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In recent years, aluminium (Al) matrix reinforced with graphene-based nanomaterial (GN) composites (AGNCs) have emerged as a potential candidate for various applications due to their lightweight combined with excellent mechanical, tribological, thermal, and electrical properties. This paper is intended to provide a comprehensive and critical review of the state-of-the-art research activities related to the processing, properties, and applications of AGNCs. The review begins by highlighting the need for “lightweighting” and AGNCs, followed by a short introduction to the structure and properties of GNs. It covers the current challenges in the processing of AGNCs, such as low wettability, interfacial reactions, and agglomeration of GNs. Different consolidation and post-processing techniques used for the fabrication of AGNCs are also presented. Subsequently, the effect of GN addition on properties of AGNCs is critically reviewed. Different micromechanical models used for quantifying the strengthening of AGNCs aided by various strengthening mechanisms are also elucidated. More importantly, based on the reported properties, the potential and promising applications of AGNCs in various industries, such as automobile, aerospace, space, electrical, electronics, and energy systems, have been proposed. Afterwards, the current understanding of AGNCs is thoroughly summarized. Finally, directions for future research in the field of AGNCs have been suggested. © 2022 Elsevier Ltd.

In recent years, aluminium (Al) matrix reinforced with graphene-based nanomaterial (GN) composites (AGNCs) have emerged as a potential candidate for various applications due to their lightweight combined with excellent mechanical, tribological, thermal, and electrical properties. This paper is intended to provide a comprehensive and critical review of the state-of-the-art research activities related to the processing, properties, and applications of AGNCs. The review begins by highlighting the need for “lightweighting” and AGNCs, followed by a short introduction to the structure and properties of GNs. It covers the current challenges in the processing of AGNCs, such as low wettability, interfacial reactions, and agglomeration of GNs. Different consolidation and post-processing techniques used for the fabrication of AGNCs are also presented. Subsequently, the effect of GN addition on properties of AGNCs is critically reviewed. Different micromechanical models used for quantifying the strengthening of AGNCs aided by various strengthening mechanisms are also elucidated. More importantly, based on the reported properties, the potential and promising applications of AGNCs in various industries, such as automobile, aerospace, space, electrical, electronics, and energy systems, have been proposed. Afterwards, the current understanding of AGNCs is thoroughly summarized. Finally, directions for future research in the field of AGNCs have been suggested. © 2022 Elsevier Ltd.

In recent years, aluminium (Al) matrix reinforced with graphene-based nanomaterial (GN) composites (AGNCs) have emerged as a potential candidate for various applications due to their lightweight combined with excellent mechanical, tribological, thermal, and electrical properties. This paper is intended to provide a comprehensive and critical review of the state-of-the-art research activities related to the processing, properties, and applications of AGNCs. The review begins by highlighting the need for “lightweighting” and AGNCs, followed by a short introduction to the structure and properties of GNs. It covers the current challenges in the processing of AGNCs, such as low wettability, interfacial reactions, and agglomeration of GNs. Different consolidation and post-processing techniques used for the fabrication of AGNCs are also presented. Subsequently, the effect of GN addition on properties of AGNCs is critically reviewed. Different micromechanical models used for quantifying the strengthening of AGNCs aided by various strengthening mechanisms are also elucidated. More importantly, based on the reported properties, the potential and promising applications of AGNCs in various industries, such as automobile, aerospace, space, electrical, electronics, and energy systems, have been proposed. Afterwards, the current understanding of AGNCs is thoroughly summarized. Finally, directions for future research in the field of AGNCs have been suggested. © 2022 Elsevier Ltd.

