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(2313) Proposal to conserve the name Momordica lanata ( Citrullus lanatus ) (watermelon, Cucurbitaceae ), with a conserved type, against Citrullus battich</I

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identical to print version). TAXON 63 (4) • August 2014: 941–942 Renner & al. • (2313) Conserve Momordica lanata (2313) Proposal to conserve the name Momordica lanata (Citrullus lanatus) (watermelon, Cucurbitaceae), with a conserved type, against Citrullus battich. rej. prop. Typus non designatus. This proposal originated as a spinoff of new results of DNA sequencing in the genus Citrullus, which put the currently accepted name for the sweet watermelon in jeopardy. While it was being drafted, a second threat to that name surfaced, which is also being taken into account. The watermelon was first validly named by Linnaeus (Sp. Pl.: 1010. 1753) as Cucurbita citrullus L. That name has not as yet been typified effectively (see details in Jarvis, Order Out of Chaos: 465. 2007). According to Jarvis the original material comprises two ele-ments, an illustration (Bauhin & al., Hist. Pl. 2: fig. on p. 236. 1651) and a specimen in the Burser Herbarium. However, the illustration is not an original element. Linnaeus's protologue reference is to Citrul-lus folio colocynthidis secto, semine nigro, on page 235 of Bauhin & al.'s work, where that plant is indeed described but not figured. The figure on the following page (236) is of Gitruli [sic] genus aliud (a different kind), which is described in the text as Citruli genus majus (a larger kind), differing in a number of features of the fruit and seed. Therefore a single original element remains: the specimen of "Anguria Citrullus dicta" in herb. Burser VII: 101 (UPS), that we here formally designate as the (obligate) lectotype. Savage (C. Lin-naei Det. Hort. Sicc. J. Burseri: 57. 1937) confirms that the specimen was examined and identified by Linnaeus before 1753. It is indeed a flowering shoot of the watermelon, as we could verify on the digital images kindly put at our disposal by Mats Hjertson. The nomenclatural history of the watermelon is chequered. For about a century (mid-19th to mid-20th) the name Citrullus vulgaris was in general use for it. However, already in 1930 Bailey (in Gentes Herbarum 2: 180–186) pointed out that "the methods of nomenclature must be liberally interpreted in this case, unless one is willing to adopt the doublet Citrullus Citrullus, and even this double name may not be without doubt". Such doubts were appropriate both at the genus and species level. Ahead of the 1950 Stockholm Congress, Hara proposed conser-vation of Citrullus Forssk. 1775 against two earlier synonyms, Anguria Mill. 1754 and Colocynthis Ludw. 1757, all said to refer to the water-melon. A corresponding preliminary entry appears in the Stockholm Code (Lanjouw & al. in Regnum Veg. 3: 137. 1952). Fosberg (in Taxon 2: 99–101. 1953), having been assigned the proposal for examination, supported it in principle but concluded that Citrullus Forssk., having been proposed without generic description for a genus comprising three species, was not a validly published name. Fosberg therefore suggested that Citrullus be conserved from its publication by Schrader in 1836, with C. vulgaris Schrad. (≡ Cucurbita citrullus L.) as its listed type; and that Citrullus Neck. 1790 be added to the entry as a rejected earlier homonym. This was approved and is what appears in the Paris Code (Lanjouw & al. in Regnum Veg. 8: 273. 1956). Since then, the only changes affecting the entry have been elimination of the Necker homonym (as Necker's generic names had been ruled not to be validly published) and replacement of Colocynthis Ludw. with the earlier, supposedly isonymous Colocynthis Mill. 1754 (Rickett & Stafleu in Taxon 9: 121. 1960). Hara (in Taxon 2: 134–135. 1953) had, in vain, objected to Fosberg's change to his proposal. Of Hara's two arguments, one is spurious (Cucurbita anguria Duchesne 1786 is an illegitimate name and cannot threaten Cucumis vulgaris), but the other is valid. "Though Forskål described three species under Citrullus, the first was the only for which he introduced a binomial … Forskål's Citrullus with only one validly published binomial … may be regarded as a monotypic genus." The Code at that time did not clearly define what a "monotypic genus" is, so both Fosberg's and Hara's interpretations were possible. When the definition eventually was given, first in Art. 42 Note 1 of the Sydney Code (Greuter & al. in Regnum Veg. 111: 39. 1983) and then in Art. 42.2 of the Tokyo Code (Greuter & al. in Regnum Veg. 131: 52. 1994), it confirmed Hara's position. Citrullus Forssk. 1775 is a validly published name, heterotypic although synonymous with Citrullus Schrad., and therefore by implication (ICN Art. 14.10) rejected in favour of the latter as an earlier homonym. [Thanks to a last-minute fix, this is now made explicit in the Citrullus entry in App. III to the Melbourne Code, McNeill & al. in Regnum Veg. 157, in press.]
