Hindawi Publishing Corporation Advances in Agriculture Volume 2014, Article ID 541097, 8 pages http://dx.doi.org/10.1155/2014/541097 Review Article Origin, Domestication, and Dispersing of Pear (Pyrus spp.) G. J. Silva, Tatiane Medeiros Souza, Rosa Lía Barbieri, and Antonio Costa de Oliveira Plant Genomics and Breeding Center, Federal University of Pelotas, 96001-970 Pelotas, RS, Brazil Correspondence should be addressed to Antonio Costa de Oliveira; acostol@terra.com.br Received 11 March 2014; Accepted 29 April 2014; Published 9 June 2014 Academic Editor: Innocenzo Muzzalupo Copyright © 2014 G. J. Silva et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. he pear (Pyrus communis L.) is a typical fruit of temperate regions, having its origin and domestication at two diferent points, China and Asia Minor until the Middle East. It is the ith most widely produced fruit in the world, being produced mainly in China, Europe, and the United States. Pear belongs to rosaceous family, being a close “cousin” of the apple, but with some particularities that make this fruit special with a delicate lavor. hus, it deserves a special attention and a meticulous review of all the history involved, and the recent research devoted to it, because of the economic and cultural importance of this fruit in a range of countries and cultures. herefore, the purpose of this literature review is to approach the history of the origin, domestication, and dispersal of pears, as well as reporting their botany, their current scenario in the world, and their breeding and conservation. 1. Introduction Pear, a typical fruit of temperate climates, with delicate pleasant taste and smooth, has a wide acceptance throughout the world. By its shape, it inspires designers and architects. he fruit pleases generations; already in 1661, Jean-Baptiste de La Quintinie, lawyer and botanist, responsible for the gardens of the Versailles palace, passionate about the cultivation of pears, wrote in reports: “It must be confessed that, among all fruits in this place, nature does not show anything so beautiful nor so noble as this pear. It is pear that makes the greatest honor on the tables. . .” he pear is mainly consumed in natura, pies, cakes, accompanying strong cheese or carpaccio, risotto, jams, and ice creams and is a great fruit to be consumed in diets because of its low caloric value. It has high nutritional value with reasonable amounts of vitamins A, B1, B2, B3, and C and minerals like sodium, potassium, phosphorus, calcium, magnesium, and iron. It has a lot of iber, giving excellent results in the treatment of constipation and intestine inlammation. Many recommend pears to cure anomalies such as cystitis and kidney stones [1]. Belonging to the genus Pyrus, which originated in the Tertiary period, in Western China, the pear had its dispersion from northern Italy, Switzerland, former Yugoslavia, Germany, Greece, Moldova, and Ukraine to the East, in countries such as Iran, Uzbekistan, China, Japan, Korea, and Bhutan. Commercially, it is divided into two major groups: European and Asian pears. he irst, with elongated and full-bodied texture, and the second, with sandy texture and rounded body, make this fruit the ninth in world production, being mainly a commodity in China [2–4]. 2. Taxonomy, Origin, and Speciation he name pear is derived from Latin, pera or pira, with some variants like in French as poire, in German as peer, and in Greece as acras as wild type and apios as cultivated pear. It belongs to Equisetopsida C. Agardh class of vascular plants, Magnoliidae Novák ex Takht subclass, characterized by plants that have ribbed leaves and lowers. Belonging to the Rosales Bercht. & J.Presl order, and Rosaceae Juss family, with hermaphrodite lowers, polypetalae and perigynics stamens, the pear, of Pyrus L., gender is a fruit of big importance for the agriculture of latitude moderate countries, being cultivated on a large scale in China, Western Europe, and the United States [5–7]. he Maloideae subfamily, where the Pyrus gender belongs, has a basic chromosome number as � = 17, which is fair if compared with other species of Rosaceae, where � = 7 or � = 9. Of the three hypotheses that emerged 2 from the 1920s to explain the event, the most accepted theory [8] suggests an allotetraploid or allopolyploid from the cross between two primitive