Contribution of science and technology for a sustainable natural rubber economy
It had been forecasted by a global rubber group that by 2012, a glut of Natural Rubber (NR) would be produced in the world, possibly by the new clearings coming in to bearing mainly in Vietnam and Thailand while the consumption of NR was expected to decline due to the ongoing recession in US and in the EU. According to this data, this glut is expected to continue until about 2017 and hence, a slightly more depression period is expected in the NR price in the next couple of years too.
However, according to a report in the Rubber Economist Ltd, world NR consumption is poised to increase this year and next year diminishing the surplus and thereby boosting the rubber price to $3.5 per kg by the end of 2014. Whatever it is, the international rubber prices are beyond the control of farmers. Early during the last few decades, attempts were made by the scientists all over the world to convert NR to derivatives like Chlorinated rubber, cyclised rubber, epoxidised natural rubber, etc to replace synthetic counterparts used in the industry in order to get more attractive prices for such grades of NR. Those attempts were not very successful. Hence, what the NR growers should do now to maximise their profits from the prevailing rubber prices is to cut down the cost of production (COP) of all grades of rubber at the level of the rubber farms using the latest developed technology.
The main factor determining the COP of raw rubber is the productivity or the yield per hectare of rubber lands. In Sri Lanka some of the RPCs (plantation companies) have been able to prove that, if the productivity is increased to 1200 kg/ha/yr the COP drops down to Rs 180/kg compared to the average estate COP of Rs 250/kg.
Similarly, If the productivity is increased further to 2500 kg/ha/yr, COP can be lowered further to Rs 100/kg. Hence, even at the prevailing NR prices in the international market today, over 100 per cent increase in profitability can be achieved with this level of land productivity.
In order to achieve a productivity of about 2500 kg/ha/yr, scientifically proven correct agronomic practices that should be adopted at the farm level are:
1. Maintaining a stand of 475 to 500 healthy plants per hectare in new clearings at the time of marking trees for harvesting. In order to achieve this stand:
(a) Special care must be taken in land preparation to minimise white root disease damage, which is the main cause for mortality of young plants thereby lowering stands. On average this results in a 10-15 per cent drop in SPH.
(b) Planting 500 quality young budded plants per Ha at the onset of the monsoon to minimise mortality during dry months.
2. Regular fertilizer application, weeding and disease management to maintain an annual girthing of 10 cm in new clearings.
3. Draining, terracing and cover crop management to conserve the fertile top soil and the moisture levels in the soil.
4. Poor performing plants need to be treated differently, i.e. split fertilizer and compost application, to enhance their growth to be in par with the more vigorous plants. Infilling of dead plants and replacing runts during the first year with jumbo plants and in the second year with stumped buddings.
5. Not to commence tapping in new clearings until the girth of 60 per cent of the stand reaches 50cm.
6. Low frequency tapping with four Ethrel applications while having rain guards. This will help to minimise the shortage of tappers also to a great extent whilst enhancing the harvester productivity.
(Apart from that, all latex stimulation techniques tried out using ethane gas have not shown any positive improvement on rubber yields, in Sri Lanka).
7. Use of rain guards to minimise rain interference on tapping rather than undertaking recovery tapping leading to poor quality of tapping and high percentage of dry trees.
Now a day’s weed control in estates is a big problem in Sri Lanka; mainly because the commonly used weedicides have been banned by the health authorities. Manual weeding is also expensive due to escalating labour wages. Hence, the use of power mat made out of waste material introduced by the RRISL is worth considering as an alternate way of weed control and moisture retention.
If these measures are taken, obtaining a yield of 2500 Kg (5 Kg/tree) is not difficult.
Precautions to be taken during processing
When it comes to processing, regular documentation of chemicals used helps to minimise the wastage of chemicals, which is not only affecting the COP, but also lowers the quality of the rubber (particularly white crepe rubber) produced. Damage caused to the environment by the effluent water is also minimised. Hence following the ISO 9000 regulations too helps to cut down COP of raw NR while helping to minimise the damage to the environment.
Another important matter helping to sustain the industry is cutting down the cost of drying. In this aspect, use of alternate sources of fuel like saw dust, and shortening the drying time of rubber, particularly RSS using the RRISL’s newly developed smoke house drying system is also important.This system not only minimises the cost of fire wood used for drying RSS, but also tremendously improves the colour of the RSS produced.
If these measures are undertaken, even under the slightly dropped price of NR in the world market that is expected during the next couple of years, rubber farmers can still make a substantial profit, for a comfortable living.
Further, it should be specially emphasised here that at this juncture rubber farms should not be converted to other crops like oil palm. This is the period in which all plantations must start replanting old fields to bring new areas into tapping by 2018, by then the rubber prizes are expected to rise up to about $6 per kg. This is the correct strategy always followed in other rubber producing countries, particularly Malaysia. If not when prices are booming in the world market we will not have sufficient rubber even to run our own rubber product industries which brings in lot of foreign exchange to the country and provides employment to a large number of Sri Lankans. Alternate crops can be planted in lands not utilised for any agricultural purposes in the intermediate and dry zones in Sri Lanka.