The review was commissioned by CGIAR Research Program on Roots, Tubers and Bananas (RTB).

Key findings of this study note that as food systems in developing countries continue to evolve in response to demographic, economic and environmental pressures, total production of roots, tubers, bananas and plantains (RTBs) surged to 841 million metric tonnes (t) in 2016–18 up from 244 million t in 1961–63). Growth in output of RTBs was particularly strong in Africa increasing from 59 million t in 1961–63 to 351 million t 2016–18. Two-thirds of that increase consisted of cassava and yam with cassava alone accounting for 138 million t or nearly half. Perhaps even more noteworthy, 220 million t of that increase in Africa came since 1988-90 as sweetpotato and potato also recorded noteworthy increases as many countries experienced continued rapid population growth along with the increased importance of urban consumption centers. At the same time, local agri-food systems came under additional stress due to droughts, humanitarian crises, or spikes in commodity prices for food imports.

In Asia, output of RTBs swelled from 135 million to over 395 million t as potato production surged by 160 million t during the last six decades and banana by 56 million t with the region becoming the center of global production for these two commodities as well as sweetpotato as a result. Strong demand for more vegetables and fruit, reflecting consumers’ desire to diversify their diets, drove these increases. Cassava expanded by 64 million t. The bulk (70%) of that increase was concentrated in South-East Asia where booming exports of processed cassava products such as starch catalysed strong productivity growth.

Trends were more uneven and on a much more modest scale in Latin America and the Caribbean as banana and potato expanded by 19 and 23 million t from 1961-63 and 2016-18, while cassava, plantain and sweetpotato grew more modestly, pockets of sharp increases in output for these crops took place in and within specific countries as local food system came under increasing stress due to deforestation, erratic rainfall and natural disasters.

Accompanying these noteworthy trends, producers of RTBs became increasingly market-oriented with sales for cash taking on growing importance to complement their more traditional role as food security crops. In the process, based on estimated farm-gate prices and FAO production data for 2016–2018, potato, cassava, sweetpotato, yam, bananas and plantain had an average annualized economic value of production of US$ 339 billion. As a result, the rise in importance of RTBs in developing country food systems is expected to continue thereby surpassing recent estimates of production of RTBs in 2030. The combined set of findings point to the need for continued support for research on these commodities complemented by the implementation of proven policy measures and collaboration between the private and public sector to ensure achievement of their full potential.