forms of Rosaceae family, Prunoideae with � = 8 and Spiraeoideae with � = 9. his theory was based on the observation of a predominance of univalent (unpaired chromosomes) and not from multivalent chromosomes during meiosis. Subsequently, isozyme studies supported this theory [9]. Most cultivated pears are diploid (2� = 34), but there are a few polyploid cultivars of P. communis and Pyrus × bretschneideri. According to some authors [9], the speciation of Pyrus occurred without a change in chromosome number. It is believed that gender Pyrus originated during the Tertiary period (65 to 55 million years ago) in the mountainous regions of western China where a very large number of species of the gender Pomoideae and Prunoideae are concentrated. Taking into consideration the areas of distribution of the various genres of Pomoideae, it is likely that the common ancestor of these was widely distributed in that territory during the Cretaceous or Paleocene and prior to the Tertiary. Evidence suggests that pear dispersion and speciation followed the mountain ranges to both the east and the west [10, 11]. In this period, only few traces of leaves in some localities from eastern Europe and the Caucasus were found, as the village of Parschlug, Austria, and the Kakhetia mountains, where Pyrus theobroma fossils were found. Whereas in eastern Georgia, Horizon Akchagyl, Azerbaijan, and Turkey, Pyrus communis L. fossil leaves were also found. In postglacial records, traces of fruits were found in lacustrine deposits in Switzerland and Italy [12]. It is believed that the process of domestication followed what is currently seen in the Caucasus, where one can ind many types of pear trees that grow abundantly [13]. here are two domestication centers and primary origin of the genus Pyrus: the irst is located in China, the second located in Asia Minor to the Middle East, in the Caucasus mountains, and a third secondary center located in Central Asia [14, 15]. he number of cataloged species varies greatly according to the interpretation of each author, 20 to 75 species [16]. here are 23 wild species cataloged, all native to Europe, temperate Asia, and northern mountainous regions of Africa [7, 17, 18]. Pears are classiied into three groups according to the number of carpels and fruit size: small fruits that have two carpels known as Asian pears, large fruits with ive carpels, and fruits with three to four carpels that are hybrids of fruits mentioned above. Asian pears have a crisp texture, while the European pear has a buttery and juicy texture, with characteristic lavor and aroma. Pears are propagated by grating, where the grat is adapted against stresses such as soil alkalinity, drought, cold. Species diversity is concentrated in western Eurasia to eastern Asia and especially in China (Table 1), but several species are mentioned by many authors, without a consensus, which hampers an organization, as many are hybrids between species, and in some cases, diferent regions use diferent names for the same cultivars [10, 19, 20]. In these two regions, two distinct groups of species, eastern and western, are formed Advances in Agriculture (Table 2). Studies indicate that there is a large genetic distance between these two groups [21]. he irst is focusing on most cultivated pears, found in Europe, North Africa, Asia Minor, Iran, part of Soviet Central Asia, and Afghanistan. he second group includes species that are concentrated in East Asia, the Tien-Shan and Hindu Kush mountains, and Japan. In the latter, there is a very large group of cultivars in China and Japan [11, 22]. Currently there are several works that aim to estimate the genetic distance among the diferent cultivars, concentrated in gene banks and breeding programs. Researchers at the University of Lleida (UDL-ETSIA) could estimate the genetic distance of 141 Spanish accessions of P. communis (past and current) through eight SSR markers. hirteen well-known Spanish cultivars that represent their diversity were also used, but all thirteen were grouped into a single cluster, showing the narrow genetic base of cultivars P. communis in Spain, mainly caused by market demands [23]. Another study was conducted by a group of Chinese researchers, in which, through six SSR markers, it was possible to verify the genetic distance of 98 species of Pyrus, including 51 