<i>Jatropha curcas</i> for rural development in Sub-Saharan Africa: agronomic and socio-economic sustainability

In the forthcoming years, 1-2 million hectares of Jatropha curcas L. are expected to be annually planted, reaching 12.8 million hectares worldwide by 2015. This considerable expansion is due to its products and by-products multiple uses and its amazing adaptability. J. curcas oil extracted by seeds is a promising renewable feedstock for biodiesel production and, together with the oil extraction by-products, it can be used in as cooking/lighting fuel, bio-pesticide, organic fertilizer, combustible fuel, and for soap making, contributing to mitigate environmental problems in developing countries. Nevertheless, J. curcas is not a “miracle tree”. Indeed, the full potential of J. curcas is far from being achieved and its talents are still to be supported by scientific evidences. The present Ph.D. thesis aims to: (i) detail each phase of J. curcas productive chain from sowing to biodiesel and by-products, in order to logically organize the knowledge around J. curcas system, and to compare potentialities and criticalities of J. curcas; (ii) assess the socio-economic and environmental sustainability of smallholder local and decentralized J. curcas plantations, promoted by cooperation rural development cooperation projects in Sub-Saharan Africa; (iii) explore the effects of different pre-sowing treatments on germination behaviour of J. curcas seeds and to assess the growth of the seedlings; and (iv) investigate physiological responses, in term of growth and photosynthesis, of J. curcas seedlings exposed to a severe soil drought stress. The conducted studies confirmed that community-based initiatives on J. curcas plantation could positively contribute to the rural livelihoods in developing countries. However, it is still necessary to fill some knowledge gaps and much more research is required for guaranteeing a full socio-economic and environmental sustainability of J. curcas used as a trigger of rural development in Sub-Saharan Africa.</br

The Euro-Mediterranean partnership: a participatory demonstration project to fight desertification in Morocco and Tunisia

A participatory demonstration project on desertification mitigation and rural development has been launched in Northern Africa under SMAP Programme (Short and Medium-term priority environmental Action Programme) financed by the European Union. The project, whose title is "Demonstration Project on Strategies to Combct Desertification in Arid Lands with Direct Involvement of Local Agro-pastoral Communities in North Ajrica ". is carried out in sensitive regions in Morocco and Tunisia with the coordination of the NRD of the University of Sassari (Italy) and the partnership of the Agriculture Ministries of Morocco and Tunisia. The project involves restoration of vegetation cover with drought resistant perennial forage species (Opunti, Atriplex, Acaci, etc.) in highly degraded Rangelands, to mitigate desertification processes and to improve rangelands productivity. The areas are located in regions characterised by rural poverty, food dependency and land abandoning: here urgent measures are needed to promote optimisation of resource management in view of a sustainable development. This is a concrete demonstration project supported by the direct involvement of local communities. Successful actions already carried out in this field by the participants of the project as well as by other Mediterranean Countries. has been taken into Account, re-elaborated and exploited thus promoting South / South co-operation and exchange of knowledge. Participation of all actors and especially of local communities is the key point in all the phases of the project and is strengthened by means of dissemination and sensitisation campaigns and by training courses. Only if, at the end of the project, all actors will own/share all choices made and the technology used, will interventions be "sustainable"

Approccio partecipativo per lo sviluppo integrato e la gestione delle zone marginali in Nord Africa: progetto dimostrativo di lotta alla desertificazione in Marocco e Tunisia

Nelle zone aride e semiaride, l’agricoltura e la pastorizia rappresentano fondamentali risorse per la sussistenza delle popolazioni locali. Nonostante la loro importanza strategica, in queste aree, le produzioni risultano sovente limitate e irregolari, manifestando un grosso limite allo sviluppo delle attività agropastorali. Gli ecosistemi dei territori interessati si presentano spesso fragili, a causa dell’azione combinata di fattori climatici e delle attività umane. L'aratura e la rimozione indiscriminata della vegetazione, insieme all’irregolarità e all’insufficienza delle piogge sono spesso responsabili di fenomeni di degrado dei suoli, distruzione su grande scala della copertura vegetale e desertificazione. La crescente domanda di foraggio per gli allevamenti, di gran lunga superiore alla produttività dei pascoli (Le Houerou, 1990; 2000), ha provocato un aumento della pressione sul pascolo e la messa in coltura ad orzo di terre tradizionalmente adibite esclusivamente a pascolo, causando una accelerazione dei fenomeni di degrado del suolo (Abu Zenat et al. 2004). Inoltre, si è evidenziato un impoverimento qualitativo dei pascoli, dove le specie di alto valore foraggero sono spesso sostituite da piante meno produttive, meno appetibili e meno nutrienti di quelle originali (Juneidi and Abu-Zanat, 1993). In questo contesto, l’impianto di arbusti foraggeri garantisce la copertura vegetale del suolo, offrendo protezione contro l’erosione e rappresenta una potenziale risorsa di foraggio e legna da ardere (Mulas e Mulas, 2004). Le specie Opuntia ficus indica, particolarmente tollerante all’erosione idrica ed eolica (Nefzaoui et al. 2000), e Atriplex nummularia, perfettamente adatta ai climi mediterranei aridi o semiaridi (Hyder ed Akil, 1987), sono le più impiegate nelle regioni del Nord Africa e Medio Oriente. In questo lavoro si riportano i risultati di un intervento di sviluppo integrato, basato sull’impianto di Opuntia ficus indica e Atriplex sp.pl., nell’ambito del progetto europeo SMAP II “Demonstration Project on Strategies to Combat Desertification in Arid Lands with Direct Involvement of Local Agropastoral Communities in North Africa ” coordinato da NRD-UNISS e realizzato in aree aride e semiaride degradate di Marocco e Tunisia

