Sweetpotato, with a global annual planting area of approximately 9 million ha, is the second most important tropical root crop. It is widely adapted, being grown in more than 110 countries. Early maturing varieties grow in 3-4 months. It is hardy and has multiple uses. Both roots and foliage are edible and provide energy and nutrients in diets. Distinct quality types have different uses, with orange-fleshed sweetpotato being valued for its extremely high provitamin A content, and other types used in varied fresh and processed forms. Sweetpotato is easily bred, as true seed is easily obtained and generation cycles are short. There are five objectives of this review. The first objective is to briefly describe recent production and utilization trends by region; the second is to review knowledge about the origin and genetic nature of sweetpotato; the third is to review selected breeding objectives. The fourth objective is to review advances in understanding of breeding methods, including: (i) generation of seed through polycross nurseries and controlled cross breeding; (ii) a description of a new accelerated breeding approach; (iii) recent efforts to systematically exploit heterosis; and (iv) new approaches of genomic selection. The fifth objective is to provide information about variety releases during the past 20 years in West, East and Southern Africa, South Asia, East and South-east Asia, China and the Pacific.

Sweetpotato is a resilient food crop with great potential to contribute to reduced hunger in the world. Sweetpotato shows significant potential to contribute to reducing the Global Hunger Index, which reflects deficiencies in calories and micronutrients based on the components of hunger, undernourishment, under-five mortality rate, stunting and wasting. Its genetic diversity has been harnessed through breeding to increase vitamin A, iron, and zinc content, virus resistance and climate resilience for the world's food needs. Africa and India are the most food-insecure regions. The main objectives of this research were to: provide information and a knowledge base on sweetpotato breeding in Africa for biofortification of vitamin A, iron, and zinc, drought tolerance and virus resistance; recommend procedures for generating new breeding populations and varieties; and develop new tools, technologies and methods for sweetpotato improvement. The research was implemented between 2009 and 2020 in 14 collaborating African countries using introduced and local genotypes. The redesigned accelerated breeding scheme resulted in increased genetic gains for vitamin A, iron, zinc contents and virus resistance, and the release by sub-Saharan African countries of 158 varieties; 98 of them orange-fleshed; 55 varieties bred by an accelerated breeding scheme; 27 drought-tolerant and two with enhanced iron and zinc content. Our experience has demonstrated that through the use of more optimized, standardized and collaborative breeding procedures by breeding programs across Africa, it is possible to speed official sweetpotato variety release and contribute to reducing the severe micronutrient deficiencies on the continent.

In Burkina Faso, cassava has been introduced some decades ago.It used to be an adequate solution to household food security during food shortage period in some regions. The fermentation technology incorporated in the population's food habits is increasing cassava production and its utilization as food. This contributes to the development of cassava processing units. Cassava is now cultivated both during rainy season and dry season under irrigation. Several improved varieties are available and adapted to the national agroecological conditions and the processing technology. Attiéké is the most widely consumed cassava-based product in Burkina Faso. Its production contributes in generating incomes especially for women (Diacoumba, 2008). The aim of this study is to establish the origins of cassava varieties grown in Burkina Faso, to evaluate cassava variety knowledge and use, the state of its processing, and its contribution to household food security. | MATERIALS AND METHODSAn investigation was carried out in the main cassava production areas of Burkina Faso. The targeted regions were Center West, Cascades, Boucle du Mouhoun, Hauts Bassins, South West, and Center East.Cassava processing units and cassava producers were both the target of the investigation. About 226 farmers from 57 communities in the selected regions were involved in this investigation for cassava production and use of cassava by the households. The data were collected using a questionnaire by SphinxV5demo software. The questions included knowledge of cassava origin in the locality, cassava varieties used or known, the production level, cassava production challenges and opportunities, it family use, and the knowledge about cassava toxicity. For the industrial uses and cassava processing, another questionnaire was used. Eighteen processing units using cassava roots as raw material and located in Léo, Dédougou, Gaoua, Kampti, Orodara, and Bobo Dioulasso were surveyed. The required questions focused on the processing level and cassava-based products. The collected data were then analyzed with R statistical software for average determination variance and linear regression. The graphics are made with Excel (2010).Food security definition here used is base on the FAO (2012) recommendation of 2300 kcal per adult per day to evaluate the contribution of cassava to household food security. Food security status of households can then be expressed nationally as follows:where F secn = food security status of household n; X n = per capita calorie consumption of household n; Z n = recommended daily minimum energy requirement of 2,300 kcal.The contribution of cassava to family need is evaluated based on equation (3) of household needs: | RESULTS 3

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