Jat/Clones, Cultural Practices and Processing
Rubber is one of the most important cash crops, with multipurpose uses. It is produced from the latex of rubber trees (Hevea brasiliensis (Willd. ex Adr. De Juss.) Muell. Arg.), an exotic deciduous rain forest tree species of Family Euphorbiaceae. The British planters first introduced it in Bangladesh in the early twentieth century. But commercial plantation was started in 1961 by the government in Chittagong and Sylhet hilly regions. Later on, plantations were expanded in Chittagong Hill Tracts and Madhupur by the government and public enterprises. The British and some other private companies also planted rubber in the fellow lands of tea estates. At present about 25,000 hectare of land is under rubber plantation in Bangladesh, and annual production is about 7,500 tons against 20,000 tons country’s total demand of natural rubber (NR). Although production of NR is far less than the demand still the price is very low, even less than the cost of production, due to competitive low price of NR and synthetic rubber (SR), a bi-product of crude oil, in the international market.
Considering high productivity, storage, transportation and marketing facilities, the government encouraged its plantation with financial support; land allotment and foreign technical assistance. Public and private enterprises established plantations in different hilly regions and commercial exploitation started successfully within seventh years of plantation. The growth and latex flow is also very encouraging. Since maintenance and processing cost is relatively very low and a good price of rubber prevailed till 1996, it was considered an important crop with high potentiality.
Prospects and Uses
It should be mentioned here that, natural rubber is the raw material for tyres and tubes of automobiles, bi-cycle and rickshaw, footwear, belts and hoses, latex foam, cables and wires, battery boxes, gloves, coats and aprons, air bags, life jackets and life buoys, adhesives, balloons and toys etc. and it is also essential for processing synthetic rubber. Therefore, the future of rubber is very bright.
Besides rubber, rubber plants have many other uses e.g.:
1. Timber: After economic exploitation of rubber for about 30 years its timber will be a good source of furniture timber.
2. Rubber seed oil: Rubber seed kernel is used for extraction of oil, which is abundantly used as lubricant, and for soap and paint industries and the cake as a good fertilizes and poultry feed.
3. Honey: Mature rubber plantations are the potential source of honey. Honeybees collect large quantities of nectar from extra floral nectarines at the swollen tip of the petiole.
4. Affluent or latex processing wastes and residues can be used as fertilizer and making biogas for power.
5. Land improvement: Every year fallen leaves add 6 to 7 tons per hectare of biomass. Moreover, rubber roots make a very good net spreading in the top soil up to a depth 1 to 1.5 m and increase the porosity of the soil.
6. Carbon sink: Rubber is a very preferred fast growing multipurpose species for quick afforestation. It acts, as a good ‘carbon sink’ will be helpful in reducing global warming.
7. Ecofriendliness: Rubber plantations have a green image and are inherently environment friendly. Properly managed plantations are self-sustainable ecosystems and could maintain a fair degree of biodiversity. Rubber plantations do support different plant species.
Yield and productivity
A well-managed plantation in the traditional zone can produce 3 tons rubber per hectare. The average yield of rubber is about 1.6 tons in India. But in our non-traditional condition we have achieved about 0.5 ton/ha only. Unfortunately, the industry suffered badly in the last decade with the decreasing price in the international market, and import of low priced natural and synthetic rubber through free market economic policy. Moreover, low productivity due to lack of proper cultural practices and appropriate processing facilities aggravated the situation further more. New investment for extension of plantation and maintenance of existing plantations was becoming discouragious.
For development and expansion of rubber, systematic research and protection of market price were not done. As a result, the industry became a loosing concern and thousands of workers were not getting wages in time. Plantation investment, expertise and skillness, and dependency on the job were in a serious position. The rubber industry was facing destruction although there was a great demand for NR in Bangladesh. In this situation, the government should take necessary measures to save the plantation industry considering its contribution in land utilization, afforestation, and development of environment and in national economy. Nevertheless, a huge investment of foreign currency from Asian Development Bank (ADB) and World Bank was made for the industry.
