Jatropha Plantation Research Articles

The Effect of Curcin Protein and Jatropha Plantation on Soil Fungi

Jatropha curcas is widely planted as a highly drought-resistant biodiesel feedstock. Curcin protein is one of the Jatropha ribosomal inactivation proteins with broad-spectrum antifungal activity that may enter the soil ecosystem as a result of large-scale Jatropha cultivation and affect fungi and various enzymatic activities in the soil. In this research, the influence of curcin protein and Jatropha planting on soil fungi was investigated, and the levels of curcin in various tissues and organs of Jatropha were measured with an enzyme-linked immunosorbent assay. It was found that the content of curcin in seed kernels reaches 2 mg/g, which is much higher than that in other tissues. After the seeds have fallen into the soil, the level of curcin in the soil rises rapidly, reaching 59.22 µg/g soil and 67.49 µg/g soil in different soil samples, respectively. It then falls by more than 99% within six days. High-throughput sequencing technology was used to study the soils treated with different concentrations of curcin, and the results of the soil fungal alpha diversity index analysis showed that the fungal communities did not change significantly, but the abundance of each fungal community changed significantly. The degree of influence of different concentrations of curcin treatment on the abundance of the soil dominant fungal community were investigated for concentrations of 0.5 μg/g, 50 μg/g and 5 μg/g, and showed that concentrations of 0.5 μg/g and 50 μg/g are more likely to change fungal community structure in soil, and with the increasing extension of the treatment time, they may be detrimental to the conservation of soil ecosystems. Internal transcribed spacer (ITS) sequencing of soil fungi from Jatropha planted and unplanted areas in four regions with different climate types showed that Jatropha planting significantly altered the soil fungal communities in each region. There was a negative impact on soil fungal communities in tropical maritime monsoon and subtropical dry and hot monsoon climates, while a positive impact was observed in subtropical monsoon and tropical highland monsoon climates due to Jatropha cultivation. In conclusion, Jatropha plantations and curcin protein have an impact on soil fungi and thereby affect the ecological system of the soil.

QUALITATIVE STUDY OF CONTROLLING PEST OF JATROPHA CURCAS FOR LINEAR FUNCTIONAL RESPONSE

In today's world, Jatropha curcas plants are a renewable energy feedstock for producing biodiesel to overcome the limitations of natural fuel. The alternative fuel biodiesel can be produced from the Jatropha plant as its seeds contain oil which is one of the important resources for biodiesel. Despite being toxic to many insects and animals, the Jatropha curcas plant is not pest and disease-free. In view of this, our research article presents the formulation and analysis of a mathematical model that describes the Jatropha plantation along with a prediction to control its natural pests by biological pesticides. We assume linear functional response of predators for susceptible pests, and infected pests as infected pests are weaker than susceptible pests and easy to catch. The dynamics of the system around each of the ecologically feasible equilibria are studied. The reduction of disease eradication and coexistence of predator and pest are observed around the predator-free and disease-free equilibrium respectively.

Yield Potential Of Indonesian Jatropha New Variety (Jet-1 Agribun) Under Rainfed Condition

Jet-1 Agribun is one of the Indonesian Jatropha new varieties suitable for rainfed areas with a high yield of dry seed and oil content. The field trial was conducted at Asembagus Experimental Station in Situbondo, East Java from February to December 2019 and aimed to observe the potential of Jatropha Jet-1 Agribun under rainfed conditions. Observation on seed yield and growth components of Jatropha plantation was also made in two and three years old Jet-1 Agribun. Results of the observation showed that Jet-1 Agribun in the first year produced seed 471.8 kg/ha. A two-year-old plant produced a dry seed of 3,958.7 kg/ha. Three-year-old plants after pruning produced dry seed 910.95 kg/ha and 916.04 kg/ha at 1 m x 1 m and 2 m x 2 m, respectively, indicating that wider spacing is more allowable for cropping with food crops until the canopy closes. Development of Jatropha should be integrated with food crops or other crops through intercropping systems, by using the land around the plants until the canopy closes.

