The Citrus Route Revealed: From Southeast Asia into the Mediterranean

Botanical remains

The botanical remains discussed in this study include seeds (as well as some other fruit remains such as rinds), wood, charcoals, and fossil pollen grains. While the first two types of evidence are derived from archaeological sites, pollen is also extracted from sediment cores, aiming to reconstruct past vegetation and environmental conditions.

In this study, the validity of some of the botanical remains of citrus is evaluated for their reliability in terms of the following: 1) identification, 2) archaeological context, and 3) dating.

• 1) Identification—recent studies indicate that citrus seeds sometimes appear difficult to recognize because of their morphological variability, changes arising from preservation processes (Pagnoux et al., 2013), and their relatively poor state of preservation in the first place, mainly because citrus seeds are oily. The problem also lies in the similarity of the general morphology of citrus seeds to seeds of other taxa (e.g., Maloideae types—subfamily of the Rosaceae), especially when mineralized (Coubray et al., 2010; Pagnoux et al., 2013). Hence, more advanced methods are recommended when identifying citrus seeds, such as high-resolution microtomography technology, which enables 2D and 3D simulation to a scale of microns. By using this identification method, Coubray et al. (2010) reexamined the seeds from the sixth century BC site of Stipe dei Cavalli, Ischia, Italy, previously investigated by Coubray (1996). Their reexamination did not support the original attribution to citrus seeds and they should be identified as Sorbus domestica, a member of the Maloideae (Coubray et al., 2010). Pollen identification is more accurate than seed identification in the case of citrus; some recent studies even show that it is possible to distinguish Citrus to the species level, preferably by using a scanning electron microscope (Bui Thi and Girard, 2014; Russo-Ermolli et al., in press; Xianghong, 1982). In most cases, the identification of Citrus wood and charcoal remains is possible with high certainty only to the genus level (Schweingruber, 1990).

• 2) Archaeological context—great attention must be paid to the quality associations between botanical remains and the archaeological contexts from which the samples originate; the botanical remains should come from a secure context in terms of stratigraphy to prevent contamination or mixing with previous and later archaeological layers.

• 3) Dating—a critical issue in archaeology in general and in archaeobotany in particular; during historical periods, the dating of archaeological excavations relies mainly on typology of artifacts (such as pottery and coins) and ¹⁴C radiocarbon dating of organic material such as wood remains. More accurate ¹⁴C dating can be achieved by radiocarbon dating of short-lived macrobotanical remains such as seeds (to avoid the age of the wood sample itself), when they are clearly associated with the relevant archaeological context.

Art artifacts

Citrus fruits and trees appear in several forms of ancient artifacts, namely reliefs, wall paintings, mosaics, and coins. The main problems are related to the interpretation of the appearance of citrus on those objects in terms of the following: 1) the significance of their presence and 2) secure identification.

• 1) The appearance of citrus on ancient art and artifacts does not necessarily provide evidence of actual cultivation, but can suggest familiarity with citrus.

• 2) Citrus identification is particularly doubtful in the case of wall reliefs. Several suggestions were previously made connecting fruits appearing on ancient reliefs to citron. For example, the French archaeologist Loret (1891) claimed that at the Karnak Temple, Egypt, which was built in the time of Thutmosis III (15th century BC), citrons are evident in the relief. Another example comes from ninth century BC Assyrian reliefs in which cone-shaped objects held by human figures were identified by Bonavia (1894) as citrons. In my opinion, it is impossible to clearly define what was depicted in those reliefs. Other scholars reached the same conclusions when they failed to find a clear connection between the reliefs and the citron (e.g., Amar, 2009; Andrews, 1961). Since these two types of evidence are considered unreliable, they will not be discussed further.

Ancient texts

In this study, several sources of ancient texts have been used such as Jewish, Greco-Roman, and Arabic texts; these written sources were recently reviewed, respectively (Langgut, 2015; Pagnoux et al., 2013; Ramón-Laca, 2003). In the course of this track, some use of philology will be made when relevant.

Cultivation versus familiarity

The presence of pollen grains of insect-pollinated citrus is direct evidence of its actual growth in a given region (see below), unlike other archaeobotanical remains (seeds, rinds, charcoal and wood remains, and chemical analysis) that may reflect importation of fruit, small wooden objects, or even timber rather than the actual growing of the tree. In addition, since citrus plants are insect pollinated, they have low pollen dispersal efficiency. The occurrence of citrus pollen grains in a palynological spectrum is therefore direct evidence that it actually grew in the vicinity of the site in which it was found. As mentioned above, the occurrence of citrus in a wall painting may derive from familiarity with the fruit or even from foreign art experts hired to decorate a building and not necessarily on actual cultivation in a certain region.