941Version of Record (identical to print version).
TAX ON
63 (4) • August 2014: 941–942
Renner & al.
• (2313) Conserve Momordica lanata
(2313) Proposal to conserve the name Momordica lanata (Citrullus lanatus)
(watermelon, Cucurbitaceae), with a conserved type, against Citrullus battich
Susanne S. Renner,1 Guillaume Chomicki1 & Werner Greuter2
1 Systematic Botany and Mycology, Department of Biology, University of Munich (LMU), 80638 München, Germany
2 Herbarium Mediterraneum, Orto Botanico, Via Lincoln 2/A, 90133 Palermo, Italy
Author for correspondence: Werner Greuter, w.greuter@bgbm.org
DOI
http://dx.doi.org/10.12705/634.29
(2313) Momordica lanata Thunb., Prodr. Pl. Cap.: 13. 1794 [Angiosp.:
Cucurbit.], nom. cons. prop.
Typus: Cultivated in St. Louis, Missouri, from seeds of com-
mercial origin, 4 July 2014, S.S. Renner 2816 (M; isotypi: B,
BM, K, L, LE, MO, P, PAL-Gr), typ. cons. prop.
(=) Citrullus battich Forssk., Fl. Aegypt.-Arab.: 167. Jun 1775, nom.
rej. prop.
Typus non designatus.
This proposal originated as a spinoff of new results of DNA
sequencing in the genus Citrullus, which put the currently accepted
name for the sweet watermelon in jeopardy. While it was being
drafted, a second threat to that name surfaced, which is also being
taken into account.
The watermelon was first validly named by Linnaeus (Sp. Pl.:
1010. 1753) as Cucurbita citrullus L. That name has not as yet been
typified effectively (see details in Jarvis, Order Out of Chaos: 465.
2007). According to Jarvis the original material comprises two ele-
ments, an illustration (Bauhin & al., Hist. Pl. 2: fig. on p. 236. 1651)
and a specimen in the Burser Herbarium. However, the illustration is
not an original eleme nt. Lin naeus’s pr otolog ue refere nce i s t o Citrul-
lus folio colocynthidis secto, semine nigro, on page 235 of Bauhin &
al.’s work, where that plant is indeed described but not figured. The
figure on the following page (236) is of Gitruli [sic] genus aliud (a
different kind), which is described in the text as Citruli genus majus
(a larger kind), differing in a number of features of the fruit and
seed. Therefore a single original element remains: the specimen of
Anguria Citrullus dicta” in herb. Burser VII: 101 (UPS), that we
here formally designate as the (obligate) lectotype. Savage (C. Lin-
naei Det. Hort. Sicc. J. Burseri: 57. 1937) confirms that the specimen
was examined and identified by Linnaeus before 1753. It is indeed a
flowering shoot of the watermelon, as we could verify on the digital
images kindly put at our disposal by Mats Hjertson.
The nomenclatural history of the water melon is chequered. For
about a centu ry (mid-19th to mid-20th) the name Citrullus vulgaris
was in general use for it. However, already in 1930 Bailey (in Gentes
Herbarum 2: 180–186) pointed out that “the methods of nomenclature
must be liberally interpreted in this case, unless one is willing to adopt
the doublet Citrullus Citrullus, and even this double name may not
be without doubt”. Such doubts were appropriate both at the genus
and species level.