In recent years, aluminium (Al) matrix reinforced with graphene-based nanomaterial (GN) composites (AGNCs) have emerged as a potential candidate for various applications due to their lightweight combined with excellent mechanical, tribological, thermal, and electrical properties. This paper is intended to provide a comprehensive and critical review of the state-of-the-art research activities related to the processing, properties, and applications of AGNCs. The review begins by highlighting the need for “lightweighting” and AGNCs, followed by a short introduction to the structure and properties of GNs. It covers the current challenges in the processing of AGNCs, such as low wettability, interfacial reactions, and agglomeration of GNs. Different consolidation and post-processing techniques used for the fabrication of AGNCs are also presented. Subsequently, the effect of GN addition on properties of AGNCs is critically reviewed. Different micromechanical models used for quantifying the strengthening of AGNCs aided by various strengthening mechanisms are also elucidated. More importantly, based on the reported properties, the potential and promising applications of AGNCs in various industries, such as automobile, aerospace, space, electrical, electronics, and energy systems, have been proposed. Afterwards, the current understanding of AGNCs is thoroughly summarized. Finally, directions for future research in the field of AGNCs have been suggested. © 2022 Elsevier Ltd.

Mycotoxins are toxic secondary metabolites produced by fungi on agricultural produce. Mycotoxins can be cytotoxic, genotoxic, mutagenic, and teratogenic, and they are persistent threats to human and animal health. Consumption of mycotoxin-contaminated maize can cause cancer and even sudden death. Health hazards can also occur from consuming products from animals fed with mycotoxin-contaminated feed or forage. The main mode of spread of mycotoxigenic fungi is through air-borne spores originating from soil or plant debris, although some fungi can also spread through infected seed-to-seedling transmission, ultimately followed by contamination of the harvestable product. This perspective assesses opportunities to prevent mycotoxigenic fungal infection in maize seeds produced for sowing as an important starting point of crop contamination. A case study of Nigeria showed infection in all tested farmer-produced, seed company, and foundation seed samples. A schematic overview of the formal and informal seed systems is presented to analyze their contribution to fungal infection and mycotoxin contamination in the maize value chain, as well as to set criteria for successful control. We recommend an integrated approach to control mycotoxigenic fungal infection, including resistant varieties and other control methods during seed production, grain production, and grain storage, with an important role in maintaining seed health.

Cassava is the most important vegetatively propagated food staple crop in Africa. Even if its vegetative propagation through stem cuttings has many advantages, it also represents its Achilles heel. Pathogens are passed from one generation to the next and can easily accumulate, threatening cassava production. Two viral diseases are currently considered to be the greatest global threat to cassava production in Africa. Faced with the gravity of this situation, 43 scientists from African national and regional institutions and international agricultural research centres met in Saint-Pierre, La Réunion Island from 10 to 13 June 2014, to contribute to the surveillance and control of cassava diseases and pests that threaten the food security and livelihoods of millions Africans. The main action was to consolidate and develop a global alliance against cassava diseases in Africa and a strategic action plan with several international initiatives for the coming years. Firstly, the establishment of a Pan-African Cassava Surveillance Network (PACSUN) with an interactive website and an International Cassava Transit Site (ICTS) in La Réunion. Secondly, the development of diagnostic technologies to better identifying viruses, bacteria and vectors, and a comprehensive educational and training plan to support all these activities. (Texte intégral)

Cassava is the most important vegetatively propagated food staple crop in Africa. Even if its vegetative propagation through stem cuttings has many advantages, it also represents its Achilles heel. Pathogens are passed from one generation to the next and can easily accumulate, threatening cassava production. Two viral diseases are currently considered to be the greatest global threat to cassava production in Africa. Faced with the gravity of this situation, 43 scientists from African national and regional institutions and international agricultural research centres met in Saint-Pierre, La Réunion Island from 10 to 13 June 2014, to contribute to the surveillance and control of cassava diseases and pests that threaten the food security and livelihoods of millions Africans. The main action was to consolidate and develop a global alliance against cassava diseases in Africa and a strategic action plan with several international initiatives for the coming years. Firstly, the establishment of a Pan-African Cassava Surveillance Network (PACSUN) with an interactive website and an International Cassava Transit Site (ICTS) in La Réunion. Secondly, the development of diagnostic technologies to better identifying viruses, bacteria and vectors, and a comprehensive educational and training plan to support all these activities. (Texte intégral)

