The Opium Poppy and relatives: Great ‘Weeds’ in every sense!
Globally, no other plant comes anywhere near the importance of the opium poppy (Papaver somniferum) of the Family: Papaveraceae, as a medicinal plant. It is, perhaps, the greatest weed, the world has seen!
Poppies are strong annual colonizers (weeds), and there are hundreds of species, both wild and cultivated. The wild ones grow fast and produce large numbers of seeds, which germinate without fuss. One would find brilliantly-coloured poppies with unmistakable and pretty flowers, often growing in harsh environments in many Eurasian countries.
The opium poppy and all its relatives have now spread widely across the world from its native range in Western Asia. It is now cultivated in many South-East Asian countries, the region being the largest producers of opium. The opium poppy has been a village-based ‘cash crop’ for centuries. Nearly 200 years ago, its industrial cultivation resulted in a major conflict — the ‘Opium Wars’ between China and Britain, arguably, a defining period of modern China.
The opium poppy is an environmental weed in Australia and an agricultural weed in the USA, Britain, and Europe. Nowadays, three poppy varieties are grown to produce commercial opium. They are Papaver somniferum var. nigrum, with oblong capsules (pods) and purple-red flowers; Papaver somniferum var. album with white flowers and round-ovate capsules; and Papaver somniferum var. abnormale, which has round capsules but small red flowers (1).
Illicit cultivation of opium poppy is by far the most lucrative industry for farmers in some developing countries. In 2010, one hectare (ha) of opium generated an income of about US $ 4,600. In contrast, lowland rice (in Vietnam, Lao, Cambodia) yielded only an average of about 2.3 metric tons/ha, worth about US $ 710/ha (ca. 6.5 times less than opium). This ratio increased 13-fold for upland rice. One can see why cultivating opium is attractive (2).
Opium (named after the Greek word opos, means, juice) is the coagulated milky juice obtained from unripe pods of the opium poppy. Dioscorides first described its collection 1900 years ago. Opium was widely used by ancient Minoans and Sumerians, during the Middle Bronze Ages (2000–1500 BC) (3).
The Sumerians (ancient Mesopotamia, 4500–1900 BC) used opium copiously. Opium played a major part in cult rituals or for healing also for Minoans, an ancient civilization of Eastern Mediterranean and the island of Crete (2700– 1500 BC). Minoan ornaments and jewellery depict poppy capsules implying multiple symbolic meanings of opium use for healing, fertility, wealth, and immortality. The presence of poppies in archaeological objects from the Mycenae (ancient Greece, Bronze Age, 1600–100 BC) also suggests a long tradition of using opium in the ancient world (4).
In the epic story — the Odyssey (5), opium is mixed in a wine-based drink called Nepenthes (Greek ne: not, penthos: sorrow) and given to soldiers before combat, to dull the horrors of battle. The infamous Roman Emperor Nero appears to have used a mix of hemlock (Conium maculatum) and opium to murder his stepbrother Britannicus, in 50 AD (3).
A few days after the petals fall, the unripe, greenish pod is shallowly slit with a knife. The milky juice flowing from the cut rind coagulates in a few hours to a gummy material, which is then scraped off and cleaned to make opium. Opium harvesting occupies armies of men, women and children in Turkey, Macedonia, other Balkan countries, Romania, Bulgaria, Iran, China, and India. Opium production is also common in South-East Asia’s ‘Golden Triangle’ (Thailand, Lao and Myanmar).
Opium’s valued qualities are due to its alkaloids. The total alkaloid content in opium is 10–20%, comprising about 40 alkaloids. The most important one is morphine, the greatest pain alleviator the world has ever known, named after the Greek god Morpheus, the creator of sleep and dreams.
Six opium alkaloids, which occur naturally in the largest amounts are: morphine, narcotine, codeine, thebaine, papaverine and narceine.
Of these, three are phenanthrene alkaloids and are under international control: these are morphine, codeine, and thebaine. They are all three used in the drug industry, thebaine usually for conversion into some derivative which is more useful medically. Of the other three, not under international control, narcotine and narceine have scarcely any medical or other uses. Consequently, the four economically significant alkaloids of opium are morphine, codeine, thebaine and papaverine.