Pyrifolia, Japanese and Chinese Pyrus, 11 P. ussuriensis, 24 Chinese white pears, six wild types, two Korean species, two P. communis cultivars, and 2 unidentiied types. he results showed the grouping of these cultivars in 10 groups, with 4 groups composed of white and sandy pears of Chinese and Japanese origin. he results showed that Japanese cultivars have as parents, Chinese sandy pear. Western cultivars formed separated and distant groups from the eastern pears [24]. Many studies have been conducted in the context to identify genetic variations and clustering of populations of cultivated pear in China, since the fruit is a commodity of great importance to this country, as a study of 233 landraces of P. pyrifolia, the “sandy pear,” was able to determine the level of genetic diversity and relatedness of companies by 14 SSR markers [25]. In 2013, the pear genome sequencing was completed by combining the illumina sequencing technology and a BAC by BAC (bacterial artiicial chromosome) strategy in an Asian pear named “Suli” [26]. his strategy minimized the limitation of the sequencing of a heterozygous genome. he results showed a frequency of 1.02% of SNPs and 53.1% of repeated sequences in the pear genome. It was veriied that the genomic portion of pear and apple is very similar, and the major diferences between them are the repeated sequences that are actively transposing. he pear genome sequencing project concluded that the average density of genes is one per 12 kb in at least 42,812 gene loci, a similar number comparing to other plants, and that the pear and apple genome are almost equal in gene numbers. he project also showed that the lignin content found in pear is similar to that of poplar, indicating that this lignin content is involved in the stone cell formation [26]. From the genomic approaches used in this project, a better understanding of this fruit crop has been achieved, which will relect on future improvements. Advances in Agriculture 3 Table 1: Pyrus species and hybrids from Asia. Species Pyrus alnifolia (S. and Z.) Franch. and Sav. Pyrus armeniacifolia T. T. Yu P. aucuparia var. randaiensis Hayata Pyrus baccata L. Pyrus baccata var. aurantiaca Regel Pyrus baccata var. himalaica Maxim. Pyrus baccata var. mandshurica Maxim. Pyrus betulifolia Bunge Pyrus × bretschneideri Rehder Pyrus calleryana Decne. Pyrus calleryana var. dimorphophylla (Makino) Koidz. Pyrus calleryana var. fauriei (C. K. Schneid.) Rehder Pyrus calleryana var. koehnei (C. K. Schneid.) T. T. Yu Pyrus cathayensis Hemsl. Pyrus delavayi Franch. Pyrus discolor Maxim. Pyrus doumeri Bois Pyrus folgner (C. K. Schneid.) Bean Pyrus foliolosa Wall. Pyrus glabra Boiss. Pyrus gracilis Siebold and Zucc. Pyrus harrowiana Balf. f. and W. W. Sm. Pyrus heterophylla Regel and Schmalh. Pyrus hondoensis Nakai and Kikuchi Pyrus × hopeiensis T. T. Yu Pyrus hupehensis Pamp. Pyrus indica Wall. Pyrus japonica hunb. Pyrus keissleri (C. K. Schneid.) H. Lev. Pyrus kansuensis Batalin Pyrus lanata D. Don Pyrus matsumurana Makino Pyrus nussia Buch.-Ham. ex D. Don Pyrus × phaeocarpa Rehder Pyrus pohuashanensis Hance Pyrus prattii Hemsl. Pyrus prunifolia Willd. Pyrus pseudopashia T. T. Yu Pyrus pyrifolia var. pyrifolia Pyrus ringo Wenz. Pyrus ringo var. kaido Wenz Pyrus scabrifolia Franch. Pyrus scalaris (Koehne) Bean Pyrus × serrulata Rehder Pyrus sieboldii Regel Pyrus sikkimensis Hook. f. Pyrus sinensis var. maximowicziana H. Lev. Pyrus × sinkiangensis T. T. Yu Pyrus spectabilis Aiton Pyrus taiwanensis Iketani and H. Ohashi Site of origin Russian Far East, China, Japan, Korea, Taiwan China Taiwan Russia, Mongolia, China, Korea Russia, Mongolia, China, Korea China, Bhutan, India, Nepal Russia, China, Japan, Korea China, Laos China China, Korea, Taiwan, Vietnam Japan Korea China China China China China, Taiwan, Laos, Vietnam China Burma, Bhutan, India, Nepal, China Iran Japan China, India, Nepal, Burma Kyrgyzstan, Tajikistan, China Japan China China, Taiwan South Asia and Far East Asia Japan China, Myanmar China Afghanistan, India, Nepal, Pakistan Japan Far East, South Asia China Russia, China, Korea China China China China, Laos, Vietnam China, Korea China China China China China, Japan China, Bhutan, India Korea China China Taiwan Crop ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ USA, Canada ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ 4 Advances in Agriculture Table 1: Continued. Species Pyrus ussuriensis Maxim. Pyrus × uyematsuana Makino Pyrus vestita Wall. ex G. Don Pyrus vilmorinii (C. K. Schneid.) Asch. and Graebn. Pyrus xerophila T. T. Yu Pyrus yunnanensis Franch. Pyrus zahlbruckneri (C. K. Schneid.) Cardot Pyrus tschonoskii Maxim. Pyrus cydonia L. Pyrus germanica (L.) Hook. f. Pyrus korshinskyi Litv. Pyrus kumaoni Decne. Pyrus salicifolia Pall. Pyrus trilobata (Poir.) DC. Pyrus turkestanica Franch. ∗ he same origin. Source: USDA (2012) [5]. 