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RUBBER PRODUCTION IN NIGERIA Extension Bulletin No.213 Forestry Series No. 14 Published by National Agricultural Extension and Research Liaison Services, Ahmadu Bello University, P. M. B. 1067, Zaria. 2000 Acknowledgement The author of this bulletin acknowledge the management of NAERLS, ABU; and the Rubber Research Institute of Nigeria (RRIN) who provided the logistic support for the production of this Bulletin. Our appreciation goes to Dr. Johnson Onyibe and Crop & Forestry staff for their encouragement which led to the final production. Finally, I appreciate the NAERLS Publication Review Committee for editing the manuscript. Uyovisere Edna 2000 Table of contents Acknowledgement........................................................................ 2 Table of contents........................................................................... 3 Introduction................................................................... 4 Agronomic Practices................................................................... 4 Root stock nursery Establishment............................................. 6 Field Planting................................................................................ 11 Conclusion................................................................................... 19 BIBLIOGRAPHY......................................................................... 20 2 Introduction Natural rubber, Para rubber, Hevea Brasiliensis, is a commercial tree economically grown in plantations. Para rubber plant is useful for the latex that bleeds from the stem in the event of wounding. The product of the coagulated latex is rubber. Rubber is used in the manufacture a number of industrial products which range from tires, balls, containers, shoes to bands and a lot of other items. Rubber is important in the socio-economic life of many tropical developing nations, such as Nigeria and Brazil. Before the 60s, before the era of the oil boom, rubber was one of the agricultural commodities that were the main stay of Nigerian economy. The cultivation of rubber provided bulk employment for the people of the then Mid-West now known as the Edo and Delta states. However, rubber is not native to Nigeria. As the name suggests, it is an introduction from Brazil. Agronomic Practices Soil/weather requirement: Rubber requires a well-drained, sandy loam, well-aerated permeable subsoil in which its root system can proliferate. Rubber cannot stand a waterlogged soil. A land drained to at least 1.2m is adequate for rubber. Annual rainfall of at least 1700mm well distributed throughout the year with a short dry spell is ideal for the growth of the plant. Soil rich in nitrogen are preferred although phosphorous and potassium must also be available as well as trace elements. Temperatures between 240C and 350C or more are needed for proper growth of rubber. Land Preparation: Land preparation for the cultivation of rubber can be carried out either manually or with the use of mechanical power. The choice of method depends on the available resources and the cost of equipment and labour. 3 Mechanical land preparation involves the use of heavy machinery to remove and pack heavy tress. The advantage in the use of mechanical power is in the short period required for clearing large expanse of land and neat packing of felled materials. However, with the mechanical land clearing there is the possibility of compacting the fragile soils and removal of topsoil, which can lead to soil erosion. In order to avoid these undesirable side effects in the use of mechanical power, experienced hands should be engaged to operate the equipment while it is also important to seek advise from knowledgeable extension agents. Planting materials. Rubber tree can be grown from ‘ordinary seeds’ (referred to as “illegitimate seeds), from the so-called clonal seeds or budded seedlings of either the ordinary seeds or clonal rubber. Planting through unbudded seedlings obtained from ‘ordinary seeds’ are not recommended. Most rubber plantations in Nigeria are planted with varieties of rubber referred to as clonal rubber. A clone is a group of plants in which all the individuals are obtained by vegetative propagation from a single mother tree. Thus there are certain welldefined characters that are constant with a clone. The budded rubber stump is obtained by grafting a scion of a highyielding variety onto a seedling rootstock. The production of budded stumps requires reasonable capital outlay coupled with special techniques. This is why only commercially oriented producers go into rubber stump production. Most growers rather purchase their budded stumps from recognised sources. Recognised sources include the Rubber Research Institute Iyanomo Benin, the Agric. Development Programme and other recognised producers. 