BRIEF INFORMATION ON JATROPHA CURCAS: (VanaErand or RatanJyot)
Common Names:
English: Physic nut, Purging nut
Kamba: Kyaiki kyakyeni, Kya muunyi
Luo: Jok
What is this plant?
The name Jatropha comes from two Greek words meaning physician and food. It is one of more than 150 types of Jatropha species, mainly occurring in tropical America and Africa. This species was introduced in Africa centuries ago and is now naturalized in drier areas in many countries. A decorative plant frequently planted as a live fence around homesteads or used as a boundary or a grave marker.
It has adapted itself in bushland and along rivers in Western, Central and Coastal parts of Kenya.Promising trees with potential to meet various needs have been evaluated and Jatropha curcas has been favoured due to the following reasons: high oil content; ability to adapt itself even in low potential and marginalized areas which receive very low amounts of average annual rainfall; easy to establish and grows relatively quickly and is hardy; ease in seed collection activities; not browsed by animals; rich in nitrogen and other nutrients; it takes short periods to seed production; value as a medicinal plant, honey production and tannin; removes carbon from the atmosphere; can be propagated from seeds as well as cuttings; undemanding in soil type and does not require tillage. All attempts to increase its production and productivity therefore should be encouraged.
Introduction:
Justifying climate change by reducing emission of green house gases (GHG's), meeting rural energy needs, protecting the environment and generating gainful employment, are some of the biggest challenges facing most economies in the world today. With the shortage of Petro-diesel (normal fossil diesel) and soaring (increasing) prices, the world is going the Bio-Diesel way and Kenya is no exception. Bio-diesel is basically a Tree Borne Oil (TBO) and the best source of producing bio-diesel is Jatropha curcas, a plant that grows well mainly in tropical climate.
Supply of Jatropha seeds for the commercial production of Bio-diesel and for cultivation purposes are available and mass scale cultivation is going on in Kenya. Nursery propagation of Jatropha needs specialized agro techniques to get plants to yield requisite oil yields and the plant needs specialized training (Pruning) to make it adequately seed bearing just like tea plant and should be done under professional guidance. Seed yield varies from 6,000kgs/ha on the 3rd /4th year depending on agro techniques.
Bio-diesel is a better fuel than Petro-diesel and meets most of the chemical and physical standards of Petro-diesel. Being plant based it does not emit green house gases like sulphur oxides, Carbon dioxide and other gases on burning and is non-polluting, bio degradable and environmentally safe. Biodiesel can be used in any proportion to dope (add to) the Petro-diesel and it can very safely be used as 100% replacement of Petro-diesel in all kinds of diesel engines without any modification of the currently available diesel engines.
How does it look like?
Jatropha curcas is a small tree or shrub with smooth grey bark, which exudes whitish colored, watery, latex when cut. Normally, it grows between 3 and 5 metres in height but can attain a height of 8 or 10 metres under favourable conditions. It has large green leaves, alternate to sub-opposite, three to five lobed. Flowers are in form of inflorescence and are formed in the leaf axil. Female flowers are usually slightly larger than male flowers and occur in hot season. Flowering occurs during the wet season and two flowering peaks are often seen. In permanently humid areas flowering occurs through out the year. The seeds mature about three months after flowering. Normally Jatropha can naturally flower only once a year, but with modern techniques it can be forced to flower twice or thrice a year.
Fruits are produced during cold weather when the shrub is leafless, or it may produce several crops during the year if soil moisture is good and temperature sufficiently high. A young Jatropha Plant. Each inflorescence (bunch of flowers) yields a bunch of approximately 10 or more fruits. There are usually three seeds in each fruit. These seeds become mature when the capsule (fruit) changes from green to yellow after two to four months from fertilization. The seeds are blackish, thin shelled and resemble small castor seeds.