3. Domestication and Breeding Domestication has as a consequence the change in gene frequencies regarding to the original populations. A fully domesticated species is dependent upon man for its survival; in other words, it cannot reproduce in nature itself. he domestication of fruits began only around 6,000 years ago, through vegetative propagation, due to high rate of heterozygosity in them. As a consequence, self-fertility in pear and peach trees, hermaphroditism in grape, parthenocarpy, seedless fruits on banana, and absence of spines in some fruits [27] emerged. During this period, ancient Mediterranean fruits such as grape, olive, ig, and pomegranate have been domesticated. Even citrus, banana, apple, pear, quince, medlar, almond, apricot, cherry, peach, and plum were domesticated in Central and East Asia. Some fruits such as kiwi, blueberry, and pecan were domesticated only in the 19th and 20th centuries. he earliest mention of growing pears in Europe was made by Homer in ancient Greece, a little less than three thousand years ago, who wrote that “Pears are a git of God” [2]. It was then that breeding started and also the history of the pear as a cultivated plant. heophrastus (371– 287 BC), another Greek, also made important reports on pear. he same distinguished the wild forms from cultivated ones and suggested that bred genotypes received a special name and other important observations on breeding in general [28]. A large contribution to pear cultivation was made by the Romans. Portius-Cato (235–150 BC) described the methods of propagation, grating, and caring for fruit and also described six cultivars of pear. Another great writer of ancient Rome, Terentius Varro, dedicated some of his work to agriculture (116–27 BC), describing grating methods and storage. Among the Roman historians, the most important of all was Pliny the Elder (23–79 AD), who described in detail almost all varieties of the season, in a manuscript with more than sixty editions. In summary, the ancient Romans Site of origin Russia, China, Japan, Korea, Brazil Japan, Korea China, Bhutan, India, Nepal, Myanmar China China China, Myanmar China Japan Iran, Armenia, Azerbaijan, Russia, Turkmenistan Middle East and Northern Asia Afghanistan, Tajikistan, Uzbekistan Middle East, Far East and South Asia Iran, Armenia, Turkey, Arzebaijão Israel, Lebanon, Turkey, Bulgaria, Greece Kyrgyzstan, Tajikistan, Turkmenistan, Afghanistan Crop Brazil ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ reported more than 40 cultivars existing in the 1st century BC and described methods of cultivation similar to the practiced currently [2, 28]. Little is known about introducing pear in France, but in the mid-800, the cultivation has developed very well on site, making the country in the sixteen and seventeen centuries the world’s largest producer of the fruit. During the eighteenth century, Belgium developed numerous cultivars, including some that are important even today, as the varieties “Beurre Bosc,” “Beurre d’Anjou,” “Flemish Beauty,” and “Winter Nelis” [2]. he pear improvement happened in Europe from two species: Pyrus communis and P. nivalis. he irst, European Common pear, is completely barren and has in its gene pool an inluence of other species such as P. eleagrifolia, P. spinosa, P. nivalis, and P. syriaca [29]. he second, used to make wine, has been of great importance in Britain and France for over 400 years. Most cultivars released in Europe were developed via open pollination and fruits were selected according to their sotness and buttery aspect. In Asia, the cultivation began over 2500 years ago, with the main species Pyrus pyrifolia, Pyrus serotina, and Pyrus ussuriensis. he result was reported in written Chinese (Shi Jing) and other books for at least 1500 years [30]. In Japan, pear seeds dating