Heroin (diamorphine), the highly addictive narcotic, is produced from opium. Codeine, which does not induce addiction, is the second most crucial medicine from opium. Codeine is the key ingredient in cough syrups and other sedative mixtures. Paregoric, once a favourite medicine for children, is camphorated opium tincture. While only the capsule juice of the poppy is narcotic, no other parts of the plant are. In Western countries, the seeds are commonly sprinkled on rolls or buns, and the oil pressed from them (maw oil) is a common adulterant of olive oil.
To date, opium remains the only commercial source for morphine and codeine. Collectively called ‘opiates’, they depress the central nervous system. Pethidine, methadone, and several other painkillers are synthetic morphines. Their importance in medicine, in relieving pain and in saving lives (methadone), needs no special emphasis.
Two of the opium poppies, famous for their vibrant coloured flowers, are the ‘Flanders poppy’, also called the ‘scarlet corn poppy’ (Papaver rhoeas), and prickly poppy (Papaver argemone). Both are closely related to the more notorious Papaver somniferum. Greek mythology says that poppies flowered along the banks of a river, from which the dead had to drink to forget their former existence in the living world. Death, sleep, and dreams are closely intertwined with the opium poppy, as the Greek gods Hypnos (Sleep) and Morpheus (Dreams) call upon opium to cast their spells (2).
The Greek poet Homer (ca. 750 BC) (5) associated the drooping poppy with the form of a dying soldier, and the anguish of war. At a banquet in Sparta, Helen eased the Trojan War grief of her guests by spiking their wine with honey and a herb (presumed, as opium). In the ancient world, the opium-induced euphoria masked the pain of everyday living, soothed painful memories of war, and eased the passage from life to death (3).
Today we associate poppies with the World War I Remembrance Day. Millions of people across the globe remember the fallen soldiers in the Great War, wearing flowers of Papaver rhoeas on this day, as a mark of respect.
Several poppies are known in Eurasia and North America for their ubiquitous abundance in freshly churned fields and spectacular blooming across disturbed lands, such as battlefields. After the Battle of Waterloo, the mass graves of Napoleon’s soldiers were rapidly smothered by scarlet poppies.
A local myth soon arose that it was the blood of the dead which added lustre to the crimson sheen of the battlefield. The Scarlet Corn poppies were imagined as the spirits of the dead rising from the blood-drenched earth in many European battlefields including Flanders and Somme. As a result, the poppy quickly became a metaphor for the dead (6).
More realistically, the prolific seed production in poppies was the reason for its abundance in those scarred fields of death. The disturbed ground were ideal for the growth of the colonizer. In the blood-drenched battlefields, the soporific values of the poppies also prompted their use for reducing pain and suffering. The poppy induced narcosis and, in some cases, assisted the mortally-wounded on the ‘long sleep’ of death.
From a Weed Science perspective, as far as I am concerned, the poppy epitomizes medicinal weeds. No other single plant comes anywhere near in terms of providing for humanity compounds of medical utility as pain-relievers and anesthetics.
References
1. National Academy of Sciences (NAS, USA). (2011). Feasibility of Using Mycoherbicides for Controlling Illicit Drug Crops. (http://www.nap.edu/catalog.php?record_id=13278).
2. Duke, J.A. (1973). Utilization of Papaver. Economic Botany, 27 (4): 390–391.
3. Askitopoulou, H., et al. (2009). Archaeological evidence on the use of opium in the Minoan world. The history of anaesthesia. International Congress Series, Vol. 1242, pp. 23–29.
4. UN Office on Drugs and Crime (https://www.unodc.org/unodc/en/data-and-analysis/bulletin/bulletin_1953-01-01_3_page005.html).
5. Homer — The Odyssey. Translated by Samuel Butler (1921). See page 64 (https://www.planetebook.com/free-ebooks/the-odyssey.pdf).
6. Military History Monthly (https://www.military-history.org/articles/in-flanders-fields-a-history-of-the-poppy.htm).