ECONOMIC FEASIBILITY FOR THE PRODUCTION OF JATROPHA ON A SMALL SCALE IRRIGATED BY TREATED WASTEWATER

Energy is a vital driving force for development; access to energy can alleviate poverty, improve living conditions and propel economic development. Biofuels as a fossil energy alternative has gained worldwide attention for many years. Drastic changes in the energy system are needed. However, the establishment of the required new energy technologies and associated infrastructure will in itself lead to GHG emissions. Other important aspect affecting Egypt’s agriculture income is water scarcity. Egypt will need to improve the way they manage their water resources and associated services. However, expansion of Jatropha plantation largely depends on profitability from such plantations on small- scale level. The study reveals that Jatropha is a potential renewable energy resource with advantage of grown on marginal lands and irrigated by treated of waste water. The main objective of the study is to assess the profitability of Jatropha through discounted indicators in order to enhancing the sustainable development in Egypt. This study has shown positive returns from Jatropha plantation during the period 2008- 2022. Although the net present value at discount ratio of 30% was LE 8.2 thousand, while the benefit/ cost ratio was 1.45.

Local food security impacts of biofuel crop production in southern Africa

Biofuels have been promoted as a renewable energy option in many countries, but have also faced extensive scrutiny over their sustainability. Food security is perhaps the most debated sustainability impact of biofuels, especially in regions such as Sub-Saharan Africa that experience high rates of malnutrition and have been a major destination for biofuel-related investments. This study assesses the local food security impacts of engagement in biofuel crop production using a consistent protocol between multiple crops and sites. We use standardized metrics of food security related to dietary diversity and perceptions of hunger, and focus on feedstock smallholders and plantation workers in four operational projects: a large-scale jatropha plantation (Mozambique), a smallholder-based jatropha project (Malawi) and two hybrid sugarcane projects (Malawi, Eswatini). Collectively these reflect the main feedstocks, modes of production and land use transitions related to biofuel projects in Sub-Sahara Africa. Inverse Probability Weighting analysis indicates that involvement in sugarcane production improved household food security for plantation workers and feedstock smallholders. Conversely, involvement in jatropha production does not have a statistically significant positive effect on household food security for both workers and smallholders. Regression models indicate that the factors driving food security indicator levels vary between study sites. Wealth indicators influence food security indicators in several sites, but the absolute level of income plays a smaller role, while income stability/regularity, access to credit and stable markets for selling sugarcane be important drivers as indicated by the strong effect of proxy variables on indicators.

Jatropha Curcas Biodiesel: A Lucrative Recipe for Pakistan’s Energy Sector

One of the greatest challenges of the 21st century is to fulfill the growing energy needs sustainably and cost-effectively. Among the different sources of energy, biodiesel is one of the alternative energy sources that has tremendous potential to become a major mainstream renewable energy mix. Jatropha is an important raw input for biodiesel that provides an ecological and sustainable solution for emerging greenhouse gas emissions over the other biomass feedstock. This paper critically evaluates different factors and presents a SWOT analysis (strengths, weaknesses, opportunities, and threats) and barriers to the adoption of Jatropha biodiesel. In Pakistan, the estimated production of Jatropha biodiesel is expected to be 2.93 million tons, that are calculated from available barren land and possible shortlisted suitable areas for Jatropha plantation. It is ~25% of the total import (11.84 million tons) of petroleum products, which can save ~$2 billion USD reserves of Pakistan. The cultivation of Jatropha on barren land is an environmentally and economically lucrative approach for Pakistan. This study has real implications for developing a policy framework related to the environment and socio-economic feasibility of Jatropha biodiesel production in Pakistan.