However, the situation has been changed now, the price of rubber has been increased at least three-folds, at a very encouraging level. Now rubber is one of the most profitable commodities in the present market. Therefore, it is the right time to think forward for further development revising the policy and rectifying the faults through applied research and appropriate technology to achieve highest productivity and profit.
Goals to achieve
To achieve the following goals, prime importance should be given on rubber plantation:
1. Crop diversification and employment opportunity
2. Land utilization and soil improvement
3. Quick afforestation and carbon sink for mitigation of global warming
4. Creation of environment friendly self-sustainable ecosystems
5. Increase of production and yield at least two folds by next 10 years and high cash return
6. Highest possible exploitation period
7. Good quality rubber production
Identification of problems and strategy for their solution
However, an attempt has been made to discuss the cultural practices and economic policies for development of rubber plantation industry. In this study, some key points for improvement of this plantation crop, analyzing the existing problems and their solutions are highlighted. The low yield may be for the following reasons:
1. Selection of Jat/Clones
2. Low productive SPH (stand per hectare)
3. High tapping interference
4. Lack of uniform productive stand
5. Prolong dry season
6. Cultivation practices
Multipurpose uses are specially considered to attain highest productivity, land uses and improvement of soil health available for succession of more productive crop. It is very essential to establish other shade loving crops or creepers viz. turmeric, corms, cassava, and piper etc., in rubber plantation for economic and ecological benefit.
Selection of clones
Rubber plants were introduced in Bangladesh from Malaysia for commercial plantation. Both seed and grafted saplings of different clones e.g. GT 1, PB 235, RRIM 600 and TJIR etc. were imported and planted without any field experiment in our condition. Moreover, RRIM 600 became dominated although it is not widely accepted for large scale planting due to susceptibility to Phytophthora sp. and low initial yield.
However, RRII 105, RRIM 703, RRIM 600, GT 1 and PB 235 are recommended for multiclone planting without exceeding 50% area by a single clone, in our conditions considering yield, severity of diseases, wind effect and drought. Since rubber timber is recognized as good furniture timber, the recently developed ‘Latex-Timber’ clones e.g. RRIM 928, RRIM 929, RRIM 931, RRIM 2001, RRIM 2002, RRIM 2014, RRII 5,and RRII 203, RRII 207 and RRII 214 can be preferred for their above average yield and good quantum of timber. Very recently higher yielding clones viz. RRII 414, 417, 420 and 430 are developed in India those can produce 20 to 50% more rubber than RRII 105 and RRIM 600.
Propagation and plantation practices
Clones were propagated by bud grafting methods. Both green and brown budding techniques were followed as per advice of foreign consultants without any adaptability study. Green budding was followed by most of the plantations in government sectors but the suitability of the budded plants is not good for plantation as the plants are planted in the following year when they are too big. Although big plants are easy to maintain but their growth is very slow and maturity is delayed for about two years. The mortality percentage is also high, resulted low stand per hector (SPH). Since gap filling (infilling) with big plants is difficult the plantation becomes uneven with low productive stand. Gaps filled with budded stumps seldom succeeded for production and this was only wastage of money.
Brown budding was followed after the suggestion of Sri Lankan expert in some multinational companies and it was considered to be the right method for raising grafted plants for plantation in right time. But due to less skillness in brown budding in October prior to dry winter the success was very low, even less than 50%. For that reason, plantation could not be established as per target due to shortage of sufficient planting materials.
The above problems can easily be solved or minimized by adopting appropriate budding technique ‘Young budding’ of rootstock plants of seven to eight-week-old, raised in bags, with the bud from desired clone. By this technique, the plants will be ready for plantation within seven months. This is regarded as the most suitable method in our condition to reduce cost of plants, save time and good quality plantable plants.
Gap filling with advance planting materials (APM)
It is already mentioned before that, gap-filling work is almost unsuccessful for the following reasons:
1. Advance planting materials (APM) were not ready as per required size.
2. Gap filling work was done in late season, growth retarded or died during dry season.
3. Budded stumps did not achieve required height with 2.4 to 2.5 meter brown stem before trenching, tailing and transplanting.