Table 1.

The westward migration of citrus species.

Citron (C. medica)

The citron was the first citrus fruit to reach the Mediterranean, probably via Persia (Langgut, 2015; Langgut et al., 2013; Zohary et al., 2012). It originated in northeastern India or northern Southeast Asia, in the area from Assam, Myanmar, and Yunnan to the eastern Himalayan foothills, where it was probably also first domesticated (Fig. 1A; Fuller et al., 2011). This region is further west than the areas of origin of the other citrus species (Weisskopf and Fuller, 2013). Gur (1974) suggested that C. medica made its way from India to Afghanistan, Persia, Syria, Israel, and Egypt. The name may also shed some light on citron’s origin and diffusion route: In Hindi the citron is called torange, in Persian it is called toronge and later etronge, in Hebrew it is called etrog, in Aramaic etronga or etroga, and in Arabic turug or eturug. In Coptic the citron is ghitri, in Greek kitrea and kitrion, and in Latin the word citrus was used to name the tree and citreum or citrium for the fruit. The word medica in the Latin name (Citrus medica) may also suggest its Persian (Median) origin rather than its use for medical purposes. Tolkowsky (1966) mentions that during the 1950s and 1960s, C. medica trees that match Theophrastus’s description were grown in the Gilan province in Persia (Theophrastus, 1916), which was part of ancient Media [Theophrastus of Eresos (372–287 BC)—the great Greek botanist who wrote the Enquiry into Plants (Historia Plantarum) which contains elaborate and accurate description of Asian flora; a description of the citron tree appears in the fourth chapter of the book, which is dated to ≈310 BC].

Archaeobotanical evidence indicates that in the Nippur archaeological excavation, in the south of ancient Babylonia, citrus seeds dating to the Sumerian period (≈2000 BC) were discovered (cited by Bonavia, 1894: 68). Since the seeds found in the excavation were charred, they can only be identified as Citrus, and specific species cannot be determined. Tolkowsky (1966) pointed out that the period to which these seeds belong cannot be precisely dated. Furthermore, he emphasized that their presence in Nippur does not necessarily indicate that the tree from which they came was cultivated in Babylonia at that time. If the citron tree had grown there on a limited scale in ancient times, Tolkowsky (1966) believed it would have been a common tree during Alexander the Great’s conquest of the region in the late fourth century BC. The Greek botanists accompanying Alexander reported that the citron was grown only in Persia and Media (described in Theophrastus’ book). Tolkowsky (1966) therefore found the evidence from Nippur to be inconclusive; he claimed that if this seed assemblage was identified correctly, they were probably citron seeds brought to Nippur either as an offering to a divinity or as a gift to a king. Since the seeds were not dated directly, their age being assessed only by their archaeological context, which seems to be insecure, and since recent investigations show that the identification of citrus seeds requires advanced methods (Coubray et al., 2010; Pagnoux et al., 2013), which were not available at that time, it is therefore possible that the seeds were misidentified. This is also the case with the seeds which came from the archaeological site Hala Sultan Tekke (Cyprus), where seeds that resemble Citrus were discovered in a layer dated to the 12th century BC, but the exact species could not be identified (Hjelmqvist, 1979). Thus, these remains have not yet been directly dated to confirm their antiquity (e.g., by accelerator mass spectrometry radiocarbon dating; Zohary et al., 2012). Furthermore, those seeds originated from an insecure archaeological context because they were found in an unsealed stratum. Since the remains from Cyprus could not be found, the attempts to reexamine the seed assemblage were unfortunately not successful (D. Moster, personal communication).

Even if we accept the indefinite identification and inconclusive dating and context of the remains from Nippur and Cyprus, the presence of citrus seeds can only indicate that the fruit itself was present at the site, but this is not necessarily the proof that the tree was grown locally. Indeed, it appears that the citron was considered a valuable commodity since ancient times because of its healing qualities, symbolic use, and pleasant smell on the one hand and its rarity on the other (e.g., Zohary et al., 2012), possibly making the citron known to the people in the region by reputation throughout antiquity. Liran (2013) reached a similar conclusion, suggesting that the citron was a rare commodity that only the rich could afford. In addition, citron, unlike other citrus species is largely inedible and can be preserved for months because of its thick albedo. Therefore, it is likely that because of its relatively long shelf life, citron was used in antiquity as a long-distance elite trading product.