Land Suitability for Potential Jatropha Plantation in Malaysia

Malaysia has embarked on several initiatives and policies towards renewable energy for improving quality. Jatropha Curcas is an oil seed-bearing plant, which potentially yields as a source of energy in the form of biodiesel. However, research on the determination of the potentially suitable area of Jatropha plant can be allocated still limited. This study aims to carry out a land suitability study on the Jatropha plantation using the geospatial technique such as Geographical Information System (GIS) and remote sensing. To achieve the aim, the objectives of this study are to i) determine significant weightage of parameters for Jatropha plantation and ii) identify the suitable location Jatropha plantation. The study area is carried out at peninsular Malaysia, and five (5) variables such as rainfall, temperature, land-use, soil and elevation data were used to achieve the analysis. The analytical hierarchy process (AHP), in the combination of Geographical Information System (GIS) methods, was applied to compute the weightage of the selected criteria, which is in geospatial data types. A map of the potential Jatropha location was generated using the criteria weightage. This study can help the cultivation of Jatropha in suitable areas and may reduce the burden on fossil fuels. It can assist smallholder-based initiatives to promote Jatropha cultivation on farmer-owned to enhance their living circumstances.

Biology, Life Cycle and Damage Potential of Scutellera nobilis (Fabricius) (Hemiptera: Scutellaridae) on Jatropha curcas L. in Jammu (J&K), India

A native species of Mexico and tropical America, Jatropha curcas L. (Euphorbiaceae) is a perennial, multipurpose and drought resistant species, which is gaining importance commercially as a bio-diesel plant and is being intensively advocated for development of wastelands and dry lands throughout India. Contrary to the popular belief that toxicity of Jatropha curcas is sufficient deterrent for insects, several insect groups have overcome this barrier. Studies undertaken in Jammu revealed that Scutellera nobilis (Fabricius) (Hemiptera: Scutellaridae) causes extensive damage to Jatropha plantations. Various aspects of biology, life cycle and ecology of Scutellera nobilis were studied at Jammu, which revealed that the pest population remains abundant from April till November in the study area and the total life cycle of the pest lasts for about 30 - 36 days. This data can be used to keep the pest population in check, thereby, preventing the loss to plantation and to the economy on the whole. Being sap suckers, they feed upon all plant parts likely, but growing shoots and developing fruit are preferred resulting in the production of malformed and hollowed seeds. The feeding also leads to necrosis of the leaves and premature leaf fall. The present paper records first ever report on the biology and life cycle of Scutellera nobilis from Jammu region, which is an aim to design preventive measures against this pest to save the Jatropha plantations from being degraded.

Life Cycle Assessment of electricity generation from Jatropha oil in a short chain in Mali

Jatropha curcas is an inedible oil crop which can grow under semiarid climatic conditions. Its oil can be used straight as fuel to provide energy in remote areas to improve living conditions. The aim of this study is to assess the environmental impacts of the electricity generation from Jatropha oil under West African conditions, by means of a Life Cycle Assessment (LCA). These potential impacts are calculated for four crop managements and compared to the ones of a reference electricity generation from conventional diesel. Data used in this work are from Jatropha plantations set up in Mali since 2006.LCA results show that the potential benefits of the Jatropha systems are highly dependent on the crop management, especially for the fertilization strategy and the promotion of the oilcake. However, in all cases, the Jatropha systems have lower impacts than the reference diesel system by 75% to 96% for abiotic depletion, and by 80% to 97% for ozone layer depletion, and higher impacts by 260% to 1000% for eutrophication, and by 26% to 160% for acidification. In the best case, the Jatropha system can also have lower impacts than the reference system by 76% for climate change, and by 88% for photochemical oxidation.A methodological originality of this work is the inclusion of animal and human labour into the LCA framework. A first model is proposed for the accounting of energy consumption and GreenHouse Gases (GHG) emissions due to labour. Concerning energy consumption, labour is not negligible with a share from 14% to 50% of the total impact of the Jatropha systems; however the highest share of 50% corresponds to the scenarios with the lowest energy demand. CH4 emissions from livestock are also not negligible but second-order in this study since they account for 2% to 13% of total GHG emissions.

