As we know it, natural rubber, for all practical purposes, comes only from the Amazon forest tree called Hevea Braziliensis. This is a situation that is going to change very quickly – a change that could affect us economically.
Hevea Braziliensis was grown on a large scale in Brazil and Peru. In Brazil it was called Para Rubber and in Peru it was called árbol del caucho. With the discovery of the vulcanizing process in 1839, the demand for Hevea latex boomed bringing massive economic gains to the areas of cultivation in Brazil and Peru. However, this lasted only till about 1940 when a leaf blight caused by a fungus decimated the plantations. The leaf blight is still active strongly enough to prevent any development of Hevea plantations in South America.
Lack of awareness
In the meantime seeds were taken out by the British to try to raise plantations in their colonies to meet their industrial needs. Around 1873, 12 seeds were germinated at Kew Gardens in Britain and sent to India for propagation, but they died. Later some 70,000 seeds were smuggled out by a British officer. Close to 3,000 seeds germinated at Kew Gardens. Of these, 2,000 seedling were sent to Ceylon and 22 sent to the Botanical Gardens of Singapore. The plants got established in both countries and were extensively propagated in Ceylon, Indonesia and Malaya. The British brought Chinese workers to do field work in the plantations in Malaya.
At present Hevea rubber plantations are found only in South Asia and South East Asia. Though Sri Lanka counts rubber as a major industry, we are not a major producer.
World rubber production stands at around 12 million tons [2014]. A breakdown of production is given below. (See Table) Dr. C.S. Weeraratna gives a lower production figure of 83,000 MT for 2017.
Natural rubber is a strategic and indispensible industrial raw material. It is essential for imparting essential properties and characteristics to any synthetic rubber. Many industries in developed countries need it without any failure in supply due to plantation or other problems that affect supply or cost. High costs of Hevea rubber have been an irritant to international buyers. There is also the serious concern that the plantations to South Asia and South East Asia too will be devastated by the fungus that destroyed plantations in South America – because the plantations in Asia are of the same species as that grew in South America and therefore equally vulnerable to the fungus. In fact, a historian has predicted in 2011 that “Southeast Asian rubber plantations will be ravaged by the blight in the not-too-distant future, thus creating a potential calamity for international industry”. Fortunately, this has not happened so far.
Dr. C. S. Weeraratna’s recent article titled “The Ailing Rubber Sector” paints a dismal picture of the status of the rubber industry in Sri Lanka as well as the failure of the programmes to develop it – not to mention the lack of awareness of global developments.
Alternative types of natural rubbers have been developed during the World Wars; however, since they did not match up to Hevea rubber, they were not developed purposefully because Hevea rubber became available soon enough after the wars for peacetime industries.
With ever increasing demand from industry, the need arose to seriously address the concerns about Asian Hevea rubber. Several natural latex sources have been studied very closely and developed during the past decade and now the developed countries have improved the quality and quantity of latex from two plants through hybridizing and possibly genetic engineering too.
These two latex types are claimed to be matching the yield and properties of Hevea latex.
The U.S.A. is already growing on a large scale a desert plant called Guayule. A company that specializes in the development of new breeds using gene sequencing techniques too to vastly improve latex yield and quality, is making rubber latex products that are free of allergy causing tendencies. They are for medical and general human use. This company is calling the new source of latex rubber “The superplant that may finally topple the Asian rubber monopoly”.
The world’s foremost tyre maker, Bridgestone is also getting vast extents of guayule grown under contracts with farmers. They too have a research laboratory to improve yield and quality.
A few years later another plant, regarded as a weed, the Russian species of the Dandelion, will also be grown on a large sale in the U.S.A. The European Union is planning to grow the Russian Dandelion on a large scale within the next three years or so.
In the U. S. A. Guayule is being grown by farmers under contract, assured of purchase. Desert lands have been opened out in thousands of acres for large scale machine cultivation, maintenance and harvesting. As a desert plant, irrigation needs too will be minimal and problems with pests could be almost non-existent.
In addition, with a lifetime of three years, partial harvesting can be done yearly or complete harvesting in three years.
Hevea rubber production
The latex is obtained by crushing the biomass, extracting with water and physical separation. The biomass residue is used as mulch, as bagasse to produce energy and fertilizer. The overall cost of production will be quite low compared to our Hevea rubber production. With a 5-7 year wait for maturing, manual tapping of each tree, tapping excluded during heavy rains, high wages for the fast diminishing community of tappers, manually collecting latex from each tree, use of chemicals to solidify latex, manually rolling out rubber sheets etc., Hevea rubber production cost is high. The good yield of latex per tree over a possible period of 25 – 30 years and the availability of timber for lumber and firewood are advantages of Hevea but they could get cancelled out. We will have the disadvantage of sea freight cost too.
Latex from Russian Dandelion must be a reality in the USA on a trial basis even now whereas in the EU large scale cultivations could start within three years. All species of dandelions are regarded as expendable weeds though they have many good uses as traditional medicines and food.
As a weed it grows under very tough conditions with long, deep growing carrot-like tubers. They are completely disease and pest resistant, propagate by themselves via dry seed broadcast by wind, require no fertilizer and mature in one year. The tuber-like roots can be dug up by machine and the land machine-prepared and planted or left to regeneration by nature.
In this case too, the tuber-like roots are crushed and the latex extracted and separated as done with Guayule. Rubber from this source could be cheaper than from Guayule.
Guayule could become a success in our dry zone. It grows better with a little rain off and on. It should do well in the planned 10,000 ha of new plantations in Ampara. Any presently unused highlands in the Mahaweli Systems too could be suitable.
The Russian dandelion is a plant that grows in the northern parts of Russia and Asia Minor. It might be possible to get it to adapt to grow in higher elevations in Sri Lanka, because the normal dandelion grew in Nuwara Eliya and higher elevations. There are many unused and virtually abandoned plantation lands under the LRC. It will do more good than harm to try out Russian Dandelion on a small scale on such land.
Both these plants do not need tappers – only operators of small machines such as two-wheeled tractors adapted for the purpose.
Source: Daily News