Natural rubber, also called India rubber or caoutchouc, as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds plus water. Malaysia is a leading producer of rubber. Forms of polyisoprene that are used as natural rubbers are classified as elastomers. Natural rubber is used by many manufacturing companies for the production of rubber products. It is used for many purposes which may include erasers to tyres, tubes & industrial products. Currently, rubber is harvested mainly in the form of the latex from certain trees.

The latex is a sticky, milky colloid drawn off by making incisions into the bark and collecting the fluid in vessels in a process called “tapping”. The latex then is refined into rubber ready for commercial processing. Natural rubber is used extensively in many applications and products, either alone or in combination with other materials. In most of its useful forms, it has a large stretch ratio and highresilience, and is extremely waterproof.

Climatic condition for Rubber Farming

The rubber plantation requires heavy and well distributed rainfall of 200 cm to 300 cm having humidity about 75%. The best growing temperatures for rubber plant is from 20°C to 35°C. Freezing temperatures will halt the temperatures for rubber plant is from 20°C to 35°C. Freezing temperatures will halt the growth of rubber plants and strong wind areas are not suitable for rubber farming. This plantation requires at least 5 to 6 hours of sunlight.

Soil for Rubber Farming

Rubber Plants require highly deep weathered soils which consist of laterite and lateritic soils. They grow best in well drained porous soils with moderate acidic in nature. However, rubber plant also thrives in red alluvial soils, if there is a good organic matter in the soil. The soil pH of 5.0 to 6.0 is best for rubber cultivation. For good aeration and root growth, water table should be below at least 1 meter depth in the soil

Preparation of Land for Rubber Farming

The main field should be cleared of wild growth and pits with dimensions of 120 cm x 45 cm x 60 cm should be dug along the contour @ suitable intervals. Usually it takes 200 to 250 pits per 1 hectare land. The rubber planting depends on the type of land, if it is levelled one, square planting is suitable where as slope lands are best for rectangular plantation. In hilly areas, row planting is recommended across the slope along the contour lines. Make sure to form 2m width of terrace. The rubber plant density for 1 hectare land is about 450. Pits of 75 cm x 75 cm x 75 cm should be dug and filled with top soil having 10 kg organic matter and 150 grams of rock phosphate. Make sure to plant in the middle of the pit providing mulch and shade.

Planting Season

Plantation In rubber cultivation, June to July is the best season for its plantation

Propagation in Rubber Plantation

Normally in rubber cultivation, propagation is done through green budding, crown budding and brown budding

Planting Method and Spacing in Rubber Plantation

Manures and Fertilizers in Rubber Plantation

Normally rubber plants respond very well to organic matter and fertilizers. 10 to 12 kg of well rotten organic manure and 225 grams of rock phosphate should be applied to each plant pit while preparing the pit as basal application. This dosage is recommended up to 4th year of planting. In case of soils having magnesium deficiency a fertilizer mixture of 10:10:4:1.5 of N: P2O5:K2O: MgO @ 100, 400, 500 & 400 kg per hectare should be applied during the 1st, 2nd, 3rd & 4th year of rubber planting.

In case of magnesium rich soils, a fertilizer mixture of 12:12:6 of N: P2O5:K2O @ 85, 340, 430 and 340 kg per hectare should be applied during 1st, 2nd, 3rd & 4th year of rubber planting. From 5th years onwards, NPK mixture of 10:10:10 @ 300kg per hectare or 900 grams per tree is recommended. In the case of polybag planting, double dose of fertilizers should be applied during the first year.

Intercultural Operations and Weed control in Rubber Plantation

1) Intercropping In rubber plantation is intercropping will generate good revenue during first two years of cultivation. The suitable intercrops in rubber plantation are like ginger turmeric, tuber crops, vegetables, pineapple, banana and medicinal or herbal plants 2)Cover cropping

2)Cover cropping is helpful in sloppy regions to prevent soil erosion. This also helps in enhancing the soil fertility and controls the weed growth along with soil temperature. Intercropping like Leguminous crops will help in nitrogen fixation in the soil. Calopagonium muconoides, centrosema pubescens, pueraria phaseoloides and desmodium evalifolium are common cover crops in rubber plantation. Weed Control: In rubber plantation, weeding is usually carried out manually or chemicallyor through a combination of both. The main weeds commonly found in rubber plantationare Axonopus, Paspalum, Digitaria, Mikania, Sida, Pennisetum, Eupatorium, Chromolaena, Borreria, Lantana, Mimosa, Clerodendron. As a pre-emergence application, chemical herbicides like Alachor, Diuron & Simazina should be applied to control the weeds. Herbicides like Paraquat and Glyphosate can be applied in the post emergent stage. Herbicides like Paraquat and Glyphosate can be applied in the post emergent stage

Plant growth in Rubber Plantation

Plant growth: Usually, tree girth plays major role in tapping. The tree girth increases every year. The tree girth grows about 5 cm, 10 cm and 15 cm in 1st, 2 and 3 rd year of plantation respectively. The girth rate would be faster after 3rd year and reaches about 30 cm at the end of 4th year and thereafter, can expect up to 37 to 40 cm of girth. Seventh year is the end of gestation period and trunk girth can be expected about 50 cm & becomes ready for tapping. In the rubber cultivation, latex production increases every year up to 11th year. In the 1st year of tapping, about 65 to 70% of trees become matured for operation.

Tapping and processing

Tapping operation of trees begin when the rubber tree attains a girth of 50 cm at height about 125 to 130 cm. usually, the number of tapping days in a year is about 200 to 325. Tapping wages are major component of the cost of production and which greatly influence the returns. Adopting low frequency tapping systems are recommended. Tapping at the rate of once in 3, 4 and 6 days are most desirable to reduce the cost. To increase the yield of latex, Ethrel is recommended at 5% a.i. concentration with a brush below the tapping cut @ a width of 5 cm after light scraping of the outer bark. Preferably, the first application of Ethrel should be done after a drought period

Yield of Rubber

In rubber plantation yield depends on the method of propagation. In any method, usually yield increases year by year. The yield reaches peak after 14 to 15 years of planting. An annual average yield of rubber is about 375 to 400 kg/hectare from seedlings trees. In budded plants, an average yield of 800 – 1000 kg per hectare can be obtained.