FABRICATION OF OIL EXTRACTION MACHINE FROM JATROPHA SEEDS AND BLENDING PROCESS FOR BIODIESEL

Diminishing fossil fuel resources, unstable/increasing prices of oil, environmental issues, global warming/climatic shifts, and allied problems have led the world to focus on alternate, environmental friendly, and renewable energy sources. Among many experimental candidates, production of biodiesel from Jatropha curcas L. has gained significant importance. More than 40 countries in the world are evaluating the potential of using this pure plant oil for manufacturing diesel. Biodiesel is a fuel type that has already been proven suitable for use in diesel engines. The non-edible vegetable oil of Jatropha curcas, which grows in tropical and subtropical climates across the developing world, promises a commercially viable alternative to diesel. Jatropha oil is renewable, environmental friendly and can be easily produced in rural areas. Countries of South-East Asia, such as Malaysia, they are going to start the establishment of Jatropha plantations assuming that Jatropha will be the main resource for biodiesel production. This paper presents the design and fabrication of an efficient Jatropha oil expelling machine. Further carrying out transesterification process on Jatropha oil to get Jatropha biodiesel.

Jatropha – Potential of biomass steam processing to convert crop residues to bio-coal and thus triple the marketable energy output per unit plantation area

Jatropha curcas cultivation is being undertaken mainly for fuel oil production, but it also results in biomass residues such as fruit husks, seed shell, seed cake or kernel meal, together making up >80% of the dry fruit weight. Additionally, plant biomass from crop management is also generated. The various biomass residue fractions have gross energy contents ranging from 13 MJ/kg to over 18 MJ/kg. The conversion of these residues into marketable products would contribute to broadening the circumstances under which the jatropha crop is profitable. Biomass Steam Processing (BSP) is a steam assisted thermochemical conversion process, which aims to increase the energy density of lignocellulosic feedstock. Basically, during this process biomass is heated to a temperature of 250–400 °C in a steam atmosphere at atmospheric pressure. It converts biomass residues efficiently into bio-coal in a relatively short time period of about 1 h. In the current investigation, BSP was deployed to transform different potential jatropha crop and seed processing residues into marketable high quality bio-coal. The energy density of jatropha residues could be raised considerably, resulting in an estimated total marketable energy yield of 90 GJ per year per hectare of a 5-year-old jatropha plantation compared to a total yield of 30 GJ per year when jatropha oil alone is marketed, as currently practiced.

Biofuels versus food: Understanding the trade-offs between climate friendly crop and food security

The present paper analyzes the impact of Jatropha plantation on food production in North East India. It is based on the primary data collected from 281 farmers, consisting of the present and past Jatropha growers, from Assam and Arunachal Pradesh through multistage random sampling technique. Food production in the region is hypothesized to be affected by agricultural land conversion and labor diversion from food to Jatropha plantations. Non-parametric tests and Probit models were used to examine the effects of Jatropha plantation on food production. The results show that the probability of a reduction in food production does indeed increase if either agricultural land is converted or labor is diverted from food production to Jatropha. However, the conversion of agricultural land and diversion of labor from food production to Jatropha plantation is more likely among the past-growers. Thus, it appears that while Jatropha plantation may set back the food production in the short-run, this adverse effect may reduce in the long-run. Regulation on land use pattern along with higher agricultural productivity may minimize the intensity of land conversion and labor diversion to Jatropha. Moreover, use of degraded land, intercropping, and third-generation biofuels may reduce the food versus biofuels conflict.

An assessment of economic viability of jatropha plantation in North East India

PurposeThis paper aims to analyze the economic viability of jatropha plantation in North East India.Design/methodology/approachEconomic viability is measured through the net present value and the benefit–cost ratio (BCR) at four different production standards along with four different prices of jatropha seed.FindingsAt a very low price and small production, jatropha plantation is economically not feasible. However, when the price of seed increases from INR 5 to 8, BCRs become greater than 1, provided that the discount rate is less than equal to 8 per cent. The minimum threshold of BCR indicates that the threshold of 1.5 BCR at a production level of 1.5 tons/ha can be achieved with a combination of seed price of INR 10 per kg and a discount rate of 1 to 3 per cent. Thus, jatropha cultivation is economically viable but not highly profitable.Research limitations/implicationsPresent study analyzes the economic viability of jatropha plantation from purely financial point of view. Social cost and benefit of energy crop plantation is not included in the study. This suggests to adopt social cost–benefit analysis to evaluate the overall feasibility of plantation crops in future studies.Originality/valueThis paper contributes to the academic literature of economic viability of energy plantation crops. Economic viability of jatropha plantation is shown in different cost and revenue conditions with statistical evidences.

