[ Etude ]

Cannabis et génétique

Honnêtement j'espère qu'on leur enverra les produits de certains breeder européen pour voir si ça triche beaucoup

C'est pas gagné.

ACDC is a popular CBD-rich variety. While many of our ACDC samples are in a similar place in the galaxy, some are genetically distinct.

Une petite étude qui permet de mieux visualiser la migration de la plante sur la planète avant de regarder comment les génétiques du commerce traversent l'Atlantique.

Physical evidence for the origin and diffusion of Cannabis in Asia

            "Many cultivated plants are so changed from their ancestral types that it is not possible to unravel their evolutionary history. Such is not the case, however, with Cannabis. Yet, despite its long history as a major crop plant, Cannabis is still characterized more by what is not known about its biology than what is known (Schultes and Hofmann 1992)."

    This situation, however, is changing. Work by Vavilov (1987) has shed light on how Cannabis may have been originally domesticated. It is well known that Cannabis requires soil with a high nutrient content, either artificially fertilized or naturally occurring. By working with wild hemp growing in Mongolia, Vavilov imitated the process of selection and domestication of hemp as it may well have occurred 6500 years ago.
        Vavilov postulated four stages in the domestication of Cannabis: (1) existence of plants entirely in their wild state, (2) initial colonization of the wild plant on nutrient-rich dump heaps, (3) utilization of the weed by local inhabitants, and (4) intentional cultivation (Vavilov 1992). Unlike oats and rye, which required an intentional effort to locate and utilize, hemp was very likely only circumstantially domesticated. Domestication probably occurred independently in several centers in northeast Asia around six millennia ago (Vavilov 1987, Schultes 1970, Li 1973 and 1974).
        Due to biological data in English translation being recently released from China and India (Harlan 1986), details of the centers and exact dates of Cannabis domestication vary. We were able to locate little palynological data for the Asian continent (Figure 3). Only Chou (1963) reveals a pollen curve for what he interpreted as Humulus at Pan-p’o, China dated to ca. 4500 BP. Recently, Garg (1996) has found Cannabis pollen in the pollen loads of bees in present-day northeastern India. As a result, we rely largely on archaeological evidence. It is widely accepted that the Chinese were the first to domesticate this native Asian plant. There is strong archaeological evidence of its widespread use as an economic crop by ca. 6500 BP. Existing records place its major center of domestication in present-day northern China where there is a continuous record of its use from the Neolithic to the present (Li 1973). While its use as a food source probably resulted in its initial domestication, Cannabis fiber was discovered not long thereafter.
        In ancient China, hemp cords were used to form the core of clay temple statues. Remains of Song Dynasty (ca. 1040 to 720 BP) statuary made with hemp cordage have been excavated near Chin-Ch’eng in Shanxi Province (Kao 1978). Hemp textile, rope and thread remains were also reported from a Liang-Chu culture site in Zhejiang Province (Cheng 1966). Hemp textile remains have been discovered at a Shan Kingdom (ca. 3520 to 3030 BP) site in Anyang in Henan Province (Chang 1963). Zhou Dynasty (ca. 3200 to 2219 BP) cemeteries in Anyang, and also Changsha in Hunan Province, yielded thousands of funerary objects, and the inventories listed included hemp textiles (Cheng 1963). A Zhou Dynasty tomb in Shanxi Province contained hemp cloth of a light weave, indicating that hemp weaving had reached a fairly high standard (Li 1974). Excavations of Han Dynasty (ca. 2100 to 1900 BP) tombs in Gansu Province produced complete specimens of hemp cloth used to cover corpses. The coverings were wrapped around silk dresses and were tied with hemp ropes. Hemp fibers were also used for reinforcing the plaster covering of the brick walls of the crypt (Kansu Museum 1972). Laquerware winged cups constructed over hemp cloth cores were recovered from a Han Dynasty (ca. 2100 to 1900 BP) wooden pit burial near Nanchang city, Jiangxi Province (Kuo 1978). A boat coffin recovered from the Wuyi mountains in Fujian Province and carved from a single tree trunk contained the body of an old man wrapped in cloth funeral shroud said to be made of jute, hemp, silk and cotton. The coffin was dated at ca. 3600 to 3300 BP (Li 1984). Fragments of both silk and hemp textiles dated to ca. 2655 to 2615 BP were found in a tomb excavated in Anhui Province adhering to the outer surface of bronze sculptures indicating that the bronzes had been wrapped in cloth (Yin 1978). Many other textile samples identified as "hemp" have been recovered from additional sites across China, but these are undated and have been omitted from this survey.
        China is the original home of paper making, and paper scraps containing hemp fibers have been discovered at Chinese archeological sites. Li (1974) and Temple (1988) both report on the 1957 discovery of a scrap of paper in a tomb near Xi’an in Shaanxi Province dated at ca. 2138 to 2085 BP. This is considered to be the oldest surviving piece of paper ever recovered from a dated site. Temple (1988) describes the piece of paper and explains its fabrication,