4. Due to lack of proper attention the survived plants could not compete with the other plants and become unproductive runts.
Spacing and plant population are also misguiding factors for low yield. Different experts are of different opinions. Although some of them consider the landscape, some not. But most of them ignored the positional effect of the latitude, the inclined sunshine in most of the year. Plantation spacing 4.26X4.57 meter suggested by some experts is totally impracticable and will lead to low productive stand from early stage of tapping. Competition for sunlight will make them taller without achieving desired girth for tapping. It will be difficult to reach sunlight to the soil and ground cover will perish and erosion will take place. Soil nutrients will also wash away with the monsoon rain and superficial roots will expose. According to Indian researchers an optimal population of 310 nos. of trees per hector at 10th year of planting gives maximum yield. Therefore, the stand with 512 nos. trees cannot be optimum in our environment. Although some experts opined that natural calamities would reduce the stand, therefore, initial high population will be helpful to maintain desired yield. But in practice it is observed that such damage cannot bring down the stand uniformly but the population remains thick in some areas and very low in some places resulted very low yield.
The spacing and SPH should be maintained considering the sunlight, undulation, face of the terrain and the latitude. It is important to ensure that adequate space is provided for each plant so that there is good exposure to sunlight for development of the aerial portions and sufficient volume of soil for spread of root system. In addition to the direct influence on growth and yield, the planting density can affect the duration of immature period (Westgarth and Buttery, 1965). Bark thickness; bark renewal and panel diseases, are also influenced by planting density (Napitupulu, 1977; Leong and Yoon, 1982; Webster, 1989). Planting density also determines the yield per tapper and the cost of tapping (Barlow and Lim, 1967). The spacing depends on the latitude, height of the trees width of the canopy and slope and face of the terrain. The recommended optimum density and spacing in our condition is given below:
Landscape or terrain Spacing (meter) Plant population (SPH)
Flat areas 6.5m X 3.5m = 440 Nos
Hills or Tillahs 7.5m X 3.0m = cheap drugs without prescription 445 Nos.
8.0m X 2.75m = 455 Nos.
Uniform density plantation can ensure aerial surface area more or uniformly. This can be done by measuring the standard slope of the hills and calculating the contour distance with simple formula AC² = AB² + BC². Plant to plant distance can be calculated dividing the standard planting population (SPH) by the standard contour distance. However, close spaced plantation is needed in the valleys and in the wind prone areas.
Up keeping at least first three years to get a straight un-branched bole for good tapping panel up to 2.4 meter high.
Gradual thinning out of the weak plants should be done from 4th year up to 10th year of plantation. Although it is a difficult task but it must be done, otherwise most of the trees will remain non-productive. This practice should be followed under close supervision, otherwise illicit felling for making wood fuel can destroy the plantation. Pruning or lopping of suppressed and tertiary branches should be done in January to reduce the canopy weight to enable the trees withstand in strong winds. It is always suggested to remove the stumps of the broken trees whose persistent leaves encourage diseases like Powdery mildew and leaf spot disease.
Wind breaks or shelter belts
As the rubber plantation was made with pre-fixed SPH that maintained for production period, the competitions for growth and survival is less than the plants grow in the natural forests. For that reason imbalanced growth of rubber plants resulted low withstanding capacity against storm and cyclones. In 1991, the plantations of the government and private and small holders of Chittagong region suffered badly due to cyclone. The advisors did not consider the severity of the wind effect and they forgot to establish wind barrier across the wind prone belts. Therefore, it is mandatory to establish windbreaks in plantations in wind prone tropics.
Erosion and degradation of soil
Rubber planted in large area as a monocrop. Natural flora and fauna were disturbed due to use of pesticides, herbicides and organic and inorganic fertilizers. To establish plantation, initial use of herbicides in large scale, not only the growth of the plants become retarded but the ground covering plants were perished or killed and resulted heavy erosion of the topsoil. Moreover, since rubber is a deciduous plant defoliated leaves cover the ground and obstruct the growth of vegetation in the rubber area. Therefore, it is very important to establish other shade loving crops or creepers like turmeric, corms, cassava and piper etc. in rubber plantation for economic and ecological benefit.