Jatropha (Jatropha curcas) based intercropping systems: An alternate land use for rehabilitation of degraded sodic lands

A field study was conducted to evaluate the performance of jatropha based intercropping model as an alternate land use for rehabilitation of degraded sodic lands. Cultivation of Jatropha curcas L. as monocropping has not been proven economically viable because of its late fruiting and poor yield. A small and resource poor farmer having sodic soils can't wait for at least five years to get income. Therefore, the present study was conducted to replace monoculture of jatropha with intercrops in between jatropha plantation in sodic soils to optimize land use efficiency. Study revealed that the plantation of jatropha at 3 m apart and inter- cultivation of sweet basil - matricaria cropping sequence for four years was highly economical than the planting at 3×2m spacing and other tested crop rotations. Soil physicochemical and biological properties in sweet basil - matricaria with jatropha L. as main crop were better than rest of the cropping sequences evaluated. Soil microbial biomass carbon (MBC) was also higher with sweet basil-matricaria cropping sequence followed by sorghum wheat and maize-linseed. The study shows that inter cultivation of Jatropha in sodic soils encouraged biological activities in the rhizosphere. Inter-cultivation of medicinal and aromatic crops under Jatropha plantations for four years was found to be an alternate land use sequence to obtain higher income than the sole plantation of Jatropha in sodic soils. Soil health improvement due to intercropping can provide a better environment for cultivation of highly remunerative crops in future.

Macroeconomic and Distributional Impacts of Jatropha Based Biodiesel in Mali

Mali has introduced a program to produce biodiesel using jatropha, a shrub widely available throughout the country. The aim of the program is to partially substitute diesel, which is entirely supplied through imports, with domestically produced biodiesel. In this paper, we use a computable general equilibrium (CGE) model and a microsimulation model to analyze macroeconomic and distributional impact of a hypothetical expansion of jatropha based biodiesel industry in Mali. We find that the expansion of biodiesel industry (i.e., both jatropha farming and oil conversion), would increase GDP, though slightly, if idle lands are utilized for jatropha cultivation. However, the expansion of jatropha would cause slight loss in GDP if the existing agriculture land is used for jatropha cultivation. The distributional results are slightly different. We find that rural poverty would decrease no matter whether idle lands or existing agricultural lands are used for jatropha plantation, although the percentage reductions in rural poverty are higher in the former compared to the latter case. Our results indicate that if governments plan to promote jatropha biodiesel they should not allow jatropha to compete with food staples on the existing land. Policies should be targeted to utilize the idle lands which have not been used for any productive use.

