(introduction...)

181. Up to now in this booklet, we have learned about cassava. Let us now study sweet potatoes. We will learn about the feed value of sweet potato tubers and how to process them.

182. Sweet potato tubers are starchy like cassava roots.

183. Sweet potatoes are an important source of food in Asia and the Pacific. They are a major crop in China, the Philippines, Papua New Guinea and Pacific Islands.

184. More than 90 percent of world sweet potato production comes from Asia. China is the world's largest producer. It produces over 80 percent of world production.

185. Sweet potato is a creeping plant. It is a perennial and can grow for several years.

186. But it is cultivated now mainly as an annual crop.

187. The herbaceous stem of the sweet potato plant is called the vine. The vines are thin and trailing.

188. Some sweet potato cultivars grow like a bush. Some cultivars have vines of medium length. Others have long vines.

189. The size and shape of the leaves also vary widely among different cultivars. At least 15 different leaf types are known.

Leaves

190. Sweet potato tubers differ greatly in shape, colour of skin and colour of flesh.

191. Tubers may be round or elongated. The colour of the skin can be white, yellow, orange, red, purple or brown. The colour of the flesh can be white, yellow, orange, reddish or purple.