Ganso Ganso (MAX (MAX 24, 24, IPK IPK Genebank, Genebank, Gatersleben, Gatersleben, Germany).Germany). BlueBlue rulerruler length length 20 20 cm. cm.

Moreover,Moreover, within within ssp. ssp.andreana andreana, provenances, provenances from from the Santiagothe Santiago del Estero del Estero province province were differentiatedwere differentiated from thosefrom those of Cordoba, of Cordoba, Entre Entre Rios andRios Buenos and Buenos Aires Aires provinces provinces (Figure (Figure 15). Within15). Within the domesticated the domesticatedC. maxima C. maxima, a sub-cluster, a sub‐cluster with with a 96a 96 bootstraps bootstraps was was composed composed byby ButtercupButtercup accessionsaccessions 56Bsd56Bsd (PI(PI 234608 234608 Queensland Queensland BlueBlue fromfrom GRIN GRIN Genebank, Genebank, USA)USA) andand 3Bar,3Bar, and and the the Chilean Chilean 1ch. 1ch. Interestingly,Interestingly, inin the the study study of of [ 70[70],], the the same same Queensland Queensland BlueBlue alongalong with other other Buttercup Buttercup accessions accessions conformed conformed the the most most distant distant cluster cluster of the of the do‐ domesticates.mesticates. For For the the rest rest of ofthe the accessions, accessions, there there was was not not a clear a clear clustering clustering in inrelation relation to tocultivar cultivar-group‐group belonging; belonging; meanwhile, meanwhile, some some entries entries with with a common a common origin origin clustered clustered to‐ together.gether. One One particular particular point point that that was was resolved resolved is is referred toto accessionaccession 198us198us (PI(PI 165558 165558 fromfrom India) India) which which has has been been long long included included in in the the Gene Gene List List of ofCucurbita Cucurbita[ [49]49] as as a a donor donor of of thethe BicolorBicolor precociousprecocious yellowyellow fruit fruit pigmentation pigmentation ( B(Bmaxmax), which isis true,true, butbut isis referredreferred as as ssp. Andrena; however, it clustered within the domesticated, has a medium size fruit and has a lack of seed dormancy, so it is clearly not ssp. andreana (Figure 14). Kates [40], using ~15,000 single nucleotide polymorphisms (SNPs), evaluated 32 improved and landraces entries of C. maxima, plus 15 ssp. andreana provenances. In the phylogenetic tree, the wild and domesticated samples each formed well-defined clades (Figure 17). Domesticated entries conformed two sub-clusters; the first one comprised mostly Hubbard, Banana and Buttercup accessions, which is in concordance with [70]; meanwhile, the second encompassed Zapallito, Nugget and Moranga counterparts. Plomo entries were scattered along the two sub-clusters suggesting a less specific genetic makeup. Diversity 2021, 13, 354 15 of 19

ssp. Andrena; however, it clustered within the domesticated, has a medium size fruit and has a lack of seed dormancy, so it is clearly not ssp. andreana (Figure 14). Kates [40], using ~15,000 single nucleotide polymorphisms (SNPs), evaluated 32 im‐ proved and landraces entries of C. maxima, plus 15 ssp. andreana provenances. In the phy‐ logenetic tree, the wild and domesticated samples each formed well‐defined clades (Fig‐ ure 17). Domesticated entries conformed two sub‐clusters; the first one comprised mostly Diversity 2021, 13, 354 15 of 19 Hubbard, Banana and Buttercup accessions, which is in concordance with [70]; mean‐ while, the second encompassed Zapallito, Nugget and Moranga counterparts. Plomo en‐ tries were scattered along the two sub‐clusters suggesting a less specific genetic makeup. InIn thethe ssp.ssp. andreanaandreana clade,clade, aa sub-clusteringsub‐clustering waswas inin concordanceconcordance withwith provinces provinces (within (within Argentina)Argentina) and and also also to to fruit fruit characteristics; characteristics; entries entries from from Buenos Buenos Aires, Aires, Santa Santa Fe, Fe, C Córdobaórdoba andand SanSan LuisLuis showedshowed globularglobular greengreen fruits fruits with with light light yellow yellow stripes. stripes. ThoseThose fromfrom Entre Entre RRíosíos and and Santiago Santiago del del Estero,Estero, inin general,general, presentedpresented fromfrom ﬂattened,flattened, elliptical elliptical to to pearpear shape,shape, mottledmottled light light green green and and cream cream fruits fruits (Figure (Figure17). 17).