    "It is about 10 cm square and can be dated precisely between the years 140 and 87 BC [ca. 2138 to 2085 BP]. This paper and similar bits of paper surviving from the next century are thick, coarse and uneven in their texture. They are all made of pounded and disintegrated hemp fibers. From the drying marks on them, it is evident that they were dried primitively on mats woven as pieces of fabric [also likely hemp], not on what we know as paper molds. In these early days, the water just drained slowly through the underlying mat of fabric, leaving the paper layer on top. This was then peeled off and dried thoroughly. But so thick and coarse was the result, that it could not have been very satisfactory for writing."

        Li (1974) describes a much later find of hemp paper along with other hempen artifacts at Turfan in Xinjiang Province in western China,

    "In one grave was found a rare fragmentary script of the Lun Yü (Analects of Confucius) written in 716 AD [ca. 1282 BP] on white hemp paper. Also found were paper shoes made of pasted layers of white hemp paper sewn together with white hemp threads. In the same grave was a complete cloth sheet of hemp fabric.

    "In another grave dated 721 AD [ca. 1277 BP], there was hemp cloth as well as hemp shoes. The latter were of two kinds, one woven of hemp fibers and the other sewn in a fine yellow cloth."

        China has produced fewer seed remains than fiber remains and fiber impressions. Li (1974b) describes the tomb of a woman from Han Dynasty Tomb No. 2 (ca. 2100 to 1900 BP) at Changsha, Hunan Province,

    "Besides fruits such as pears, peaches and jujubes, there were grains such as rice, wheat, millet, hemp seed, and mustard seed. Hemp seed was clearly used in early Han times as a common grain along with the other cereals."

        The most well publicized, as well as the most controversial, Cannabis seed remains (Figure 2) were recovered from the frozen tomb of Iron Age (ca. 2430 BP) nobles of eastern Siberia discovered by Sergei Rudenko in 1929 (Rudenko 1970). We have included Rudenko’s account of the occurrence of Cannabis seeds in the tomb, even though much of it is highly conjectural.

            "Thus in barrow 2, two smoking sets were found: vessels containing stones that had been in the fire and hemp seeds; above them were shelters supported on six rods, in one case covered with a leather hanging and in the other case probably with a felt hanging, large pieces of which were found in the southwest corner of the tomb. Finally, there was a [leather] flask containing hemp seeds [Figure 2] fixed to one of the legs of a hexapod stand. Consequently we have the full set of articles for carrying out the purification ritual, about which Herodotus wrote in such detail in his description of the Black Sea Scyths. There had been sets for smoking hemp in all the Pazyryk barrows; the sticks for the stand survived in each barrow although the censers and cloth covers had all been stolen except in barrow 2. Hemp smoking was practiced evidently not only for purification, but in ordinary life by both men and women.

            "In each vessel besides the stones, as already mentioned above, there was a small quantity of seeds of hemp (Cannabis sativa L. of the variety C. ruderalis Janisch.). Burning hot stones had been placed in the censer and part of the hemp seeds had been charred. Furthermore the handle of the cauldron censer had been bound round with birch bark, evidently because the heat of the stones was such that its handle had become too hot to hold in the bare hands."

        Rudenko’s speculations on the smoking of Cannabis by these Iron Age nobles, based largely on Herodotus’ accounts of the Scythians of the Black Sea region, have led to many claims that the Scythians smoked Cannabis. Clarke (1998) provides a more complete rebuttal of these claims. All that we know with certainty is that Cannabis seeds were found in the Pazyryk tombs. Woven textiles were also recovered, but the identity of the fibers has yet to be determined (Clarke 1995).
        Cannabis remains may also have been recovered from more recently excavated Iron Age tombs similar to the Pazyryk tombs discovered by Rudenko. In 1993, a tomb containing the preserved body of a young woman nicknamed "The Lady" or the "Frozen Princess" was discovered by a Russian team headed by Natalia Polosmak. The tomb dated at ca. 2400 BP reportedly contained many grave goods, including either Cannabis remains in a small pot (Anon. 1994) or coriander seeds in a stone dish (Polosmak 1996). It is not clear if the seed remains were of Cannabis or coriander or both. Polosmak (1996) also echoes Rudenko’s (1970) theory that the Pazyryk people may have breathed the fumes of burning Cannabis.
        Nearly all of the remaining early fiber impressions attributed to Cannabis hemp originate from China. Li (1974b) mentions several sites in China where cordage impressions deduced as being Cannabis were recovered from various sites of the Yang-Shao culture in northern China dated ca. 4410 to 3100 BP and from a late Neolithic age (ca. 5000 to 4000 BP) site in Henan Province in eastern China.
        Additional evidence of cord impressions have been recovered from early Neolithic (ca. 6000 to 5000 BP) sites on Taiwan island. According to Cheng (1959), referring to the lower stratum of Yuan Shan, the richest and most important site on the island,