Participatory approach for integrated development and management of North African marginal zones: demonstrative plan to fight desertification in Morocco and Tunisia

A demonstrative and participatory development project on desertification mitigation and rural development has been launched in Northern Africa under SMAP Programme (Short and Medium-term priority environmental Action Programme) financed by the European Union. The project, which title is Demonstration Project on Strategies to Combat Desertification in Arid Lands with Direct Involvement of Local Agro-pastoral Communities in North Africa, is carried out in sensitive regions of Morocco and Tunisia with the coordination of the Nucleo Ricerca sulla Desertificazione (NRD, Desertification Research Center) of the University of Sassari (Italy) and the partnership of Morocco and Tunisia Agriculture Ministries. The areas concerned are located in regions characterised by rural poverty, food dependency and land abandoning where urgent measures are needed to promote optimisation of resource availability and management for a sustainable development. The project involves direct desertification mitigation by vegetation cover restoration, with drought resistant perennial forage species (Opuntia ficus-indica, Atriplex nummularia and Acacia saligna) in highly degraded rangelands in order to mitigate desertification processes while improving rangelands productivity; and adopts measures for local population technical capacities building through training sessions related to all project activities, and making it a concrete demonstration supported by the direct involvement of local communities. Successful actions already carried out in this field by the participants of the project as well as by other Mediterranean countries, has been taken into account, re-elaborated and exploited, thus promoting south/south co-operation and exchange of knowledge. Participation of all actors and especially of local communities is the key point in all phases of the project and is strengthened by means of dissemination and sensitisation campaigns and by training courses. At the end of the project, all actors own/share all choices made and the technology used participating thus to the intervention sustainability

Physiological Responses to Drought Stress in Jatropha curcas Seedlings

Aims: The aim of the study was to investigate the physiological mechanisms of Jatropha curcas seedlings exposed to drought and the possible influence of seedling age. Study Design: A pot experiment was carried out using a completely randomized design with two seedling ages (2- and 3-month-old seedlings), two treatments per age (Watered: fully irrigated, and Unwatered: Not irrigated), six replicates (24 pots). Place and Duration of Study: The experiment was performed in a greenhouse facility located at the Experimental Station “Mauro Deidda” (Department of Agriculture of University of Sassari) at Ottava (Sassari, Italy) between June and September 2011.Methodology: To investigate the responses of 2- and 3-month-old J. curcas seedlings exposed to drought stress on 4th, 8th, 12th, 19th, and 26th day from treatment’s beginning, leaf and soil water content, biometric, gas exchange, and chlorophyll a fluorescence measurements were performed; on 26th day from treatment’s beginning, biometric destructive measurements were carried out. Results: Results support the hypothesis that J. curcas is appropriate to be cultivated in areas with limited water availability or prolonged periods of drought and highlight that mechanisms of drought response are highly influenced by seedling age. J. curcas seedlings maintained a good leaf water status by means of an effective stomatal closure, associated with a reduced aboveground growth and an increased root:shoot ratio. Under drought stress, 2-month seedlings showed a higher allocation of resources to roots compared to 3-month seedlings. Drought resulted in more detrimental effects on the photosynthetic response of 3-month seedlings, inducing the reduction of stomata conductance and the loss of photosystem II integrity. 2-month seedlings were instead able to activate mechanisms of drought tolerance through the activation of excess energy dissipation mechanisms. Conclusion: In the early stage of crop establishment, the transplanting of J. curcas 2-month seedlings proved to be more effective in order to avoid water stress related consequences

Modeling bio-engineering traits of Jatropha curcas L.