Figure 17. Phylogenetic tree of C. maxima adapted from [40]. In the domesticated clade, entries Figure 17. Phylogenetic tree of C. maxima adapted from [40]. In the domesticated clade, entries are areassigned assigned to cultivar to cultivar-groups‐groups according according to external to external fruits fruits characteristics, characteristics, otherwise otherwise indicated indicated as mis as‐ miscellaneous.cellaneous. In the In the wild wild ssp. ssp. andreanaandreana clade,clade, Argentinian Argentinian provinces provinces of provenances of provenances are are given, given, and and for forthose those included included in [59], in [59 the], the original original tripartite tripartite code code is also is also indicated. indicated.

TheThe jointjoint analysisanalysis ofof morphological morphological andand molecularmolecular datadata ofof the the 159 159 accessions accessions along along thethe Procrustes Procrustes approach approach [ 75[75]] is is presented presented in in Figure Figure 18 18.. The first axis that accounted for 34.5% of the variation clearly separates ssp. andreana entries from the rest of the cultivated forms, with the exception of 129unk (Ovo de Ganso). The second axis segregates the C. maxima domesticated entries where Zapallito, Zipinka and Nugget cultivar-groups were placed to the lower quadrant; Turban and Buttercup cultivar-groups have a more central placement; meanwhile, Hubbard, Plomo, Moranga and Banana cultivar-groups are positioned to the upper part, irradiating uppermost the Show cultivar-group (Figure 18). In C. pepo, clear separations in relation to cultivar-groups were observed for ssp. texana but not for ssp. pepo domesticates [31]. In C. pepo ssp. texana, the cultivar-group Scallop was centrally positioned in relation to the remaining cultivar-groups, and assigned a putative first domestication associated with the consumption of seeds and immature fruits [31]. In this sense, in C. maxima, the central core tendency of Turban and Buttercup cultivar-groups may reflect a first step in the domestication pathway, irradiating subsequently to more specialized selection for fruit flesh consumption, where fruit size and flesh quality were more desirable attributes, leading to Moranga, Hubbard, Banana, Plomo and Show cultivar- groups on one hand, and for immature fruit consumption related to long-day induction, precocity (bush habit) and adaptation to temperate climate, yielding Zapallito, Nugget and Zipinka cultivar-groups on the other hand. Diversity 2021, 13, 354 16 of 19 Diversity 2021, 13, 354 16 of 19

Figure 18. ProcrustesFigure 18. analysis Procrustes biplot analysis for morphological biplot for morphological and molecular and data molecular of 159 accessions data of 159 of accessionsC. maxima ofand C. out-group species. Codesmaxima are the and same out‐ asgroup in Figure species. 15. Codes are the same as in Figure 15.