Ahead of the 1950 Stockholm Congress, Hara proposed conser-
vation of Citrullus Forssk. 1775 against two earlier synonyms, Anguria
Mill. 1754 and Colocynthis Ludw. 1757, all said to refer to the water-
melon. A corresponding preliminary entry appears in the Stockholm
Code (L anjouw & al. in Reg num Veg. 3: 137. 1952) . Fosbe rg (i n Taxon
2: 99–101. 1953), having been assigned the proposal for examination,
supported it in principle but concluded that Citrullus Forssk., having
been proposed without generic description for a genus comprising
three species, was not a validly published name. Fosberg therefore
suggested that Citrullus be conser ved from its publication by Schrader
in 1836, with C. vulgaris Schrad. ( Cucurbita citrullus L.) as its
listed type; and that Citrullus Neck. 1790 be added to the entry as a
rejected earlier homonym. This was approved and is what appears in
the Paris Code (Lanjouw & al. in Regnum Veg. 8: 273. 1956). Since
then, the only changes affecting the entry have been elimination of
the Necker homonym (as Necker’s generic names had been r uled not
to be validly published) and replacement of Colocynthis Ludw. with
the earlier, supposedly isonymous Colocynthis Mill. 1754 (Rickett &
Staf leu in Taxon 9: 121. 1960).
Hara (in Taxon 2: 134–135. 1953) had, in vain, objected to
Fosberg’s change to his proposal. Of Hara’s two arguments, one is
spurious (Cucurbita anguria Duchesne 1786 is an illegitimate name
and cannot threaten Cucumis vulgaris), but the other is valid. “Though
Forskål described three species under Citrullus, the first was the only
for which he introduced a binomial … Forskål’s Citrullus with only
one validly published binomial … may be regarded as a monotypic
genus.” The Code at that time did not clearly define what a “monotypic
genus” is, so both Fosberg’s and Hara’s interpretations were possible.
When the definition eventually was given, first in A rt. 42 Note 1 of
the Sydney Code (Gr euter & al . in Regnu m Veg. 111: 39. 198 3) an d then
in Art. 42.2 of t he Tok yo C ode (Greuter & al. in Regnum Veg. 131: 52.
1994), it confirmed Hara’s position. Citrullus Forssk. 1775 is a validly
published name, heterotypic although synonymous with Citrullus
Schrad., and therefore by implication (ICN Art. 14.10) rejected in
favour of the latter as an earlier homonym. [Thanks to a last-minute
fix, this is now made explicit in the Citrullus entry in App. III to the
Melbourne Code, McNeill & al. in Regnum Veg. 157, in press.]
942 Version of Record (identical to print version).
TAX ON
63 (4) • August 2014: 941–942
Renner & al.
• (2313) Conserve Momordica lanata
At the species level, the correct name of the watermelon is to some
extent conditioned by taxonomic opinion. Bailey (l.c. 1930), Mansfeld
(in Kulturpf lanze, Beih. 2: 421–422. 1959) and many others in their
wake considered the watermelon to include wild southern African
plan ts i n ad ditio n to th e wide ly cu lti vated sweet wa ter melon . Wh ere as
Bailey, disregarding the laws of priority, included Momordica lanata
Thunb., as a variety, in the junior Citrullus vulgaris, Mansfeld drew
the (then inescapable) consequence and accepted Citrullus lanatus as
the correct name of the similarly circumscribed species. It turned out
that what Mansfeld in 1959 believed to be a new combination had in
fact been proposed much earlier, for the same reasons, in a Japanese
seed list: Citrullus lanatus (Thunb.) Matsum. & Nakai, Cat. Sem.
Spor. Hort. Bot. Univ. Imp. Tokyo 1915–1916: 30. 1916 (see Hara in
Taxon 18: 346–347. 1969).
Authors like Bailey, Mansfeld and some others were well aware
of the fact that the plant described by Thunberg was not the sweet
watermelon but a plant growing wild in S. Africa. Citrullus vulgaris
var. lanatus (Thunb.) L.H. Bailey (in Gentes Herbarum 2: 87. 1929)
was proposed to designate “the bitter or wild native watermelon of
South Africa”. Mansfeld (l.c. 1959), similarly, restricted the use of
C. lanatus var. lanatus to the southern African “wild watermelon”.
In Mansfeld, Verz. Landwirtsch. Gärtn. Kulturpf l., ed. 2: 932–934.