from the years 200–300 were found. During the Edo period in Japan (1603–1868) over 150 cultivars were documented; this time the pears were planted in the corners, like a talisman to avoid the “evil eye.” One of the main characteristics of Asian pears is the crispy, sweet, and juicy acid pulp. he pulp is characterized by having “stone cells” which are sclerenchyma cells that difer from iber because they are very elongated. hey also ofer a sandy texture to the fruit [2]. he sizes vary from rounded as apples, these being the most cultivated, until pears to the top and bottom elongated bulbous pears, similar to the European pears. he fruits are very sensitive to physical damage, both at harvest and in the classiication as storage and marketing. Advances in Agriculture 5 Table 2: Pyrus species and hybrids originating in Europe and Southern Africa. Species Geographic distribution-site of origin Pyrus aria (L.) Ehrh. Canary Islands, North Africa, All of Europe North Africa, Middle East, Central Europe Oriental and Southern and Turkmenistan All Europe Azerbaijan, Turkmenistan, Iran Pyrus aria (L.) Ehrh. var. cretica Lindl. Pyrus aucuparia var. dulcis (K.) A. and G. Pyrus boissieriana Buhse Pyrus korshinskyi Litv. subsp. bucharica (Litv.) B. K. Pyrus bulgarica Kuth. and Sachokia (Pyrus × nivalis Jacq.) Pyrus caucasica Fed. Pyrus chamaemespilus (L.) Ehrh. ∗ UK, Portugal, Spain, France Algeria, Morocco Pyrus cuneifolia Guss. Pyrus decipiens Bechst. Pyrus domestica (L.) Sm. Pyrus elaeagrifolia Pall. Pyrus elaeagrifolia subsp. kotschyana Pyrus germanica (L.) Hook. f. Pyrus gharbiana Trab. Pyrus intermedia Ehrh. Pyrus malus subsp. paradisiaca (L.) Schubl. and G. Martens Pyrus minima Ley Pyrus nebrodensis Guss. Pyrus pinnatifida Ehrh. Pyrus praemorsa Guss Pyrus sachokiana Kuth. Pyrus spinosa Forssk. Pyrus sudetica Tausch Pyrus syriaca Boiss. Pyrus torminalis (L.) Ehrh. Pyrus trilobata (Poir.) DC. ∗ he same origin. Source: USDA (2012) [5]. North America ∗ Western Europe, Central Eastern and Southern Eastern Europe and Central Greece Western Europe, Central Eastern and Southern P. communis var. cordata (Desv.) H.f. P. communis subsp gharbiana (T.) Maire P. communis subsp. marmorensis (Trab.) Maire Pyrus crataegifolia Savi ∗ ∗ All Europe Pyrus × complexa Rubtzov Pyrus cossonii Rehder ∗ Former Soviet Union Pyrus communis L. P. communis subsp. pyraster (L.) Ehrh. Crop ∗ ∗ Eastern Europe Central, South and West, and South America ∗ ∗ Morocco ∗ Western Europe, Central Eastern, and Southern Former Soviet Union Algeria Turkey, Albania, Serbia, Greece, Italy, Macedonia Central Eastern Europe, South and Central All Europe and North Africa Algeria, Cyprus, Eastern Europe Central West and Meridional Turkey, Ukraine, Albania, Bulgaria, Greece, Romania Turkey Middle East, Eastern Europe, Central, Southern and Northern Asia Algeria, Morocco All Europe Western, Eastern, and Central Europe and Greece UK Italy - Sicily All Europe South of Italy, France Georgia Central Eastern Europe, South, and Central Western Europe, Central Eastern, and Southern Caucasus and Middle East Region North Africa, Middle East, South Caucasus, whole Europe Turkey, Bulgaria, Greece, Israel, Lebanon ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ 6 Advances in Agriculture Table 3: Pyrus species and hybrids originating in the Americas. Species Place of origin Pyrus americana DC Pyrus angustifolia Aiton Pyrus arbutifolia (L.) L. f. Pyrus arbutifolia (L.) L. f. var. nigra Willd. Pyrus coronaria L. P. coronaria var. ioensis Alph. Wood Pyrus diversifolia Bong. Greenland, USA, Canada USA, Canada USA USA Canada, USA USA USA, Canada Pyrus loribunda Lindl. USA, Canada Pyrus fusca (Raf.) C. K. Schneid. Pyrus sanguinea Pursh USA, Canada Canada, USA Crop ∗ he same origin. Source: USDA (2012) [5]. Pear was introduced by the English and French settlers in the United States and Canada, and in 1629, there was record of its cultivation in New England [28]. Unlike Europe, which grew via grating pears, pear in the United States was initially cultivated by seeds, which resulted in a much higher genetic variability than in Europe [31], resulting in a number of diferent varieties in America. Currently, many European pears are well established in North America; however, the U.S. genotypes cannot adapt to the climate and European soil (Table 3). In the United States, in the latter half of the nineteenth century, breeders have used the pear wild type (crosses between Asian and European pears) to their crosses, in order to obtain greater resistance to cold and “ire blight” disease caused by the bacterium Erwinia amylovora that is widely spread, though causing a large reduction in the quality of the fruit, which was repaired with successive backcrosses. he most notable diference between these junctions is undoubtedly the texture [31–33]. Wild type pears are used today as a rootstock because of their cold tolerance and adaptability to diferent environments [31]. 