Recently published pollen findings from a Persian royal garden next to a lavish palace excavated at the Ramat Rahel site near Jerusalem, when the area was a Persian province (Lipschits et al., 2012) shed new light on the dating of the cultivation of C. medica in the Mediterranean (Langgut et al., 2013). While examining the plaster of one of the pools in the garden, dating to the fifth and fourth centuries BC, fossilized C. medica pollen grains were identified. They had been trapped in one of the plaster layers (various structures within the garden were plastered in several layers, probably because of ongoing maintenance). The unique palynological spectra extracted from this plaster layer included, in addition to C. medica, other palynological evidence of trees introduced from remote parts of the Persian empire, special trees highly valued by the ruling Persian authorities [e.g., the cedar of Lebanon (Cedrus libani)], together with native fruit trees and ornamentals. It should be noted that although citrus pollen is hardly ever airborne, it appears at high frequencies within Ramat Rahel’s palynological assemblages (up to 32%). During most of the period (second half of the fifth century BC and during the fourth century BC), the reconstructed climate conditions for the region (southern Levant) were relatively humid (Langgut and Lipschits, 2017), but the citron still probably required summer irrigation.

The next botanical evidence in chronological order derives from the sediment of the Punic port of Carthage (Tunis, North Africa) where a single pollen grain from the level contemporary with the fourth and early third centuries BC was extracted. According to van Zeist et al. (2001), this palynological evidence suggests that citrus was cultivated at this time in Carthage. In my opinion, due to the occurrence of only one pollen grain, the significance of this datum is very limited.

The occurrence of pollen, seed, and fruit remains of citron in several sites throughout the Mediterranean dated to the Roman period attests that by that time citron became much more known in the region. In the eastern Mediterranean, seeds and fruit remains from secure contexts were retrieved from several Roman settlements in Egyptian remote desert locations (Fig. 1A) dating to the first–fourth centuries AD [Quseir al-Qadim (van der Veen, 2011), Mons Porphyrites (van der Veen and Tabinor, 2007), Kellis, Dakhleh (Thanheiser et al., 2002), and Mons Claudianus (van der Veen, 1996, 2001)]; within the latter site not only C. medica seeds were found but also one near-complete fruit. Since the remains were desiccated, they were very well preserved. In the western Mediterranean, a relatively rich ensemble of both microbotanical and macrobotanical remains of C. medica is available, mainly from the Vesuvius area, which even predates the assemblage from Egypt. The earliest western Mediterranean archaeobotanical evidence is from Pompeii from a context dated to the third and second centuries BC, where several mineralized seeds of C. medica were found (Fiorentino and Marinò, 2008). A single mineralized seed was recovered from the second phase of the House of Hercules and Ebe’s Wedding, dating from the first half of the second century BC (Ciaraldi, 2007); Mariotti-Lippi (2000) extracted citrus pollen (most probably of C. medica and C. limon) from the garden of this house. Another mineralized seed was recovered from the House of the Vestals from a phase dated to the second half of the second century BC (Ciaraldi, 2007). Pollen identified as belonging to C. medica and C. limon was also recovered from Oplontis from a sediment sample dated to somewhere between the first century BC and the first century AD (Russo-Ermolli and Messager, in press). The Egyptian finds mentioned previously are more recent in comparison with the Italian finds. According to Pagnoux et al. (2013), one can therefore assume that the Romans played an important role in the spread of citrus into Egypt. A similar scenario was recently suggested in another eastern Mediterranean case, where a possible Roman influence on the vegetation of the Herodian garden at Caesarea was identified (Langgut et al., 2015).

