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.

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Objective: To assess the school food environment in terms of breakfast consumption, school meals, learners' lunch box, school vending and classroom activities related to nutrition. Design: Cross-sectional survey. Setting: Ninety purposively selected poorly resourced schools in South Africa. Subjects: Questionnaires were completed by school principals (n 85), school feeding coordinators (n 77), food handlers (n 84), educators (n 687), randomly selected grade 5 to 7 learners (n 2547) and a convenience sample of parents (n 731). The school menu (n 75), meal served on the survey day, and foods at tuck shops and food vendors (n 74) were recorded. Results: Twenty-two per cent of learners had not eaten breakfast; 24 % brought a lunch box, mostly with bread. Vegetables (61 %) were more often on the school menu than fruit (28 %) and were served in 41 % of schools on the survey day compared with 4 % serving fruit. Fifty-seven per cent of learners brought money to school. Parents advised learners to buy fruit (37 %) and healthy foods (23 %). Tuck shops and vendors sold mostly unhealthy foods. Lack of money/poverty (74 %) and high food prices (68 %) were major challenges for healthy eating. Most (83 %) educators showed interest in nutrition, but only 15 % had received training in nutrition. Eighty-one per cent of educators taught nutrition as part of school subjects. Conclusions: The school food environment has large scope for improvement towards promoting healthy eating. This includes increasing access to vegetables and fruit, encouraging learners to carry a healthy lunch box, and regulating foods sold through tuck shops and food vendors. Keywords School food vendorsSchool tuck shop Lunch box School feeding South AfricaSouth Africa experiences the double burden of undernutrition and overweight. A national survey showed that 20?7 % of 1-to 9-year-old children were stunted, 8?1 % were underweight, 5?8 % were wasted, and 14?0 % were either overweight or obese (1) . Overweight/obesity increases progressively as children become older (2) , and the second national youth risk behaviour survey showed that 20 % of secondary-school learners were overweight and 5 % were obese (3) . Overweight/obesity is even more prevalent during adulthood and, in 2003, 54?9 % of adult women and 29?8 % of adult men were either overweight or obese (4) .

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