4 Recommended Clones A GTI Java Clone has the best all-round characteristics and can be planted with safety anywhere except where moisture levels are low. PRION Java is a slow starter in terms of yield but has other good characteristics. It has an excellent shading facility thus recurrent maintenancecost is reduced. This clone is susceptible to Phytophthora in high rainfall areas. RRIM 600 Malaysia is a top yielding clone but is susceptible to both Phytophthora and Pink disease and should not be planted in areas of high wind velocity.PB5/51 Malaysia. RRIM 600 Malaysia yields less than the clone listed above is somewhat susceptible to Oidium. It is the most wind resistant of all clones developed for large scale planting. However it has a tendency toward brown blast disease and the bark renewal is below average. Root stock nursery Establishment A rootstock nursery is one in which healthy seeds are raised to produce the seedling material onto which, the scions are budgrafted. The objective of a nursery is to be able to grow healthy young plants, which after budding are transplanted to the field. Nursery establishment requires careful planing and timing. Pre-nursery: Rubber seed fall occurs in Nigeria between August and September. Fresh seeds from early seed falls are best for optimum germination. Fresh seeds lose 50% of the moisture content within a few days. Therefore seeds should be planted in the germination bed within 48 hours of collection. Do not select light and shrunken seed. Seeds for germination can be prepared either from sand beds or box beds. The rate of germination in sand beds is much higher than in box beds. It is recommended that sand beds be used. 5 The soil of the bed should be turned over and raised to a height of 1525cm before being leveled. The width of the bed should not exceed 1.5m (5ft) with paths between the beds to permit easy movement around the beds. A layer of sand 6cm (2 inches) deep should be spread on the surface of the bed. The freshly collected seeds to be germinated are pressed by the flat side downward at such a depth that the upper surface is just visible. The seeds should be very close to each other so that the bed can contain as many seeds as possible. The beds, usually constructed in shaded areas, should be mulched with grasses and watered daily. As soon as the seed sprouts or the radicle emerges, the germinated seeds should be transferred into main nursery. Seeds that fail to germinate after 7 days should be discarded. For a hectare, 180,000 seeds are required in a rootstock pre-nursery, this allows for 50% germination. Main (field) Nursery Two methods can be used in the main nursery: 1. the conventional bed and 2. the polybag method Field Nursery: Site Selection: Select a location that is fully exposed to sunlight close to a readily available supply of water. A flat or near flatland with a loamy textured soil is ideal. It is important to avoid areas where flooding can occur and if possible the area should be close to the budded stumps (either on the beds or polybags are to be planted). Field Preparation: Cultivate the land by ploughing and harrowing to provide a good texture. Ploughing and harrowing should be done early enough before the heavy rains in July. If cultivation is done too late when the soil moisture is high, the puddled soil may result in excessive run-off leading to soil Erosion. 6 Field Nursery Layout: A basic double-row system – 30cm between plants: 60cm between every 2 row. nd On a conventional bed and at a spacing of 30cm x 30cm about 90,000 seedling can be raised per hectare. The beds should be free of weeds either through hoe weeding or the use of herbicides such as gramozone or ‘roundup’ used at least two weeks before transplanting. In the nursery lining can be done using a thin rope which is marked at the appropriate spacing of 30cm and laid along the proposed row. Seed planting should be carefully done because of the delicate nature of the germinated seed. The germinated seed is placed in the shallow hole with the flattened end. Thus is then covered with a small quantity of soil. 30cm 30cm 60cm 7 Thining: The first thinning is carried out after 3-4 months of growth. Stunted and any seriously disease infected seedlings are discarded. The second thinning is done between the 7 and 8 month and this should reduce the population to about 45000, which is about ¼ of the original seed Polybag Nursery Method: Planting materials in polybags provides optimum degree of selectivity and polybagged stumps achieve much greater uniformity in growth at field planting. Provided they are well taken care of, polybagged budded stumps, attain maturity at least a year In Nigeria, budding is done in the wet season, commencing from the late April and extends to mid-October. However the best periods to bud are: (i) Early May until mid-July (ii) Mid September until mid October (dormant budding) Budding during the heavy rains i.e. (mid-July to mid-September) is not advisable because of the disease anthracose is very severe in wet conditions and throughout the nursery thus reducing the budding success severely. In order to achieve the best results, the following should strictly be observed: 1. Do not bud in the rain when the materials are wet. Diseases are easily be transferred with wet materials. 2. Avoid budding during the dry season unless some form of irrigation or adequate watering is ensured. 3. Delay commencement of budding operations until the morning mists have subsided. This is to provide a dry surface on the budding materials. 4. Ensure that rootstocks attain a minimum diameter of 5cm and are vigorous. 5. Avoid budding to old or very large rootstock. The barks of old or large rootstock are inclined to split. th 8 th