Although it is a recommended practice to make terraces along the planting rows on the contours of the hilly areas for conserving moisture and erosion control, and of course for easy movement of the tappers, it is practically found that the terraces are not maintained in effective manner and thus creating more problems in soil and nutrient conservation. Moreover, uncut narrow earth blocks and silt pits are also neglected. In some plantations, terracing is not done at all to reduce the initial planting cost or due to lack of knowledge about the benefits of the terrace.
Pests and predators
As an exotic monocrop certain microbial and entomological diseases like pink disease, powdery mildew, grubs, caterpillar and slugs etc. were also introduced and their severity are increasing day by day. Due to change of natural flora and fauna, biological control by the predators is very limited. Certain plants e.g. tea and eucalyptus act as alternate host of certain pathogens. For that reason, barriers with other species should be raised between those plantations. It is worthwhile to note here that, this barrier plantation can be used as future wood fuel for smoking rubber. Moreover, plantation with different species can also help in the improvement of environment by creating food and shelter for wild animals (mammals, birds and reptiles etc.).
Scarcity of skilled tappers
Due to uneven distribution of crop, a common standard for payment of wages still cannot be achieved, as it is done in the rubber producing countries like Malaysia, Thailand and Sri Lanka of the traditional zones. Very limited training facilities for the tappers, still exist here. Only a training institute is located in Chittagong Hill Tracts for the government gardens, which should be more organized with modern equipments and facilities. Proper arrangement for training is urgently needed for the private sectors. Other agricultural cropping, sometimes creates acute shortage of work force for rubber production.
However, keeping extra tappers at least 5% can minimize absenteeism problem, but during the acute scarcity it is advisable to use yield stimulants e.g. ethephon, ethrel and edbroza etc., which will reduce the tapping frequency and can minimize the tappers’ requirement.
Bangladesh is situated in non-traditional rubber production zone where more than four months are dry or with very little or no rains. Therefore, in this period dry rubber content (DRC) decreases as low as 15%. On the other hand, during the rainy season June to August tapping is greatly affected by heavy down pour although DRC is above 30% in that period. It is practically observed that, more than 50% of total production is achieved within the period of three months October to December. This uneven distribution of crop seriously affects management of work force and in latex processing especially accommodation of latex and smoked drying of sheets. Moreover, scarcity of wood fuel for smoke drying is also an acute problem.
By adopting simple techniques the above problems can easily be solved and the production cost can be reduced significantly. Hot air drying by natural gas, biogas or coal followed by 8 to 10 hours of smoking in double chambers will reduce the smoking cost at 15%. Efficient temperature maintenance, proper heat insulation and occasional turning of sheets can reduce the drying period and will increase the quality of the sheets. Marketing of hot air drying sheets should also be encouraged.
Although it is advised by some experts to switch over to other latex processing methods e.g. technically specified rubber (TSR) or block rubber and latex concentrates by centrifuging. It should be remembered that, initial big investment, processing capacity and use of electricity do not favor for establishment and running these factories. It is also not economically viable here at the present situation. The major rubber producing countries like Thailand (total NR production 2.59 million tons in 2002) and India (total NR production 649,435 tons in 2002-03) produced TSR 17 and 11.53% respectively, only. The production share of latex concentrates is also about 10%. Moreover, uneven flow of latex in different seasons does not assure economic running of TSR and latex concentrates plants. However, introduction of advance technologies is always preferred; after careful feasibility study that can only be implemented.
The world production of NR in 2002 was 7.01 million tons against the demand of 7.06 million tons. Present demand is 2.6% higher than last year and it will increase by 19.2% by 2010 (Peyman, 2003); therefore, it is predicted that the price will increase significantly in the world market. In this situation, the government should adopt a policy on import and on the use of off-grade rubber, at the same time production of good quality rubber (Prime grades: RSS 1, RSS 2 and RSS 3 should be more than 80%) in the country, must be ensured. The poor quality rubber is generally produced due to the lack of cleanliness in latex collection, handling and coagulation, inadequate addition of chemicals and improper drying, which is sold in ungraded. Rubber based industries; especially automobile-tyre industry should be installed.
