1. Is it true that Jatropha can grow in any conditions with very little crop care?
Jatropha is a hardy crop and can grow in harsher conditions as compared to other energy crops. However if the conditions are very harsh, the seed yield may not be economical. Also Jatropha plants tend to die or have stunted growth under certain conditions like snow, water logging, etc. Growing Jatropha on unused marginal lands with optimal crop care has the potential to give economic yields.
2. What type of soil is suitable for Jatropha cultivation?
In general Jatropha can grow on all soils except low lying lands known to have water logging problem, soils with more salts (saline soils) and acidic soil (pH <4.5). Jatropha can perform better in deep sandy loam soils with optimum pH of 6 to 8. Deep soils are preferred so as to enable the root system to grow deeper for water. Good agronomic practices can help address some soil problems.
3. What is the minimum rainfall for Jatropha cultivation?
Annual rainfall more than 800 mm is suitable for Jatropha cultivation; further it is also important that the rainfall is distributed for 4 to 6 months during the year.
4. What are the potential uses of Jatropha de-oiled cake?
Jatropha de-oiled cake can be directly used as manure in agricultural fields since it contains nutrients (N,P,K) which are at par with poultry manure. It is also a good feedstock for biogas production because of its composition. There are also technologies available for detoxifying the seed cake for animal feed. Jatropha seed cake along with the fruit shells can also be used for making briquettes, which are a good source of fuel.
5. Does Jatropha have a long gestation period?
Jatropha plants from natural habitats have 2 to 3 years of gestation period. However, there is scope for reducing it to 1 year through using improved varieties, adopting proper propagation technology and implementing proper agronomic practices before and after planting. Gestation period also depends on the region where the plant is growing. In regions with moderate climate and well distributed rainfall, it is found to flower and fruit early, thereby with a short gestation period.
6. What is the ideal planting density to be followed in commercial plantations?
The ideal planting density in commercial plantations is a function of various key factors like climate, soil fertility status, type of planting material used, intercropping requirements, etc. Very often, 2500 plants are planted for every ha of land. During the first two years, intercrops can be cultivated to utilize the space between the plants and in-situ resources.
7. Is Jatropha resistant to pests and diseases?
Jatropha has some level of tolerance to few pests and diseases in some regions but not resistant to all pests and diseases. For large scale plantations, management of potential pests and diseases are important factors until biotic stress resistant varieties are made available in the market.
8. Why does a Jatropha plant looks like a skeleton in certain conditions?
Jatropha generally undergo dormancy during unfavorable conditions like prolonged low temperature or drought. Under such conditions, the plants shed leaves completely and appear thin.
9. What is the best type of planting material for commercial plantation?
Seedlings/saplings with good yielding potential, tolerance to stresses and good rooting are the best planting material. They will have better establishment and good productivity. However, the release of such improved Jatropha varieties commercially has yet to happen. For the time being, making available the best local genetic resources and good agronomic practices is the best option of achieving a good plantation.
10. What is the best way of propagating Jatropha? Is it through seeds, cuttings, nursery raised saplings or any other method?
There are three approaches to Jatropha propagation, each with advantages and disadvantages:
• Seeds: Healthy seeds are selected and sowed in seed bed or polyethylene bags with soil. Healthy seedlings from two to four month old can be transplanted to field. Due to natural segregation, seed derived populations are generally not uniform in growth and productivity. Seeds also tend to lose viability of germination fast under normal conditions.
• Vegetative Cuttings: Jatropha can also be propagated through vegetative cuttings from adult plants. Branches are cut into pieces of various lengths, treated with fungicide and allow for rooting in humid greenhouse or polybags. It is not very efficient in propagation and weak roots are reported for plants from stem cuttings.
• Tissue Culture: Mass multiplication of best performing trees is possible through tissue culture; which enables producing millions of propagates in a short time. Plants from tissue culture possess advantages like uniformity in yield and oil content and homogeneity in other agronomic traits. There has been a lot of research work on the development of optimal protocol for commercial multiplication of elite Jatropha hybrids. JOil (S) Pte Ltd is a leading player in this area.