    "The characteristic remains here as elsewhere on the island, are the cord-marked pottery, a coarse sandy ware, handmade, thick-walled, with a plain surface covered with cord marks and, occasionally, with lineal impressions. . . . There is also a stone beater, a rod-shaped implement with incisions, which might have been used for the lineal impressions in pottery decoration, or for pounding hemp fiber, a common raw material for rope and textile."

        Textile imprints have been found in pottery shards, clay layers and bronze objects. Anderson (1923) surmised that woven textile impressions found on Neolithic (ca. 6000 to 4000 BP) pottery shards at Yangshao in Henan Province represented hemp cloth. Li (1974b) cites many finds of Cannabis textile impressions from China. At the early Neolithic Yang-shao site at Pan-p’o, near Xi’an in Shaanxi Province, imprints of textiles were found on many pottery shards dated to ca. 6225 to 5430 BP. Another Yang-shao site in Shaanxi Province yielded pottery spinning whorls, fine bone needles and textile impressions in the dirt of one grave and were interpreted as hemp re-mains. Bronze weapons of the Shang Dynasty (ca. 3764 to 3120 BP) recovered from excavations at Anyang, Henan province, have impressions left by cloth wrappers thought to be hemp. A dagger recovered from a ca. 2900 to 2800 BP burial at Ning Xian, Gansu Province was apparently wrapped in hemp or a similar coarse fabric as indicated by fiber impressions (So and Bunker 1995).
        By ca. 3000 BP, Cannabis had most likely migrated west and south over the Himalayas and into India, probably coming with nomads and traders over the trade routes that crossed the region. In light of the accepted antiquity of Cannabis in India, it is noteworthy that no Cannabis re-mains have been recovered from archeological sights there.
        Although archaeological and historical data provide a foundation for our understanding of Cannabis dispersal in Asia, there remains a severe lack of palynological and archeological references with which to correlate these data. We were not able to find many references dealing with analytic evidence of Cannabis pollen for the entire Asian region and no archeological finds of Cannabis remains at all from southern India. Certainly, archeological sites have been investigated, but translations of foreign studies appear to be rare. This may simply be the result of researchers focusing their investigations on other topics besides Cannabis remains. Many early excavations overlooked botanical evidence in their search for cultural objects. Long core samples dating further back in time may reveal Cannabis pollen grains giving us a much earlier time scale for the origin, evolution and migration of Cannabis. This is an area worth pursuing and will help broaden our biological and historical knowledge of this important crop plant.

http://www.druglibrary.net/olsen/HEMP/IHA/jiha5208.html



heu mieux visualiser... ou pas, au contraire. Voire le point d'interrogation.



Pour les dates :

La locution « avant le présent »1,2, en abrégé A.P. ou AP (de l'anglais Before Present1,2, en abrégé B.P. ou BP1,2), est utilisée, en archéologie, en géologie1 et en climatologie2, pour désigner les âges exprimés en nombre d'années comptées vers le passé à  partir de l'année 1950 du calendrier grégorien1, voire symboliquement à  partir du 1er janvier 19502. Cette date a été fixée arbitrairement comme année de référence et correspond aux premiers essais de datation par le carbone 14. Cette date est également légèrement antérieure aux premiers essais nucléaires qui ont perturbé la répartition d'isotopes utilisés en radiochronologie1,3,4.

La mention « avant le présent » ou « BP » s'applique généralement aux dates obtenues par des méthodes de datation absolue, comme les dates déterminées à  partir du carbone 14Note 1, mais aussi aux dates obtenues par d'autres méthodes (thermoluminescence, uranium-thorium, etc.) pour des périodes plus anciennes (Paléolithique inférieur et moyen).

Pour les périodes très anciennes, voire pour les périodes géologiques antérieures à  l'apparition de l'homme, la mention BP est généralement sous-entendue : en effet, la différence de 1950 ans entre un âge BP et un âge avant J.-C. n'est pas significative par rapport aux marges d'erreurs obtenues pour les périodes en question.

Pour les périodes récentes de la Préhistoire (Épipaléolithique, Mésolithique, Néolithique) et pour les périodes historiques, il est nécessaire de corriger les imprécisions des dates obtenues par la méthode du carbone 14, de les étalonner.

Dernière modification par Mister No (16 septembre 2016 à  13:35)