Status of Jatropha plants farming for biodiesel production in Rwanda

This study investigated the status of Jatropha plants farming for biodiesel production in Rwanda. A total of 73 Jatropha farmers from five sectors namely, Kigarama, Kigina, Kirehe, Mahama and Nyamugali in Kirehe district, Eastern Province, were selected. The study examined eight key parameters that determine the status of Jatropha plants farming. These parameters are classification of Jatropha farmers, methods for Jatropha plants growing, government strategy on providing Jatropha quality seeds or seedlings to farmers, government involvement to initiate local farmers to cultivate Jatropha plants for biodiesel production, knowledge level of the farmers on Jatropha plants farming, Jatropha seeds yield, perception level of investing on Jatropha plants farming and opinions of the key players in the biodiesel project. Through interviews and questionnaires, information was gathered and analysed using both qualitative and quantitative methods.Result indicates that majority of the farmers (82%) in the five sectors reported that they were farming Jatropha plants as individual farmers while about 18% indicated that they were cultivating Jatropha plants as cooperatives. Majority of the farmers (70%) used agro-forestry farming technique due to shortage of farm lands. It was also revealed that most of the farmers (55%) have little knowledge on growing Jatropha plants. With regards to farmers using quality Jatropha seeds or seedlings, most farmers (93%) indicated that the government has not provided Jatropha seeds or seedlings. On the other hand, majority of the farmers (80%) stated that there have been very low involvements of the government to initiate farmers to cultivate Jatropha plants for biodiesel production project.In terms of Jatropha seeds yield, majority of the farmers (63%) in the five sectors rated Jatropha seed production level as low (between 1.1 and 2.9 t/ha/year) while about 33% stated that it was very low (between 0 and 1 t/ha/year). This was attributed to lack of reliable markets, low level of sensitisation, lack of preliminary studies on suitable areas for Jatropha plantation, lack of policy and institutional framework on biofuels, shortage of farm lands for intensification of Jatropha framing and low soil adaptation of the Jatropha plants. Due to low production level and lack of reliable markets, 71% of the total respondents considered Jatropha plants farming as a very low investment.Since there is no biodiesel production at the moment which would have created a reliable market for Jatropha seeds, Jatropha farming for biodiesel production in Rwanda is not viable. It is recommended that the government should carry out a feasibility study to generate knowledge on growth performance of various Jatropha species under the prevailing environmental conditions. In addition, due to shortage of land farms, the government should undertake economic assessment of growing Jatropha trees as hedges.

The role of chiefs in large-scale land acquisitions for jatropha production in Ghana: insights from agrarian political economy

Ghana experienced a surge in large-scale land acquisitions in the past decade spearheaded by the bioenergy crop jatropha. To accommodate such acquisitions, small and medium-sized land holdings were consolidated to develop large parcels of land that could accommodate large-scale investments. Chiefs have been an important player in these processes as they are supposed to be the custodians of land in Ghana. However, they often engage with such land acquisition processes in a counterproductive manner, deeply affecting their outcomes. Chiefs often act as the gatekeepers of large-scale land acquisitions, helping foreign donors/investors and the state steer the institutional landscape of land tenure, which is not only complicated but also prone to social conflicts. In order to unravel the exact roles that chiefs have played in such processes (and the motivations behind their actions) we adopt an agrarian political economy framework based on the five key questions: “who owns what”, “who does what”, “who gets what”, “who interacts with whom” and “participation by whom in what”. To answer these questions, we conduct interviews with chiefs, experts and local households around five collapsed jatropha plantations in Ghana. Our empirical analysis suggests that chiefs often went beyond their customary roles as land custodians, by occasionally acting as land owners/sellers, expropriators, negotiators, receivers of compensation, and sources of conflict. These roles are to an extent an outcome of the weak, undocumented and largely discretionary land administration system of Ghana, which allows chiefs benefit by bypassing both customary and statutory land laws. Chiefs were often motivated by expected economic gains for themselves at the expense of the communal interests. On some cases this unconstructive role catalysed the collapse of the jatropha investments. These suggest the need for deep land policy reforms within the land administration system of Ghana. While the recent adoption of guidelines for large-scale land acquisitions promoted by the government of Ghana is a good start, land policy reforms should go deeper. Further reforms would be needed to strengthen the current legislation in terms of harmonizing all land laws, as well as outlining explicit directives for land negotiations, compensation (including defining the rightful recipients of compensation) and the effective evaluation of large-scale land acquisitions.