11. What is the minimum duration of storage for Jatropha seeds for good germination, oil content and physical purity?
Below 6 months under room temperature and low humidity. To maintain viability for longer period, steps should be taken to store the seeds under relatively lower humidity and temperature.
12. Will the economics of Jatropha be improved if large plantations are drip irrigated?
Drip irrigation is a viable option in low rainfall areas. However, the economics of drip irrigation will only work with high yielding, good quality planting material over a longer duration.
13. What are the thoughts behind eligibility of Jatropha plantations for carbon credits? What are the requirements in the plantation to achieve it?
Jatropha may be eligible for carbon credits as it can grow in marginal land. It captures carbon during its growth and importantly, using Jatropha oil or biodiesel offsets carbon dioxide emissions by conventional fossil fuels. Jatropha fruits shells, seed cake, pruned branches can be used for making briquettes and biogas, which are also good sources of carbon credit. To maximize carbon credit, fossil fuel derived fertilizers and chemicals should be used as less as possible since their production emits greenhouse gases. Several parties are working towards getting carbon credits.
14. What can be a sustainable model for Jatropha plantation and minimum size of plantation to be economically viable?
Sustainability of Jatropha plantation is determined by revenue after cost. Revenue depends mostly on seed/oil productivity and price. Productivity in turn depends on quality of plantation materials, climate conditions, agronomic practices and inputs. Acreage is a less important factor although it is generally believed that large scale plantation has economy of scale, meaning more efficient operation and less cost.
15. What is the cost of production of a tonne of Jatropha seeds? To be more precise, what is the average yield of Jatropha per acre?
Jatropha is not domesticated yet and there is a wide range of seed productivity (from 0.1 to 12 tons per ha per year) reported, hence cost of production is still uncertain. There are global efforts to breed for more productive Jatropha varieties and make the elite plantation materials available. With elite plantation materials with more uniform and predictable performance, cost of production can be reliably calculated.
16. Is contract farming a viable option in Jatropha cultivation?
Contract farming is one model of Jatropha cultivation. It will be more viable if alternate income is available to the contract farmer before harvesting of Jatropha seeds. Intercropping is promoted to serve the dual purposes of providing income to farmers and eliminating weed competition before establishment of Jatropha plants.
17. What will be the productive life span of a commercial Jatropha plantation?
The productive life span of Jatropha is estimated to be 20 to 30 years. However, continuous production will need maintenance like pruning and fertilization.
18. Is nursery an important aspect in Jatropha plantation planning? Or can it be outsourced? Which is economical?
Seed germination in nursery followed by transplanting into field is recommended because of better quality and more uniform seedlings. It should be noted, however, using seeds from unknown source or from hybrid plants may lead to very variable performance. When highly productive and uniform planting materials are available from a reputable source, it is better to opt for it as good plants will generate better income year after year.
19. What is the cost per sapling/seedling of elite Jatropha?
This depends on the type of saplings/seedlings supplied. If the sapling/seedling is raised from seeds, it will be cheaper compared to the ones from stem cutting or plant tissue culture. Since plantation material is just a small part of production cost, it is better to go for the best available saplings/seedlings.
20. What are the major issues concerning Jatropha ailing the world today?
The major issues are lack of good quality planting material and good agronomic practices. These are slowly getting resolved due to the efforts put forth by many devoted public and private research organizations around the world.
21. What are the reasons for low germination and viability of procured Jatropha seeds?
Most likely, it is related to the practice of collecting Jatropha fruits after they are completely dry or have fallen down from the tree. Drying seeds directly under the sun for a long period or keeping seeds at high temperature will reduce germination ratio. It is best to buy strong and healthy seedlings from reliable sources.
22. What is the appropriate time and ideal fruit color to harvest Jatropha fruits?
To get good quality seeds, it is always better to pick fruits when they are yellowish black in color and dry fruits under shade with good ventilation. Seeds should be stored in the dark under low temperature and moisture.
23. What are the future prospects of Jatropha?
With increasing fossil fuel prices and also the call to reduce emission of greenhouse gases, the future prospect of Jatropha looks very bright. It has good potential to be a sustainable and environmental friendly energy plant. High quality plantation materials together with good agronomic practices will make Jatropha commercially viable. Eventually, confidence of the people in Jatropha will rise to the levels anticipated in the early years.