Where does it grow? Jatropha grows almost anywhere - even on gravelly, sandy and saline soils. It can thrive on the poorest stony soils. It can grow even in the crevices of rocks. It can grow in soft, rocky, sloping soils along a mountain as well as medium fertile lands. It can also be grown along canals, water streams, and boundaries of crop fields, along the roads and along railway lines. Highly fertile black cotton soils with high water holding capacity as well as alkaline soils are not good for Jatropha. Climatically, Jatropha is found in the tropics and subtropics and likes heat although it does well even in lower temperatures and can withstand a light frost. It can stand long periods of drought by shedding leaves to reduce transpiration loss. The plant can grow in areas where mean annual rainfall is 300 - 1000mm. It grows well in altitudes between 0-500m, mean annual temperature of between 20-280C. Jatropha grows on well-drained soils with good aeration and is well adapted to marginal soils with low nutrient content. On heavy soils root formation is reduced. Jatropha is a highly adaptable species but its strength as a crop comes from its ability to grow on very poor and dry sites.
How do you grow it?
From seeds: The seeds are sown in a seedbed either through broadcasting or in rows. The seeds are then buried at a depth equivalent to two times the thickness of the seed. Seeds should be placed in such a way that they do not touch each other to avoid disease and fungal increased growth or production. The first shoots are expected after four to seven days of sowing. Seedlings are usually transplanted into either 6 x 9cm or bigger sized potting polythene papers (bags) when the third leaf starts to develop or after a period of two weeks. Transplanting to the field is usually determined by the on-set of rainy season.
From Cuttings: 0.5m to 1.0m long branches can be used for plantation establishment. These are planted at the onset of long rains. Plants grown from such branches start producing yields after a period of eight (8) months
Nursery Management:
Good nursery work is the basis of successful afforestation activities. Good management of the nursery will result in seedling production at the end of the first year itself. Nurseries will supply seedlings to the farmers in their villages. Therefore in order to guarantee good quality seedlings and survival in the field after planting, good nursery practices should be followed. To raise sufficient nursery stock, information on choice of site needs to be considered carefully. Ensure there is a constant water supply, procure proper soil and manure or fertilizer and the nursery must be protected against domestic or wild animals and wind.
The slope must be gentle or flat and sunlight must be optimized. Size of the plots, accessibility by vehicles and centrality to serve a wider population are also factors that need to be carefully assessed.
Planting in large numbers (Plantation):
Pits of standard size are dug initially, based on the slope of the land, availability of water and quality of soil. Pits of 60cm x 60cm and 60cm deep are dug in square formation. The distance between two pits is 2 metres or more depending on the condition of the soil. In the initial phase of growth, roots grow very rapidly and try to penetrate in soil to suck nutrients from the soil. For this the pits should be filled with good, fertile soil. Initial growth is very important and hence for poor soils, nutrients should be provided from time to time in initial periods. All the weeds should be removed around the plant. Initially for 3 to 4 months, land should be tilled 2 or 3 times or after every 20 days.
The rising top of the plant should be cut once the tree is 1m or less tall. This will lead to branching of the tree. The more branches a plant has, the higher the production of fruits and therefore seeds. Every year, branches grow near the base, and these should be removed and replanted elsewhere. It is very important to cut the tree in time and keep it in proper shape.
How to Pack and store your seeds:
Seeds are sorted as good, medium and poor quality. Good seeds are used for plantation while others are used for extracting oil. Seeds should not be stored in damp and dark place as low light intensity encourages proliferation of fungus which compromises the quality of the seed and eventually the oil. It should be stored in sealed boxes or plastic sacks to limit gaseous exchange while ensuring prolonged life of the seed.
What are the Uses of Jatropha curcas?
Jatropha Oil is also used as an alternative to diesel oil and is also being used extensively for making soap in some countries. Also the oil is used as an illuminant in lamps as it burns without emitting smoke and other hazardous gases. It is also used as fuel in place of or along kerosene in stoves. In medicine, the ether extract shows antibiotic properties, the latex of Jatropha contains an alkaloid known as Jatrophine which is believed to have anti-cancerous properties. It is also used as an external application for skin diseases and rheumatism and for sores for domestic livestock. In addition, the tender twigs of the plant are used for cleaning teeth while the juice of the leaves is used as an external application for piles. Finally the roots are used as an antidote for snake bites. The bark of Jatropha yields a dark blue dye which is used for colouring cloth, fishing nets and lines. Jatropha curcas seed cake is rich in nitrogen, phosphorus and potassium and can be used as organic manure. Jatropha leaves are used as food for the tusser silkworm. The seeds are considered anthelmintic in Brazil, and the leaves are used for fumigating houses against bed bugs. READ MORE
