The Role of Genetic Resources in Tuber Crop Improvement

Abstract

Over the years, the Central Tuber Crops Research Institute, Trivandrum
(Kerala) has accumulated 3,250 accessions of diverse genetic resources of tropical
tuber crops. Tbese include cassava (Manihot esculenta), sweet potato (Ipomoea
batatas), yams (Dioscorea esculenta, D. alata, D. rotundata), aroids (Colocasia
esculenta, Xanthosoma sagittifolium, Amorphophallus campanulatus), Coleus (Coleus
parvijiorus), yam been (Pachyrrhizuserosus), winged bean (Psophocarpus tetragonolobus),
arrow root (Maranta arundinacea) etc. The utilisation of this diversity for
identifying promising types is discussed. Critical evaluation of the -germplasm and
grouping of the accessions in various classes based on different morphological and
tuber characters .resulted in the identification and release of a few clones
such as "Sree Lathi/'. "Sree Keerthi", "Sree Roopa", "Sree Priya" and "Sree
Subhra" for general cultivation while a few others formed the basic parental
materials indeveloping superior hybrids in cassava and sweet potato. In cassava,
"M4" which is an introduction from Malayasia, is the most popular cultivar in
Kerala for table purposes