By: Libby Arcia
Published: 2017-12-04

Adapted from a video produced by ECHO in 1993 featuring Dr. Frank Martin (1928 – 2014). Revised by ECHO staff in 2015.

Dr. Martin Price, co-founder of ECHO, first met Dr. Frank Martin when the latter was director of the US Department of Agriculture’s Research Station in Mayaguez, Puerto Rico. When Dr. Price began at ECHO, one of the first things he did was to buy a plane ticket to visit Dr. Martin in Puerto Rico. 

Dr. Frank Martin is best known for his research on sweet potato and other tropical root crops, but his knowledge is much broader than that. He has written on many topics, both for ECHO and for numerous technical refereed journals in the scientific community. 

Tropical root and tuber crops are a valuable option for producing food under challenging growing conditions. This document aims to familiarize readers with their strengths and weaknesses under different tropical environments. 

Based on their use, edible plants are classified as:TN 81 Thumbnail

Cereal grains - include wheat, rice, and corn. They contribute energy in the form of carbohydrates, and are a good source of B vitamins. 

Grain legumes produce edible seeds, including beans and soybeans. They are high in protein content. Grain legumes can be a good source of protein in place of meat. 

Vegetables / Edible leaves are the most abundant in the tropics. Leafy vegetables are a source of diverse nutrients, vitamins A and C, protein, and minerals. 

Roots and tubers are classified as vegetables and considered a “poor man’s crops” by many. They mainly contribute carbohydrates, starches and some sugars to the diet, but they all contain other nutrients. The leaves of some of these crops are edible and provide protein, minerals and vitamins (Hahn 1984).

Out of thousands of existing tubers, only about 25 species are considered of primary importance. Examples include potato, sweet potato, cassava, yams and aroids. The significance of these varies between regions. Cassava, for example, only provides 1.6% of the world’s plant-based calories; however, it accounts for over half of plant-derived calories in Central Africa (FAO 1998). Each of these five aforementioned important root and tuber crops are discussed in the complete article which provides information on life cycles, propagation and storage, leaf usage, and food processing.  This summary presents a brief outline of a few roots and tubers. 

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