1986), C. lanatus is s ubdiv ide d into thre e subs pec ies w ith seve ral vari -
eties, with the sweet watermelon placed in subsp. vulgaris (Schrad.)
Fursa, as var. vulgaris (Schrad.) Fursa, and Thunberg’s S. African
plant in the autonymic subsp. lanatus, as var. lanatus.
However, the inevitable occurred. The sweet water melon came
to be generally known as Citrullus lanatus, irrespective of the fact
that its nomenclatural type represented a different plant. The USDA
Germplasm Resources Information Network, GR IN (http://www.ars
-g rin.gov/cgi -bin/n pgs/ht ml/t axon.pl?314923) a s wel l as Wier sem a &
León’s standard reference book, World Eco n omi c Plan ts (ed. 2: 179.
2013) use C. lanatus var. lanatus for the cultigen, sweet watermelon,
as opposed to var. citroides (L.H. Bailey) Mansf. applied to tsamma
melon, fodder melon and citr us melon. That state of affairs might
have been tolerable as long as all plants traditionally assigned to the
watermelon remained in one and the same species. But new results
of a combined morphological, geographic and molecular analysis
no longer permit to uphold such a concept. Nesom (in Phytoneuron
2011-13: 1–33. 2011) made a first step in that direction, recognising two
species: C. caffer Schrad. (which by implication includes Thunberg’s
type of C. lanatus) and “C. lanatus”, which excludes that type. Our
own results (Chomicki & Renner, submitted) go further along that
path. We analysed nuclear and plastid DNA sequences from all known
Citrullus species, most of them with multiple accessions, including
leaf fragments from the holotype of Momordica lanata (UPS-THUNB
22762) and from the lectotype of Citrullus caffer (GOET 007221;
Nesom, l.c.: 26, fig. 1). We found complete agreement between those
two type specimens (they share, in particular, a unique 30-base-pair
deletion in the plastid gene trnS-trnG). Furthermore, it has become
evident that the sweet watermelon, “C. lanatus”, is not immediately
related to S. Af rican plants but is sister to C. mucosospermus (Fursa)
Fursa from W. Tropical Africa; whereas the southern African popula-
tions form a separate lineage, in which Thunberg’s plant, the annual,
tendril-bearing citron melon (for which the name C. amarus Schrad.
1836 is available, which has priority over C. caffer Schrad. 1838) is
sister to a mor phologically quite distinct species, C. ecirrhosus Cogn.
1888, a perennial that lacks tendrils.
In our opinion, changing the name of as popular and economi-
cally impor tant a plant as the sweet watermelon must not be per-
mitted. It is by far the better solution to condone and legalise the
increasingly erroneous application of the name Citrullus lanatus
by conserving it with a type that, while discordant with Thunberg’s
original intent, sanctions the current all but universal practice. Since
2000 the name C. lanatus has been used in ca. 650 scientific papers
(Web of Science, accessed 25 May 2014) and countless publications
in the applied domain, all relating to the watermelon. The other con-
ceivable alternative, reverting to the once popular C. vulgaris, is not
a realistic option since that name is not available for use anyway
owing to Forsskål’s earlier name. The specimen here proposed as
conserved type of C. lanatus is one of those of which the DNA has
been extracted and sequenced.
Rejection of the present proposal would have two unwelcome
consequences: (1) The correct name of the watermelon would change
from Citrullus lanatus, not to the once familiar C. vulgaris, but to the
utterly unused C. battich Forssk. Forsskål’s name has been discussed
at l en gth by Bailey (l.c. 193 0: 182) w ho, even though no t ype mate rial
has been preserved, was satisfied of the identity of the plant described
with the watermelon, based on the distinctive pattern of seed testa
colour and the coincidence of the ver nacular name with its moder n
use. (2) Application of the name C. lanatus would have to swit ch fro m
sweet watermelon, its present well known meaning, to C. amarus, the
S. African wild citron melon, also cultivated as preser ving melon.
Even t hough C. lanatus has been widely and persistently used for a
taxon not including its type, ICN Art. 57 can no longer be applied if
this proposal should fail.
... According to recent research, including phylogenetic analyses and nomenclatural reviews (Chomicki et al., 2020;Renner et al., 2014) as well as a phenetic comparison within the genus (Achigan-Dako et al., 2015), Citrullus encompasses the following seven species: (a) ...