The first axis thatThe accounted striking placement for 34.5% of of 129unk the variation (Ovo de clearly Ganso, separates MAX 24), ssp. more andreana related to wild ssp. entries from theandreana rest of thethan cultivated any of the forms, assessed with cultigens the exception so far, of can 129unk be reflecting (Ovo de eitherGanso). a relic of an old The second axisintermediate segregates domesticatedthe C. maxima form domesticated that scarcely entries survived where as Zapallito, weedy related Zipinka to anthropogenic and Nugget cultivardisturbance,‐groups or were a completely placed to specialized the lower small quadrant; size domesticate Turban and for Buttercup use as buoy in fishing cultivar‐groupsnets, have small a more containers, central rattles placement; or decorative meanwhile, purposes. Hubbard, This findingPlomo, strengthensMoranga the possible and Banana cultivardomestication‐groups placeare positioned of the species to the more upper easternward part, irradiating than previously uppermost believed the in concor- Show cultivar‐dancegroup with (Figure the 18). potential presence of the natural Peponapis pollinator and archeological In C. peporemains,, clear separations confirming in the relation intuition to cultivar of Whitaker‐groups and were Carter observed [76] of thefor ssp. Brazilian tex‐ origin of the ana but not forTurban ssp. pepo cultivar-group. domesticates [31]. In C. pepo ssp. texana, the cultivar‐group Scallop was centrally positioned in relation to the remaining cultivar‐groups, and assigned a pu‐ tative first domesticationSupplementary associated Materials: withThe the following consumption are available of seeds online and at https://www.mdpi.com/article/10 immature fruits .3390/d13080354/s1, Table S1: Details of accessions included in Lopez-Anido 2017 study. [31]. In this sense, in C. maxima, the central core tendency of Turban and Buttercup culti‐ var‐groups mayFunding: reflect Thisa first research step in was the fundeddomestication by Consejo pathway, Nacional irradiating de Investigaciones subsequently Científicas y Técnicas to more specialized(CONICET, selection Argentina) for fruit grant flesh number consumption, PUE0043. where fruit size and flesh quality were more desirableAcknowledgments: attributes, leadingGermplasm to Moranga, Resources Information Hubbard, NetworkBanana, (GRIN), Plomo USA, and forShow providing data and cultivar‐groupspictures on one of hand, mature and squash for accessions. immature IPK fruit Genebank, consumption Germany, related for passport to long data‐day on in some‐ accessions. duction, precocity (bush habit) and adaptation to temperate climate, yielding Zapallito, Conflicts of Interest: The author declares no conflict of interest. The funders had no role in the design Nugget and Zipinka cultivar‐groups on the other hand. of the study; in the collection, analyses or interpretation of data; in the writing of the manuscript or The strikingin the placement decision to of publish 129unk the (Ovo results. de Ganso, MAX 24), more related to wild ssp. andreana than any of the assessed cultigens so far, can be reflecting either a relic of an old References intermediate domesticated form that scarcely survived as weedy related to anthropogenic 1. Paris, H.S. Geneticdisturbance, Resources or a of completely Pumpkins and specialized Squash, Cucurbita small sizespp. domesticate In Genetics andfor Genomicsuse as buoy of Cucurbitaceae. in fishing Plant Genetics and Genomics:nets, Crops small and containers, Models; Grumet, rattles R., or Katzir, decorative N., Garcia-Mas, purposes. J., This Eds.; finding Springer: strengthens Cham, Switzerland, the possi 2016;‐ Volume 20, pp. 11–154. [bleCrossRef domestication] place of the species more easternward than previously believed in con‐ 2. Nee, M. Thecordance domestication with of theCucurbita potential(Cucurbitaceae). presence of theEcon. natural Bot. 1990 Peponapis, 44, 56–68. pollinator [CrossRef and] archeological 3. Whitaker, T.W.;remains, Cutler, confirming H.C. Cucurbits the andintuition cultures of inWhitaker the Americas. and CarterEcon. Bot. [76]1965 of the, 19 ,Brazilian 344–349. [originCrossRef of] the 4. Khoury, C.K.;Turban Carver, cultivar D.; Kates,‐group. H.R.; Achicanoy, H.A.; van Zonneveld, M.; Thomas, E.; Heinitz, C.; Jarret, R.; Labate, J.; Reitsma, K.; et al. Distributions, conservation status, and abiotic stress tolerance potential of wild cucurbits (Cucurbita L.). Plants People Planet. 2020 2 Supplementary, , 269–283. Materials: [CrossRef The] following are available online at www.mdpi.com/xxx/s1, Table S1: Cucurbita andreana Cucurbita maxima Rev. Arg. Agron. 1945 12 5. Millán, R. VariacionesDetails of accessions el zapallito included amargo in Lopez‐Anido 2017y el study. origen de . , , 86–93. Funding: This research was funded by Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET, Argentina) grant number PUE0043.

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