Characterization of Jatropha curcas honeys originating from the southern highlands of Madagascar

Jatropha curcas, an entomophile Euphorphiaceae is an important bio-energy plant cultivated in some of the world's poorest countries. Commercial use of Jatropha honey could significantly improve the economic situation of plantations. This study evaluates the quality of 174 Jatropha honeys collected on Madagascar. Melissopalynology revealed a large pollen diameter of 87 μm and a verrucous exine causing under-representation of Jatropha pollen in monofloral honey. Characteristic physico-chemical parameters in the honeys were: pH 4.4; free acidity 18.2 meq/kg; electrical conductivity 756 μS cm−1; diastase number 12.9 DZ; total phenolic content 45 mg EGA/100 g; antioxidant capacity 56%. Fructose content (477 g/kg) was higher than glucose (326 g/kg) in all samples. Minor sugars were sucrose (16 g/kg), erlose (6 g/kg), turanose (5 g/kg), trehalose, maltose, and maltotriose (4 g/kg each). Proline (313.2 mg/kg) was the dominating free amino acid (49–79% of total amino acids), whereas asparagine, arginine and cysteine were not detected. Phorbolesters were not detected in any of the analyzed honey samples. Monofloral Jatropha honey meets the quality standards of the Codex Alimentarius in all aspects. Hence beekeeping on Jatropha plantations not only improves plant pollination and oil yield, but also generates additional income.

Greenhouse gas and energy balance of Jatropha biofuel production systems of Burkina Faso

Jatropha curcas has been introduced as a low-cost energy crop in Burkina Faso for the production of straight vegetable oil (SVO) and biodiesel. It is cultivated in different plantation systems including smallholder inter-plantings with annual crops, large-scale monoculture, afforestation on marginal land, in traditional hedge systems along contour stone walls, and in living fences. We performed Life Cycle Assessment of these Jatropha systems using empirical data on yields and carbon stocks, and accounting for changes in agro-ecosystem provisioning and regulating services that occurred after the land conversion to Jatropha. The study found that all J. curcas production pathways substantially reduced greenhouse gas emission (68–89%) and saved energy (65–90%) compared to diesel fuel. Highest values are achievable under the assumption that by-products (husks, seed cake, glycerin) are used for energy generation. The decentralized production of SVO supplied by feedstocks from intercropping and hedgerow systems seems to be most promising option. However, very low land-use efficiency (6.5–9.5 GJ ha−1 production) characterized Jatropha intercropping and monoculture plantations, rendering the plant a competitor to food crops and increasing the risk of conversion of savanna land to Jatropha cultivation. Jatropha plantings on marginal lands largely failed. High labor requirements constrain integration of Jatropha plantation systems within small farmholdings. Currently, the traditional hedge systems show the lowest land-use replacement potential and labor needs while providing multiple ecosystem services, but alone cannot satisfy rural energy needs. In order to reach energy supply targets without claiming more land and compromising other ecosystem services, the J. curcas plantation systems in Burkina Faso need to be made more efficient through plant breeding and improved agronomic management.

Spatio-temporal spread of foot rot (Lasiodiplodia theobromae) in Jatropha curcas L. plantations in Yucatan, Mexico

Foot rot is one of the most important phytosanitary problems in Jatropha (Jatropha curcas L), causing plant death. The objective of this paper was to determine the epidemiology of foot rot. Consequently, the spatiotemporal spread of the disease and its relationships with the environment was determined in two commercial Jatropha plantations (Fs1 and Nb) in 2015. Incidence of the disease in the period from March to November was 0.43% to 4.76% for plot Fs1 and for plot Nb it was 2.54 to 16.66%, with a gradual increase in the first months and a faster increase in the last months in both plantations. Monthly incidence was adjusted to a linear form of three non-flexible models and the results showed that the Gompertz model provided a better explanation (R2 = 0.099) for the advance of foot rot in the two plots, with an apparent rate of increase for plots Fs1 and Nb of 0.0034 and 0.047 respectively. The disease progresses speed is associated with higher temperatures and greater relative humidity (p ≤ =0.05). Moreover, the dispersion of the disease, calculated by the Morisita index, showed a random spread in the first stages of the epidemic and formed aggregates in subsequent stages. The analysis of auto correlation and the geospatial graphs showed that plants with the diseases were grouped in numbers of 4 to 6 in a north to south direction. The implications of the epidemiological behavior in the management of the disease will be discussed.