... Indeed, whereas some experts believe watermelon originated from southern Africa, based on the distribution of wild relatives in the Namibian desert (Bates & Robinson, 1995), others point to northern or northeastern Africa, especially the Nile river area in Sudan, as the likely center of origin based on archaeological data (Paris, 2015;Renner et al., 2019;Wasylikowa & Van Der Veen, 2004). According to these latter studies, very few archaeological records of watermelon are known from southern Africa, and all date to a relatively recent period between the 8th and 13th centuries A.D. Furthermore, a cultigen is known to have been cultivated in the Nile Valley when farming was not yet practiced in southwest Africa (Zohary & Hopf, 2000 deemed to be a subspecies or variety of C. lanatus (Achigan-Dako et al., 2015;Hammer & Gladis, 2014;Nesom, 2011;Renner et al., 2014). ...
... However, they are indeed two different species, as previous crosses between them (e.g., Charleston Gray x PI 560006) resulted in high levels of sterility (Gusmini et al., 2004). The very limited haplotype diversity among the two species suggests an old split with chlorotype fixation and ancient types of C. mucosospermus originating from West Africa (Renner et al., 2014). However, to the best of our knowledge, no wild populations have been con- has been rarely studied. ...
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The geographical origin of watermelon (Citrullus lanatus) remains debated. While a first hypothesis suggests the center of origin to be West Africa, where the endemic sister species C. mucosospermus thrives, a second hypothesis suggests northeastern Africa where the white‐fleshed Sudanese Kordophan melon is cultivated. In this study, we infer biogeographical and haplotype genealogy for C. lanatus, C. mucosospermus, C. amarus, and C. colocynthis using noncoding cpDNA sequences (trnT‐trnL and ndhF‐rpl32 regions) from a global collection of 135 accessions. In total, we identified 38 haplotypes in C. lanatus, C. mucosospermus, C. amarus, and C. colocynthis; of these, 21 were found in Africa and 17 appear endemic to the continent. The least diverse species was C. mucosospermus (5 haplotypes) and the most diverse was C. colocynthis (16 haplotypes). Some haplotypes of C. mucosospermus were nearly exclusive to West Africa, and C. lanatus and C. mucosospermus shared haplotypes that were distinct from those of both C. amarus and C. colocynthis. The results support previous findings that revealed C. mucosospermus to be the closest relative to C. lanatus (including subsp. cordophanus). West Africa, as a center of endemism of C. mucosospermus, is an area of interest in the search of the origin of C. lanatus. This calls for further historical and phylogeographical investigations and wider collection of samples in West and northeastern Africa. While the origin of watermelon is still debated, two endemic close relative are separately found in northeastern Africa and West Africa. Our paper presents the current chloroplast haplotypes distribution to infer the possible colonization route of watermelon using two cultivated and two wild relatives gathered from four continents.
... To date there seems to be a consensus regarding its complex taxonomy. According to recent research, including phylogenetic analyses and nomenclatural reviews (Renner et al., 2014;Chomicki et al., 2020) as well as a phenetic comparison within the genus (Achigan- Dako et al., 2015),Citrullus encompasses the following seven species: 1) the widely cultivated C. lanatus , a juicy fruit found in tropical and subtropical climates including var. cordophanus (Ter-Avan.) ...
... In contrast, archaeological records from West Africa are scanty, except for the presence of one endemic cultivated species (C. mucosospermus ) previously deemed to be a subspecies or variety of C. lanatus (Nesom, 2011;Hammer & Gladis, 2014;Renner et al., 2014;Achigan-Dako et al., 2015). ...
... The very limited haplotype diversity among the two species suggests an old split, with chlorotype fixation and ancient types of C . mucosospermus originating from Western Africa (Renner et al., 2014). However, to the best of our knowledge, no wild populations have been confirmed in West Africa. ...
... Watermelon (Citrullus vulgaris) has a place to the family Cucurbitaceae, a vine-like blooming originated from Africa [1,2]. It is for the most part developed for its fruits. ...
... Watermelon, a uncommon kind of berry with hard skin, was detailed to be developed tropical and subtropical region around the world [2]. Clearly, watermelon has sweet and juicy flesh and colour varying from profound red to pink, with numerous black seeds (Ogodo et al., 2015). ...