Citrus pollen was also extracted from several sediment records taken from the Gulf of Naples (Cumae, Lake Averno, and Municipio excavation; Fig. 1B). In the relatively well-dated Municipio section, pollen grains identified as Citrus were recovered from several levels dated to the first century AD; Citrus pollen in previous or later levels was not present (Russo-Ermolli et al., 2014). Six pollen grains that were suggested to belong to C. medica or C. limon from a stratum dated to the Roman period were recognized in a Lake Averno sequence (Grüger and Thulin, 1998; Grüger et al., 2002). The case of the Cumae sediment record is more complicated because of chronological uncertainties (Bui Thi and Girard, 2014). Citrus pollen (not identified to the species level) starts to appear somewhere between two available ¹⁴C dates (but not right at the beginning), which covers a time interval from the mid-8th century BC to the second century AD. The palynological diagram presented by Bui Thi and Girard (2014, Fig. 4.13) is not consecutive, and no explanation is given by the authors. One explanation may be related to preservation issues as was the case with the lowermost and uppermost parts of the Municipio section, which were pollen barren (levels dated to the third and second centuries BC and the sixth century AD, respectively; Russo-Ermolli et al., 2014). Another explanation is mentioned by Grüger and Thulin (1998) in relation to their nearby record. The authors point out that hiatuses can be the result of regional earthquakes. Seismic events can also cause mixing of sediments, meaning that the pollen is not in situ. This possible disturbance may lead to palynological and chronological uncertainties within the Gulf of Naples’ sediments.

Because of the lack of a robust chronological framework in the Cumae record, the dating of the first appearance of citrus pollen should rely on a correlation with the better-dated nearby pollen records [Lake Averno (Grüger and Thulin, 1998; Grüger et al., 2002), and the Municipio section (Russo-Ermolli et al., 2014)]; it therefore should not be dated before the Roman period. This suggestion accords well with the other citrus botanical remains that their first appearance in the Vesuvius area is dated to the third and second centuries BC (mentioned previously). The palynological evidence from Cumae cannot therefore be considered as the earliest presence of Citrus within the Italian peninsula as was suggested by several scholars (e.g., Pagnoux et al., 2013). This is also the case with another early southern Italian find, a citrus-like fruit, which was discovered in a funerary offering dating back to the sixth century BC on the southern Italian island of Ischia, which was reidentified as Maloideae by using more advanced identification methods (Coubray et al., 2010).

Lemon (C. limon)

Until recently, the arrival of the lemon to the Mediterranean area was linked, like the arrival of many other citrus fruits, to the Muslim conquest (Table 1). However, some recent findings from Italy show that the lemon was already known to the Romans. The earliest reliable botanical evidence of C. limon (13 seeds and a skin fragment) was recovered from the Forum Romanum in Rome. According to Pagnoux et al. (2013), these botanical remains should be attributed to the late first century BC and the early first century AD. Palynological evidence from the later stage of the first century AD, from the Vesuvius area, indicates not only that C. medica trees were cultivated in gardens owned by the affluent but most probably also C. limon [House of Hercules and Ebe’s Wedding (Mariotti-Lippi, 2000); Villa Oplontis (Dimbleby and Grüger, 2002; Russo-Ermolli and Messager, in press); in the latter study, a possible dating range of first century BC–first century AD is suggested]. Within the latter villa, Jashemski et al. (2002) reported that carbonized wood from a tree air-layered in a broken amphora in the sculpture garden was identified as lemon. It may be a remnant of those trees planted in pots growing in protected areas along garden walls. Jashemski et al. (2002) also suggested that the depiction of yellow fruits dated to the first century AD on wall paintings from the House of the Fruit Orchard in Pompeii should be identified as lemon trees. In addition, based on the mosaic of about 100 AD in the Terme Museum in Rome, describing a basket of fruits, Jashemski et al. (2002) claimed that the Romans clearly distinguished the lemon and the citron as two different fruits; the lemon and the citron are each accurately portrayed showing their different characteristics and relative sizes.

All this archaeological evidence clearly indicates that the lemon arrived to the western Roman world as an elite product, though today it has great importance for European cuisine. The lack of early Roman texts mentioning the lemon as in the case for citron may suggest that its cultivation was very limited. There are no botanical or textual evidence from this period that lemon was growing in the Eastern Mediterranean. Only since the 10th century AD, were lemons mentioned in western parts of the Islamic world (Ramón-Laca, 2003). Later in the 12th century AD, a book named Treatise of the Dietetic Properties of the Lemon, in which all the qualities of this fruit are detailed, was written in Egypt by Ibn Jamiya, the physician to Sultan Saladin (Arias and Ramón-Laca, 2005). References from Medieval Cairo Genizah (Lev, 2015) and 13th century AD texts from Quseir (Fig. 1A; Guo, 2004), indicate that lemons were shipped from India to Egypt for medical purposes. Yet, according to van der Veen (2011), there is confusion in references between the lime and the lemon, and therefore, it is not certain which of the two fruit types was imported.

