Jatropha curcas is a perennial, oil-seed bearing shrub originating from Central America and which has been introduced to other tropical regions in Africa and Asia. Unlike palm or soy, which are key edible cooking oils, jatropha trees become poisonous within months of growth, meaning that the branches, leaves and seeds cannot be eaten by humans or animals. The net result of this is that Jatropha oil does not suffer from direct competition with food crops, as is the case with most other biofuels feed stocks. Another benefit of growing Jatropha is that it grows well in hot and arid regions and on marginal soils with low nutrient content, and that the trees have a ‘built-in’ capacity to combat desertification by restoring vegetative cover.
In addition, the plant is relatively drought resistant. When mature, Jatropha trees produce large quantities of seeds, which can be crushed to produce oil. This oil can be used directly as fuel in some older type diesel engines, mixed with conventional diesel up to 25% to use in most diesel engines or further processed by trans-esterification to produce biodiesel which can be used in every modern engine. Another advantage of cultivating Jatropha is its relative drought resistance. One of the reasons for this is that Jatropha trees have unique root architecture, comprising a thick central taproot and four laterals. With this central taproot a tree can extract minerals from deep inside the soil like a “minerals pump”, which promotes soil fertilization recovery and faster plant growth. Secondly, when the taproot is simultaneously able to withdraw water from deeper soil layers this contributes to the tree’s drought resistance and a further increase in overall plant growth and seed production. In addition, the four lateral roots as a distinct Jatropha plant feature provide additional structure to the surrounding soil, which gives a positive contribution to the soil water storage capacity and soil erosion control. Niqel is working on better species with higher overall yield levels. This will be achieved through systematic seed selection and supported by a scientific seed-breeding programme in cooperation with leading universities and research institutes.
After drying and processing, one metric tonne (mt) of Jatropha grain typically results in 250kg – 350 kg of oil, 350-400 kg of high energy hulls and the balance in a Jatropha kernel meal containing circa 65% protein.
Seedlings derived from superior planting materials are painstakingly nurtured for several months. Niqel adopts precision agriculture technologies to capture and derive information and data such as sizes of management blocks or plots, tree stands, locations of roads, and soil boundaries, among others to aid in estate management.
Breeding strategies are based on shaping the adaptability of the plant to suit the specific environment. Cultivars are developed to be capable of producing high quality oil, higher yields at early age and higher yields through greater quantities of fruit.
A remarkably deep rooting plant, down to 4 meters, it is a useful plant in soil remediation, bringing deep mineral fertility to the soil via leaf litter. Small tree with growth up to 5 metres which is able to remain productive for up to 50 years.
The plant produces bunches of 2-3 cm diameter fruits, which contain 3, black 1 cm long seeds or grains of approximately 0.8 grams each. The grains have thick black hulls protecting the grain kernels. The kernels are rich in oil and protein.