Article
Full-text available
PROXIMAE CHEMICAL COMPOSITION OF WATERMELON (Citrullus vulgaris)
... Watermelon (Citrullus vulgaris) has a place to the family Cucurbitaceae, a vine-like blooming originated from Africa [1,2]. It is for the most part developed for its fruits. ...
... Watermelon, a uncommon kind of berry with hard skin, was detailed to be developed tropical and subtropical region around the world [2]. Clearly, watermelon has sweet and juicy flesh and colour varying from profound red to pink, with numerous black seeds (Ogodo et al., 2015). ...
Article
Full-text available
The proximate chemical composition of watermelon (Citrullus vulgaris) was investigated. In addition, dicarboxylic fatty acids were determined using Gas chromatography/mass spectrometry. Results showed that the content of moisture, ash, crude protein, crude fibre, ash, lipids and carbohydrate contents ranged between 91.65-6.75%, 25.60-7.54%, 4.64-3.45%, 1.30-1.10%, 25.12-1.42% and 3.11-2.54%, in stems, leaves, green crust, kernels and seeds, respectively. Watermelon plant parts contained variable amounts of macro-minerals potassium (K), Calcium (Ca) and Magnesium (Mg) which ranged between 70.9-421.5 µg/ml, 2.46-343.1 µg/ml and 11.9-72.1 µg/ml in stems, leaves, green crust, kernels and seeds, respectively. Moreover, watermelon plant parts contained relatively small amounts of micro-minerals: copper, Cobalt, manganese, lead, Zinc and iron which ranged between-<0.1-9.69 µg/ml. The fatty acid analysis indicated that watermelon contain five saturated fatty acids; tetrdecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid and octadecanoic acid with different concentrations. The watermelon plant also contained four unsaturated fatty acids. The the most abundant fatty acids were Hexanoic and Eicosanoic acids (15%) while the lowest detected fatty acid was Octadecanoic acid (9%).
... Watermelon (Citrullus lanatus) belongs to the family Cucurbitaceae, a vine-like flowering plant of Africa origin (Maynard and Maynard, 2012;Renner et al., 2014). It is mostly cultivated for its fruits. ...
... citroides). Watermelon, a special kind of berry with hard rind, lacking internal division was reported to be grown in tropical and subtropical areas worldwide (Renner et al., 2014). Obviously, watermelon has sweet and juicy flesh and colour varying from deep red to pink, with many black seeds while seedless varieties are also common (Ogodo et al., 2015). ...
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This study evaluated the nutritional composition, physico-chemical and sensory properties of 'Robo' (a Nigerian traditional snack) produced from watermelon seeds in order to improve the utilization of watermelon seeds in producing value-added products, acceptable to the consumers. Watermelon seeds were dehulled, dried and used to prepared 'Robo' in the laboratory and control samples were prepared from melon seeds. The proximate analysis, amino acid profile, vitamin, mineral and heavy metal profile and consumer acceptance of the 'Robo' samples were determined using standard methods. The results showed that there were no significant differences (p≥0.05) in the proximate composition of the 'Robo' samples from watermelon and melon seeds. There were significant differences (p≤0.05) in amino acid, vitamin and mineral profile of 'Robo' samples from watermelon and melon seeds. The amino acid concentration in g/100 g crude protein of 'Robo' for lysine, arginine and leucine were 4.58±0.01, 1.82±0.00 and 4.92±0.01 respectively for 'Robo' produced from watermelon seeds while 4.91±0.01, 2.01±0.00 and 5.16±0.01 respectively were recorded for 'Robo' produced from melon seeds. The study showed that the 'Robo' samples contained high amounts of vitamin B-complex and minerals and low amounts of heavy metals. In conclusion, the 'Robo' samples from watermelon seeds and control samples had high sensory scores and were well acceptable to the consumers. With these research findings, watermelon seeds could be used for the production of 'Robo' as a promising raw material. This will create ready-made market for the underutilized watermelon seeds and as well as creating more income to watermelon farmers.