Sour (bitter) orange (C. aurantium)

The hybridization that resulted in the formation of the sour orange most probably took place in southern China or northern Indo-china (Weisskopf and Fuller, 2013). Based on the detailed textual survey conducted by Ramón-Laca (2003), it seems that the sour orange was introduced to Mesopotamia and the eastern Mediterranean and from there it migrated westward. Its introduction is dated to the 10th century AD based on various textual evidence; in his book Golden Lawns (dated to the 40s of the 10th century AD), al-Mas‘udi’s stated that the sour orange and a kind of “round fruit” (maybe lime?) were brought from India to Oman after the year 912 AD and then to Iraq, Syria, Palestine, and Egypt (Davidson, 2006; Ramón-Laca, 2003 and references therein). Al-Mas‘udi’s claims that in this migration, the sour orange lost much of its fragrance and color because it did not have the climate or the habitat specific to its place of origin (Calabrese, 1998). The sour orange had been previously cited by Ibn Wahshiyya (1993) in his version of the Nabatean Agriculture, compiled at the beginning of the 10th century. The sour orange, together with the lemon, was also mentioned by Ibn Djuldjul (1992) in his additions to Dioscorides’ Materia Medica, compiled in Cordoba between 982 and 994 AD.

No doubt the Arabs played a major role in the spread of the sour orange from the 10th century AD onward into Persia, Iraq, Syria, Palestine, and Egypt and apparently later into northern Africa, Sicily, Sardinia, and Spain (Webber, 1967). Indeed the name orange comes from a possible Dravic or Tamil root nurga (meaning fragrant) via Sanskirt nāranga (narunga) and Persian nārang (naranj) to Arabic nārandj; narantsion in late Medieval Greek and to the 14th century Spanish naranja (Davidson, 2006; Ramón-Laca, 2003). At the end of the 15th century, the Portuguese reported that they found many citrons and sour oranges on the east coast of Africa, but they found these trees only in cultivated gardens. It seems certain, therefore, that the Arabs, who had penetrated Egypt, Syria, Palestine, and North Africa in the first years of their conquests, had taken the sour orange with them (Webber, 1967). Botanical remains of citrus suggested to be of sour orange (yet, the identification of the species level cannot be made with confidence) were recovered from Islamic (mid-11th–13th century AD) Queir al-Qadim in the Egyptian desert (Fig. 1A; van der Veen, 2011).

Based on the occurrence of a fruit with a great resemblance to orange in several Roman mosaics and frescos, Tolkowsky (1938, 1966) suggested an earlier arrival of the orange to the Mediterranean. Yet, it is not clear whether the sour or sweet orange is depicted; Tolkowsky assumed that it was the sweet variety. In both a mosaic and a fresco from Pompeii dated to the first century AD, orange fruits were depicted; a mosaic from a Roman villa near Tusculum constructed in ≈100 AD shows a basket of fruits comprising an apple, a lemon, a citron, and two other fruits, suggested by Tolkowsky to be oranges. Yet, when Jashemski et al. (2002: 102) discussed this mosaic, they did not mention the possibility of oranges. Furthermore, within the entire book—The natural History of Pompeii (edited by Jashemski and Meyer, 2002), there is no evidence of any kind of the occurrence of oranges in the ancient gardens of Pompeii and the other Vesuvian sites. In the fourth century mosaic from the Mausoleum of Constantia, citrons, lemons, and oranges are depicted, all of them still attached to freshly cut branches carrying green leaves.

In my opinion, there are two possibilities regarding this artistic evidence: 1) the Roman artists were familiar to some extent with the exotic orange fruit, but the tree was not necessarily grown in the western Mediterranean; the artists may have seen the orange during their travels abroad; it is also possible that they were foreign art experts. 2) This artistic evidence represents an early arrival of orange, dated already to the first century AD, especially since some of the depicted oranges have remarkably faithful representation. Its westward migration from eastern Asia into the Roman world seems to reflect its exotic qualities and it therefore migrated as an elite product destined to luxurious Roman gardens. If at that stage it was grown only in the Vesuvius area, it may have vanished following the eruption. It could also have disappeared from Italy several times as a result of destructive freezes, disease, and even political disturbance. It is also known that the acclimatization process of foreign plants sometime involves several introductions, especially in the case of citrus that require careful cultivation. During the Roman period, the trees may have been reintroduced from eastern Asia or from Persia in planting pots just as Pliny mentioned for citron. Its later arrival, which is linked to the Islamic conquest, dated to the 10th century AD, is as a cash crop, as part of the phenomenon of citriculture.