The wide distribution of Jatropha curcas L. in tropical areas provides the opportunity to use this plant for improving slope stability and controlling erosion. To determine the effectiveness of Jatropha curcas L. as a bio-engineering plant we measured stem diameter and height of 1, 3, 5, 6, 18, and 36 month-old plants, and root distribution at 6, 18, and 36 months by full excavation of the root system. We also measured in the laboratory the elastic modulus and maximum tensile force of 50 roots. These data were used to calibrate a weighted log-likelihood root distribution model and a root reinforcement model. Models were coupled to estimate root reinforcement at stand scale over a three year period as a function of the plantation's tree density. Our results of root distribution indicate a rapid decrease of root diameter along the root length leading to rapidly decreasing root reinforcement with distance from the stem. Minimal root reinforcements at 0.5 m from the stem is about 1 and 11 kPa for 18 and 36-month old plants, respectively. At 1 m from the stem only 36-month old plants provide any significant root reinforcement. Despite its relatively low root reinforcement relative to other larger tree species Jatropha curcas L. is a suitable bio-engineering plant because it easily propagates, grows fast, and is resilient. Root reinforcement in the first stage of growth needs high density plantation of up to 40,000 plants per hectare. This should then be followed by thinning down to 10,000 plants per hectare to optimize root reinforcement at 3 years age

State-of-the-art of the <i>Jatropha curcas</i> productive chain: from sowing to biodiesel and by-products

In the forthcoming years, 1–2 million hectares of Jatropha curcas L. are expected to be annually planted, reaching 12.8 million hectares worldwide by 2015. This considerable expansion is due to its products and byproducts multiple uses and its amazing adaptability. J. curcas oil extracted by seeds is a promising renewable feedstock for biodiesel production and, together with the oil extraction by-products, it can be used as cooking/lighting fuel, bio-pesticide, organic fertilizer, combustible fuel, and for soap making. The capability to grow on poor quality soils not suitable for food crop makes J. curcas a possible solution of all the controversies related to biodiesel production. Furthermore, J. curcas contributes to mitigate environmental problems, such as marginal land or abandoned farmland reclamation. Nevertheless, J. curcas is not a “miracle tree”: (i) the full potential of J. curcas is far from being achieved and its talents are still to be supported by scientific evidences; (ii) J. curcas capabilities are not easily exploitable and applicable simultaneously; (iii) its use is controversial and potentially unsustainable due to the current knowledge gaps about the impacts and potentials of J. curcas plantations. The aims of this review are to detail each phase of J. curcas productive chain from sowing to biodiesel and by-products, in order to logically organize the knowledge around J. curcas system, and to compare potentialities and criticalities of J. curcas, highlighting the agronomical, management, and environmental issues which should be still investigated

Potential and perspectives of <i>Jatropha curcas</i> plantations in marginal land of Ghana

Jatropha curcas L. is a perennial drought-resistant plant well adapted to marginal lands in arid and semiarid and tropical regions (Divakara et al. 2010). J. curcas is a valuable multipurpose crop and has recently gained lot of importance for the biodiesel production by oilseed and secondary products such as soap, fertilisers, bio-pesticides, cosmetics, and medicine. Furthermore, this energy crop offers the ecological advantage to mitigate soil degradation and desertification and to reclaim wasteland (Achten et al. 2008). Community-based Jatropha initiatives for local use, like small J. curcas plantations in marginal lands, agro-forestry systems with J. curcas intercropping, and agro-silvo-pastoral systems can be seen as efficient opportunities to increase rural development in developing countries. The integration of J. curcas into the rural economy at the village level is able to guarantee access to sustainable and affordable energy, increase rural income, create employment opportunities, and alleviate poverty. Although the global interest, Jatropha physiological properties and agronomic management practices are not thoroughly unravelled (Behera et al. 2010). This contribution will highlight some J. curcas scientific research challenges in the framework of an EU-AID international cooperation project implemented in the West Mamprusi District of the Northern Region of Ghana. Through J. curcas plantations, the main project aims are to provide adequate access and security of sustainable renewable energy supply to rural communities of Ghana, improving their livelihood, and to reduce desertification effects in degraded areas. Within this project, several agronomic experimental works are being carried out, in order to improve the knowledge of J. curcas agronomical management practices which could be specifically addressed to the Ghanaian context. Biometric measurement results of J. curcas propagation (direct seed vs pre-cultivated seedlings) and intercropping systems with cereals are shown