More About Jatropha

The plant Jatropha curcas (L) is a multipurpose, drought resistant, large shrub or small tree belong to family Euphorbiaceae. Although it is a native of tropical America, it is widely cultivated in Africa and Asia. In English it is commonly known as purging nut and physic nut and in Tamil it is called as Kadalaamanakku or Kattamanakku.

The following are the salient features of Jatropha Curcas

ADAPTABILITY FEATURES
Perennial shrub and gives economic yield up to 25 years.
Hardy plant, rapid growth, drought resistant and survives well in arid and semi arid tropics.
Grows well in all types of soil and even in poor, marginal and degraded wastelands.
Easily propagated by seeds or stem cuttings.
Not browsed by cattle, no major pest & diseases and require low management.

ECONOMIC FEATURES
Has potential to yield seeds up to 5 tons / acre / year and contains 30–35% oil.
Raw Curcas oil is an ideal bio-fuel, could be mixed with diesel up to 20% and esterified oil is 100% diesel substitute. Cost-effective, renewable and environmentally safe bio fuel.
Besides fuel purpose, oil is also used in Soap and Paint industries.
Seeds and plant parts are also used for medicinal purposes and Dyes.
Curcas Oilcake contains high nutritive value and used as very good manure.
Jatropha oil & Oilcake have Insecticidal and molluscicidal Properties.

JATROPHA CURCAS – CULTIVATION PRACTICES

Climate
Jatropha curcas grows well in humid to semi-arid or arid tropical and sub tropical environments. Survives well with an average annual rainfall between 200 mm to 2000 mm and has ability to withstand extreme drought and light frost condition.

Soil
Jatropha curcas grows well in any type of soil whether gravelly, sandy, clayey or saline and thrives even on the degraded least fertile soils, stony soils and rock crevices.

Propagation
Jatropha curcas is a fast growing plant and can easily be propagated using either Seeds or stem cuttings. Stem cuttings should be taken only in one year old plants, already lignified and about 60 to 120cm long.

Planting
Direct Seeding:
The best time for direct seeding is the beginning of the rainy season. 2-3 Seeds are sown in the soil at a depth of 2-3 cm in each pit. Thin to one plant per pit.
Direct Planting:
Cuttings taken from one-year-old plants with the length of 60 –120 cm should be placed about 20 cm in to the soil. The best planting time is 1-2 months before seasonal rain.

Transplanting of Precultivated plants
Seedlings are raised in a small 200 gauge plastic bag (size 8” x 5”) by using either selected seeds or stem cuttings. The bags are filled with soil and organic manure and Bio fertilizers viz., Azotobacter and Phosphobacteria @ 1 gm each and VAM 5 gm , Bio control agents viz., Trichodermma Virdi and Pseudomonas @ 1 gm each should be added in the pot mixture. One seed is planted in each bag. Seed starts germinating after about 7-10days, after 3 months; at the beginning of the rainy season 30-40 cm high plants can be planted.

Inter cultivation
The field should be kept free from weeds in the initial periods until the crop crosses the grand growth period. Light harrowing between rows and plants are beneficial.

Pruning
The plant should be cut back with a sharp cutter at a height of about 30-45 cm from ground level, after a year of planting.
Allow the plants to grow and put on side branches up to next year.
In the second year, each side branches should be pruned by cutting 2/3rd top portion and retaining 1/3rd of branch on the plant. This will induce bush formation in an umbrella pattern rather than inducing medium tree like vertical woody growth.

Pest and Diseases
Generally Jatropha species are known to be infected with leaf spots, powdery mildew, leaf curl diseases and common pests such as leaf miner, leaf Webber and beetles. However None of these cause considerable yield losses.

Harvest
Ripe Jatropha fruits are yellow. The fruit dries and become hard and black. The dry fruit remain on branches. Harvest the fruit with a long stick with a circular comb with a cotton bag at one end. With this tool fruits can be picked from the trees, the picked fruit falls in to the bag and do not have to be found in the ground. Without this tool, fruits are hit by stick and they have to be collected on the ground.

Post Harvest & Processing
Drying: Before dehulling, the harvested fruits are to be dried in full sunshine by spreading the fruits over the plastic sheet or tarpaulin for a period of 2-3 days.
Decapsulation: The outer shell of the dried fruits are easily removed by mechanical/ hand sheller or manually by placing the capsules over a plat form and rub with wooden board, while pressing it down, the fruit hulls split and the seed comes out. Winnowing or sieving can separate fruit hulls and seed.