Lime (C. aurantifolia)

This natural hybrid of citron and papeda (C. micrantha) originated in the tropics, probably in Malaysia or the East Indian archipelago (Scora, 1975). The first textual evidence of lime cultivation outside Southeast Asia is in a text written by Abū ’l-Jayr and Abū l-Khayr al-Ishbīlī (1991) from Seville sometime between the 11th and 12th centuries (Ramón-Laca, 2003). The first actual botanical remains also date to the same period; lime fruit remains were recovered from the Islamic site Queir al-Qadim in the eastern Egyptian desert (Fig. 1A) from contexts dated to the 11–13th century AD. The relatively rich assemblage was composed of 38 seeds and 48 rind fragments (van der Veen, 2011). According to van der Veen (2011), these remains represent the only archaeobotanical record for lime in Egypt and possibly the only lime remains which have been found so far in the Mediterranean Basin. Yet, van der Veen (2011) claims that lemon seeds from Medieval Syrian sites (11–14th century AD) show great resemblance to the type of Queir al-Qadim’s lime seeds and in her opinion were previously misidentified (as lemon instead of lime). Whereas van der Veen claims in high certainty that limes were brought to the eastern desert from other locations in Egypt and were also shipped from India as pickles, Thanheiser et al. (2002) pointed out that citrus trees could have been cultivated in the western Egyptian desert as a garden plant in the oasis. Since no fossil lime pollen grains have ever been found in Egypt, it is difficult to accept or reject either opinion (cultivation vs. shipping). There is of course also a possibility that the two approaches are correct, especially since the remains were found in two different eras (Roman and Islamic periods) and the citrus types (citron vs. lime) are different.

Pummelo (C. maxima)

This true Citrus species originated under tropical conditions, probably in mainland Southeast Asia (Miller and Gross, 2011; Weisskopf and Fuller, 2013) and the Malay Archipelago (Scora 1975). Its name can be traced back to the Malay word pumpulmas, which may itself have been borrowed from another language. The climate in most of Europe is much too cool for the pummelo, except in warmer areas such as southern Spain, where it was introduced by the Arabs. The first mention of pummelo cultivation in Spain is that of Abū ’l-Jayr and Abū l-Khayr al-Ishbīlī (1991) from Seville, dating between the 11th and the 12th centuries AD (Ramón-Laca, 2003). At the same time, al-Tignari from Granada also mentioned the pummelo in his writings and so did a little later by Ibn al-‘Awwam (1802). In Jacques de Vitry’s writings from the early 13th century, it is mentioned that a fruit named poma Adam (Adam’s apple, possibly a form of pummelo) occurred in Palestine. This region is also characterized by a relatively warmer climate and is therefore suitable for pummelo cultivation.

Sweet orange (C. sinensis)

The first mention of the sweet orange in Europe is sometimes said to be in the archives of the Italian city of Savona, in 1471. However, Platina (1475, but he prepared his manuscript in the preceding decade) provides a better starting point because he distinguished between sweet and sour orange. Gallesio (1811) concluded from his historical study that the sweet orange probably reached Europe first through the commercial trade route established and maintained by the Genoese. Later, during the 16th century AD, the Portuguese and particularly the travels of circumnavigation to the east carried out by Vasco de Gama contributed much to the spread and popularization of orange growing, by introducing a superior variety. Indeed, in 1498, Vasco de Gama saw in Mombaça “very good oranges, much better than those from Portugal” (Herculano, 1861: 36). On the other hand, some images (it is not clear whether they were sweet or sour) are questionably proposed to represent oranges in early Roman art (mentioned previously in relation to the sour orange).

Mandarin (C. reticulata)

Mandarin (C. reticulata), a true Citrus species, originated in China and northeast India (Fig. 1A; Scora, 1975; Spiegel-Roy and Goldschmidt, 1996) and was cultivated in its area of origin from a very early date, but it was the last major citrus fruit to travel to the west. The first specimen of a mandarin cultivar was brought from China to England in 1805 and then to Italy, where it became well established before 1850. From Italy, its cultivation spread quickly to other Mediterranean countries (Davidson, 2006). Other mandarin cultivars reached the Mediterranean Basin afterward.