... In order to better understand the extent of taxonomic misnaming in databases of PGR accessions which are conserved ex situ and whether this issue could prevent their exploitation and conservation, we analysed and quantified the occurrence of this problem in seed accessions belonging to the watermelon genepool (Citrullus). We decided to focus on this genus as a case study, since it has a relatively small number of taxa (species and subspecies) and, after having been considered for long a critical taxonomic group, its systematics, taxonomy, and nomenclature have been revised and improved in recent years, with the aid of genetic investigation too (see Nesom 2011;Schaefer and Renner 2011;Chomicki and Renner 2014;Renner et al. 2014;Paris 2015). Moreover, Citrullus is of significant importance as a vegetable crop (Applequist 2016), with 3.5 million hectares of agricultural land used to cultivate watermelons in 2014 when annual production reached 111 million tons, which was 9.5% of global vegetable production, grown on 6% of the area used globally for the cultivation of vegetables (FAOSTAT 2017). ...
... In order to increase the possibilities of finding accessions, we also searched for the most widespread vernacular names (e.g., colocynth, tsamma, citron, egusi), with reference to geographic provenance and biological status (wild, landrace, modern cultivar) too. The resulting accession names were examined on nomenclatural grounds, by comparing them with the most updated taxonomic and nomenclatural treatments of Citrullus (see Nesom 2011;Chomicki and Renner 2014;Renner et al. 2014;Paris 2015); names were further checked in compliance with the rules of the International Code of Nomenclature for algae, fungi, and plants (ICN) (McNeill et al. 2012). A complete list of the accepted names and synonyms we came across in the consulted databases are provided in Online Resource 1. ...
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Full-text available
Ex situ conservation of plant germplasm, especially seed banking, is a favourable and widely used method for the conservation of plant genetic resources (PGR). The long-term conservation of these resources is fundamental for food security and plant breeding in order to stem the losses in agrobiodiversity and to meet the global challenges that agriculture is facing. The conservation and accessibility of PGR relies on their correct taxonomic labelling and on the building of a searchable database that links ex situ collections together. In the current study, we analysed the impact of taxonomic misnaming in the two major PGR databases (Genesys PGR, EURISCO), listing accessions conserved worldwide. The aim was to understand if taxonomic misnaming issues prevent PGR conservation. We chose as a case-study seed collections of accessions of the genus Citrullus (watermelon genepool), the taxonomy and nomenclature of which have been largely revised in recent times. We observed that taxonomic misnaming greatly limits PGR conservation with only 3% of the accessions listed in the databases correctly named; moreover, 28% were affected by taxonomic errors that prevent the establishment of the accessions’ taxonomic identity, with consequences on their conservation and exploitation. The existence of the problem was also confirmed by the experimental propagation of three misnamed accessions. We suggest herein a series of actions that, put in place, could solve the extant misnaming issues in the databases and prevent their reoccurrence, allowing the correct conservation and the usability by the stakeholders of all the accessions.
... Originally and more appropriately, citrullus was the southern European medieval Latin word for a small-fruited cucurbit, the cucumber, Cucumis sativus L. (Italian cetriolo) (Paris et al., 2011). Subsequent permutations of names for the genus and for the species of watermelons were recently discussed by Renner et al. (2014) in a much-needed proposal to conserve the name Citrullus lanatus. Three species of Citrullus -C. ...
... Genomic sequencing has revealed that the citron, egusi and dessert watermelons differ significantly in genome organization (Guo et al., 2013;Reddy et al., 2013;Chomicki and Renner, 2015), leading Chomicki and Renner (2015) to propose that each be considered a separate species, for a total of seven in the genus Citrullus (Table 1). Accordingly, the citron watermelon is C. amarus Schrad., the egusi watermelon is C. mucosospermus (Fursa) Fursa and the dessert watermelon retains the name C. lanatus (Renner et al., 2014). Caution must be exercised in identifying species of Citrullus based solely on individual phenotypic characteristics (Wehner, 2008). ...