4. Production and Economic Importance A medium-sized fruit has about 58 calories, 6 grams of iber, and 7.0 mg of vitamin C, besides being free of fat and sodium and possessing signiicant amounts of calcium, iron, magnesium, phosphorus, potassium, zinc, copper, manganese, and phytosterols [5]. Pears, because they are part of the family Rosaceae, have sorbitol as their main translocated sugar that is converted into glucose, fructose, and sucrose. he sugar content varies greatly among Japanese, Chinese, and European pears [34]. Japanese and Chinese pears are those with higher and lower sucrose content, respectively, and the European pears are those with a high content of fructose. Pear is used mostly for fresh consumption or for the production of jams [35], being the ninth most important cultivated fruit in the world (Table 4). China is the world’s largest producer (Asian pear) and the United States is the second largest producer, being the irst producer of European ∗ ∗ ∗ Northern and Eastern Europe Center ∗ ∗ ∗ Korea, Russia, Sweden, Czech Republic, Slovakia, Germany, Latvia, Bulgaria ∗ ∗ Table 4: World production of fruit crops in the years 2010 and 2012 in tonnes. Type of fruit Watermelons Banana Apples Orange Grape Melon Fruit fresh nes Tangerines Pears Pineapples 2010 101,342,555 105,726,175 70,581,492 69,045,495 67,460,130 31,495,365 29,414,585 23,867,076 22,705,619 20,377,660 2012 105,372,341 101,992,743 76,378,738 68,223,759 67,067,129 31,925,787 31,447,977 27,060,756 23,580,845 23,333,886 FAO 2010 and 2012. pear type. Together, the top ten producers occupy an area of 1.360.230 HA annually (Table 5). he European pear (P. communis) is grown into ive major regions: Europe, North America, South America, South Africa, and Oceania, while production of Asian pear (P. pyrifolia) is concentrated in Asia. China’s pear production has increased steadily during the 1980s and early 1990s because of the expensive planting. his rate of growth generated an amount of 7.74 million metric tons of fresh pear in that time. Data show that China produces more than twice the total world production, making the crop a commodity of great importance to this country [4]. 5. Conclusion Documentation of botanists and biologists over the last hundred years was of great importance to collect the available data in this review. Undoubtedly, a fruit that produces around 24 billion tonnes per year is considered a great success in the world market. his success is mainly due to the wide commercial acceptance around the world, its nutritional importance, and Advances in Agriculture 7 Table 5: World production of pear in 2012 (tonnes) and the area (ha) harvested in the ten most productive countries. Position 1 2 3 4 5 6 7 8 9 10 Country China USA Argentina Italy Turkey Spain Republic of Korea India South Africa Japan Production (tonnes) Area harvested (ha) 16,266,000 778,582 700,000 645,540 439,656 400,600 1,136,700 22,015 26,500 35,195 34,067 25,000 394,596 14,353 340,000 338,584 299,000 38,500 13,000 14,900 FAO, 2012. its adaptability in places with large planting conditions and marketing. he recent advances achieved in the last year with the pear sequencing genome project will provide new opportunities for developing improved genotypes tolerant to biotic and abiotic stresses and also high quality fruits regarding nutritional and sugar content. he understanding of the history of pear for agriculture is of paramount importance, since scientists and students could have a better grasp of the richness of this fruit crop and its trajectory associated to humankind. Conflict of Interests he authors declare that there is no conlict of interests regarding the publication of this paper. 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