Following the open comment period for MusaNet and ProMusa members in September 2015, the ''BSV Position Paper'' was finalized and is now available here. The purpose of the position paper was to propose a strategy for the distribution of germplasm containing infective endogenous BSV in the B genome, while minimising any risk associated with the distribution of BSV to the recipient country. Comments on the paper were well received and addressed by the taskforce. Please click here for a summary of the comments and responses. The next step is for the International Transit Centre (ITC) to develop an official procedure for the distribution of eBSV infected germplasm based on the position paper. This will be discussed in the MusaNet Expert Committee and reviewed by the taskforce (pictured below) that developed the position paper. The strategy will be implemented after all of the ITC accessions containing the B genome are screened and cleaned if necessary. This is currently being carried out by CIRAD and the University of Liege, Gembloux Agro-Biotech, and is expected to be completed by the end of 2016. If you have any questions or comments, please contact Rachel Chase at r.chase@cgiar.org.

Following the open comment period for MusaNet and ProMusa members in September 2015, the ''BSV Position Paper'' was finalized and is now available here. The purpose of the position paper was to propose a strategy for the distribution of germplasm containing infective endogenous BSV in the B genome, while minimising any risk associated with the distribution of BSV to the recipient country. Comments on the paper were well received and addressed by the taskforce. Please click here for a summary of the comments and responses. The next step is for the International Transit Centre (ITC) to develop an official procedure for the distribution of eBSV infected germplasm based on the position paper. This will be discussed in the MusaNet Expert Committee and reviewed by the taskforce (pictured below) that developed the position paper. The strategy will be implemented after all of the ITC accessions containing the B genome are screened and cleaned if necessary. This is currently being carried out by CIRAD and the University of Liege, Gembloux Agro-Biotech, and is expected to be completed by the end of 2016. If you have any questions or comments, please contact Rachel Chase at r.chase@cgiar.org.

Soybean production in Tanzania is steadily increasing, driven by growing demand from feed and livestock producers and also for human consumption. Soybean production area has increased from 795 ha in 2003 to 4,100 ha in 2013 (FAO 2014). Major soybean production is in the Morogro, Ruvuma, Iringa, and Mbeya regions. During a soybean rust disease survey conducted in May 2014 in Morogoro in the southern highlands of Tanzania, soybean plants with phyllody and witches’-broom disorder typical of phytoplasma infection was observed on cultivar, Uyole Soya#1 in a farmer’s field at Msufini village (6°17′0.099″ S; 37°28.791″ E). Symptoms consisted of shoot proliferation, reduced size of the leaflets and petiole, proliferation of axillary shoots with shortened internodes, phyllody, and viriscence. About 50% of the plants assessed (n = 20) from one plot in a farmer’s field were infected. Symptomatic and asymptomatic leaves were collected for total genomic DNA extraction and PCR amplification using Candidatus phytoplasma universal primer pair P1 and P7 for 16S-23S ribosomal RNA encoding region (Sharmila et al. 2004). PCR amplicons of expected size (∼1,700 bp) resulted from the templates of the symptomatic samples only. They were directly sequenced in both orientations and the nucleotide sequence was submitted to GenBank (Accession No. KP205526). A BLASTn search revealed that the phytoplasma sequences had a nucleotide sequence identity of 99% with those of 16SrII group phytoplasma associated with phyllody and witches’-broom disease of soybean in Malawi (HQ845208) and Mozambique (HQ840717). Phylogenetic analysis revealed the clustering of these strains with members of 16SrII group. The virtual restriction fragment length polymorphism (RFLP) pattern derived from these sequences using iPhyClassifier software (Zhao et al. 2009) was similar to the reference pattern of the 16SrII subgroup C (cactus phytoplasma, AJ293216), with a pattern similarity coefficient of 0.99. Previous reports of