Morphologic identification of duplicates in collections of Ipomoea batatas

Huaman, Z. 1992. Morphologic identification of duplicates in collections of Ipomoea batatas. CIP Research Guide 36. International Potato Center, Lima, Peru. 28 p.

Duplicates in sweet potato collections are samples of the same cultivar that were collected in different farms of one or more localities. Their presence increases the cost of maintenance of these collections and slow down the process of evaluation for desirable traits for use in breeding. In many countries, there are several collections maintained by · universities, experiment stations or private farmers. When a national sweet potato collection is organized, it is recommended: l. To introduce all those collections in one site to grow them under the same environment. 2. To record some of their key morphologic characters to facilitate their grouping according to similarities in their vine, leaf and storage root characters. 3. To organize a new planting of the collection according to these groupings, and to make more detailed morphological comparisons between those accessions that are morphologically alike. The identification of duplicates in sweet potato collections depends on the degree of accuracy with which the data were obtained during the morphological characterization in the field; on the correct transfer of the data to a file for computer processing; and on a good validation of the data once the accessions of the collection are grouped according to their similarities.