Analysis of rice plants exposed to a broad range of relatively low and environmentally realistic Cd concentrations showed that the root capacity to retain Cd ions rose from 49 to 79%, corresponding to increases in the external Cd

International audienceCashew is a tropical tree native to South America. Cashew was introduced in Asia and Africa by European explorers in the sixteenth century. The world production of cashew raw nuts reached 4.27 million tons in 2011. Vietnam is the top producer of raw nuts, and India is the first processor and exporter of processed nuts. The cashew market is expected to remain strong due to the high growth of production in some areas such as West Africa. For instance, a 40 % production increase has been observed in Nigeria over the last 5 years. There is also an increasing exploitation of high-value by-products, particularly those made of cashew nut shell liquid. Cashew production is potentially a major value for smallholder farmers from emerging countries. Despite the relevance of cashew production on the international markets and the potential for boosting rural development and reducing poverty, a complete review on cashew is missing. Therefore, we review here the cashew production chain. Our main conclusions are as follows: (1) several management practices, processing methods, and uses of products and by-products are published; (2) however, there is still a lack of knowledge due to a scattered research framework lacking integrated research programs; (3) smallholder farmers face major constraints limiting the development of cashew sector locally, ranging from difficult access to good planting material and training to lack of investment for innovating processing facilities; (4) among them, women, that account for up to 95 % of the workforce in the sector, receive lower wages and are subject to worse working conditions

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BackgroundAmong cereals, rice has a genetic propensity to accumulate high levels of cadmium (Cd) in grains. Xylem-mediated root-to-shoot translocation rather than root uptake has been suggested as the main physiological factor accounting for the genotypic variation observed in Cd accumulation in shoots and grains. Several evidence indicate OsHMA2 – a putative zinc (Zn) transporter – as the main candidate protein that could be involved in mediating Cd- and Zn-xylem loading in rice. However, the specific interactions between Zn and Cd in rice often appear anomalous if compared to those observed in other staple crops, suggesting that root-to-shoot Cd translocation process could be more complex than previously thought. In this study we performed a complete set of competition experiments with Zn and Cd in order to analyze their possible interactions and reciprocal effects at the root-to-shoot translocation level.ResultsThe competition analysis revealed the lack of a full reciprocity when considering the effect of Cd on Zn accumulation, and vice versa, since the accumulation of Zn in the shoots was progressively inhibited by Cd increases, whereas that of Cd was only partially impaired by Zn. Such behaviors were probably dependent on Cd-xylem loading mechanisms, as suggested by: i) the analysis of Zn and Cd content in the xylem sap performed in relation to the concentration of the two metals in the mobile fractions of the roots; ii) the analysis of the systemic movement of 107Cd in short term experiments performed using a positron-emitting tracer imaging system (PETIS).ConclusionsOur results suggest that at least two pathways may mediate root-to-shoot Cd translocation in rice. The former could involve OsHMA2 as Zn2+/Cd2+ xylem loader, whereas the latter appears to involve a Zn-insensitive system that still needs to be identified.Electronic supplementary materialThe online version of this article (doi:10.1186/s12284-016-0088-3) contains supplementary material, which is available to authorized users.

Geographic information is of key importance in promoting sustainable development in the rural and urban areas of the global South. Within the broader framework of information and communication technologies for development (ICT4D), geographic information systems (GIS) include a wide range of tools used for landscape representation, including community produced paper maps, participatory mapping, and computer based systems. The prominent role of GIS in the global South is acknowledged by many scholars and institutions. This entry explores applications relevant to global development, such as crisis mapping and location based services, presents methodologies and approaches for the deployment of GIS in the global South and highlights the main sustainability issues.