Marketing of field coagulum (FC) or cup lump is getting importance for increased uses in the footwear industries. Trading of both FC and smoked dried rubber should be made through registered agencies to prevent illicit channeling of rubber from the gardens.
Rubber planted in moribund tea where top soil was degraded due to indiscriminate use of chemical fertilizers and pesticides, poor maintenance and poor shade and hard rock pan immediate below the surface, shows significant improvement of soil status and health reflected by the luxuriant growth of old moribund tea, after 7th years of rubber plantation. It is interesting to note that, the root network is so nicely spreaded in the topsoil up to a depth 60 to 70 cm. Soil micro-flora and earthworm activities improved significantly. Study is in progress for final recommendation on this subject.
Future of rubber
A good day is waiting for rubber crop within a very near future. It is well-established fact that natural rubber is superior to synthetic rubber in all respects. In consideration to environment, health and safety, bio-degradation and waste disposal factors it is also more acceptable. The tyre industry is the largest consumer of natural rubber and its demand is increasing with the increase of wheeler vehicles. The demand of natural rubber is increasing at the rate of 3% annually (20 years average), and the gap between supply and demand will be widen more than 7% by 2005 and 19.2% by 2010 (Peyman, 2003). Moreover, The three major rubber-producing countries, Malaysia, Thailand and Indonesia are encouraging to replanting rubber areas with oil palm as the current low price of rubber in the world market. Effectively it would take 10 to 15 years of consistent replanting and new planting to enable supply to catch up with demand. Hence, it is predicted that rubber could see a decade of higher prices, which is estimated at least double of the present market price.
For sustained growth of a plantation industry the positive margin between the cost of production and the sale price of the products is mandatory. Otherwise the effect will be negative. It will also affect the national economy as the initial investment, maintenance before and after maturity and other cost in management of a garden e.g. in employment, disaster recovery, productivity etc. will be a poor show in such a loosing concern. Although price of rubber was very low in the international market, which influenced the domestic market price earlier but now the problem no more, exists; still there must be some sort of mechanism or regulation to control the domestic market price to protect the plantation industry. As a plantation crop, there is no permanent or continuous crisis, but thinking all other aspects: like timber, environment, soil and improvement etc. domestic price control by the government is essential to save the plantation industry and to fetch the good price of rubber in the coming days by improving the yield and quality, meeting the country demand and exporting quality rubber.
Cultural practices should be followed very carefully, taking the references from the background study of similar habitats and environment for introducing a plantation crop. However, there will remain some problems always but these can easily be solved. As a potential important multipurpose plantation crop, there must have some sort of regulations under which industrial development, land utilization and allotment for plantation, management, employment, wages and benefits, health and safety, discipline, product standardization, commodity market, import and export price control, dealers’ licensing, research and development, technical training, statistics and publication etc. should immediately be programmed and materialized. ‘Follow up’ measures i.e. statistical evaluation, technology upgrading and future plan for development, should be kept active.
I would like to acknowledge Mr. Diderul Anwar, Chairman, Bangladesh Forest Industries Development Corporation for taking such a constructive decision by arranging this Seminar at an appropriate time. I would also express my sincere thanks to the Board of Directors and The managements and the staffs for the arrangement of the Seminar. I would also like to thank the other rubber growing and consumer industrial organizations that actively participated the seminar by helping many ways. Finally, I want to thank all the participants for their attention, cooperation and patience hearing.
Latest posts by Dr. Mohammed Ataur Rahman (see all)
- Ecosystem Management is the Key to Reduce Climate Impacts and Food Security - December 23, 2020
- Ecosystem Management is the Key to Reduce Climate Impacts and Food Security - December 23, 2020
- Climatic Adaptation and Sustainability of Rice in Bangladesh - September 5, 2020