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Watermelons, Citrullus species, are native to Africa and have been cultivated since ancient times. The fruit flesh of wild watermelons is watery, but typically hardtextured, pale-colored and bland or bitter. The familiar sweet dessert watermelons, C. lanatus, featuring non-bitter, tender, well-colored flesh, have a narrow genetic base, suggesting that they originated from a series of selection events in a single ancestral population. The objective of the present investigation was to determine where dessert watermelons originated. Archaeological remains of watermelons, mostly seeds, that date from 5,000 years ago have been found in northeastern Africa. An image of a large, striped oblong fruit on a tray has been found in an Egyptian tomb that dates to at least 4,000 years ago. The Greek word pepon, Latin pepo and Hebrew avattiah of the first centuries CE were used for the same large, thick-rinded, wet fruit which, evidently, was the watermelon. Wild and primitive watermelons have been observed repeatedly in Sudan and neighboring countries of northeastern Africa. The diverse evidence, combined, indicates that northeastern Africa is the center of origin of the dessert watermelon and that watermelons were domesticated for water and food there over 4,000 years ago. Next-generation ancient-DNA sequencing and genomic analysis offer opportunities to rigorously assess the relationships among ancient and living wild and primitive watermelons from northeastern Africa, modern sweet dessert watermelons and other Citrullus taxa.
... The cultivated citron, egusi, and dessert watermelons have been treated as subspecies of the single species Citrullus lanatus (Fursa, 1972). Although there are some cross-ability among them, genome organization data suggest to separate them into three different species (Renner et al., 2014;Paris, 2015): C. lanatus (Thunb.) Matsum. ...
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The sexual expression of watermelon plants is the result of the distribution and occurrence of male, female, bisexual and hermaphrodite flowers on the main and secondary stems. Plants can be monoecious (producing male and female flowers), andromonoecious (producing male and hermaphrodite flowers), or partially andromonoecious (producing male, female, bisexual, and hermaphrodite flowers) within the same plant. Sex determination of individual floral buds and the distribution of the different flower types on the plant, are both controlled by ethylene. A single missense mutation in the ethylene biosynthesis gene CitACS4, is able to promote the conversion of female into hermaphrodite flowers, and therefore of monoecy (genotype MM) into partial andromonoecy (genotype Mm) or andromonoecy (genotype mm). We phenotyped and genotyped, for the M/m locus, a panel of 207 C. lanatus accessions, including five inbreds and hybrids, and found several accessions that were repeatedly phenotyped as PA (partially andromonoecious) in several locations and different years, despite being MM. A cosegregation analysis between a SNV in CitACS4 and the PA phenotype, demonstrated that the occurrence of bisexual and hermaphrodite flowers in a PA line is not dependent on CitACS4, but conferred by an unlinked recessive gene which we called pa. Two different approaches were performed to map the pa gene in the genome of C. lanatus: bulk segregant analysis sequencing (BSA-seq) and genome wide association analysis studies (GWAS). The BSA-seq study was performed using two contrasting bulks, the monoecious M-bulk and the partially andromonoecious PA-bulk, each one generated by pooling DNA from 20 F2 plants. For GWAS, 122 accessions from USDA gene bank, already re-sequenced by genotyping by sequencing (GBS), were used. The combination of the two approaches indicates that pa maps onto a genomic region expanding across 32.24–36.44 Mb in chromosome 1 of watermelon. Fine mapping narrowed down the pa locus to a 867 Kb genomic region containing 101 genes. A number of candidate genes were selected, not only for their function in ethylene biosynthesis and signalling as well as their role in flower development and sex determination, but also by the impact of the SNPs and indels differentially detected in the two sequenced bulks.
... Matsum. & Nakai Watermelon Region of domestication controversial / Worldwide Fruit (seeds of certain cultivars are used as a snack in China) Loss of bitterness, acquisition of sweetness, lycopene accumulation, and fruit enlargement Ancient Upper Egypt / Sudan, earliest remains date to 5400 BP in Libya Van Zeist (1983), Wasylikowa & Van der Veen, (2004), Paris (2015 Citrullus mucoso spermus (Fursa) Fursa Egusi melon West Africa / West Africa Protein and lipid-rich seeds are eaten (they lack a hard seed coat) Larger seeds, richer in proteins and lipids (fruit pulp is not eaten) West Africa Fursa (1983), Prothro & al. (2012) The name Citrullus lanatus (based on Momordica lanata Thunb.) is conserved against C. battich Forssk., following acceptance of the proposal by Renner & al. (2014) at the XIX IBC in Shenzhen 2017. ...
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