ISHS Acta Horticulturae 380: Symposium on Tropical Root Crops in a Developping Economy
THE ROLE OF THE WILD IPOMOEA TRIFIDA GERMPLASM IN SWEET POTATO BREEDING |
| Authors: | I. Shiotani, Z.Z. Huang, S. Sakamoto, T. Miyazaki |
| Abstract:
The species Ipomoea trifida (HBK) Don. is a wild progenitor of the sweet potato. Although the cultivated sweet potato is exclusively hexaploid (2n = 90), the species I. trifida contains different cytotypes such as diploids (2n = 30), tetraploids (2n = 60), and hexaploids (2n = 90). First, some ecological features of this species are presented to show its genetic diversity and potentials as gene sources. After the interspecific hybridization and subsequent introgression, high-starch varieties have been developed and many high-starch selections have been used to form a family from a cross of the Pelican Processor x 6x trifida strain (K123–11). Second, we discuss the possible genetic effects of the wild material on the starch yields of these derivatives. The sweet potato as well as trifida polyploids are essentially autopolyploids with the genome of the basic 2x trifida. The autoploidy structure is of great advantage for the use of lower ploid trifida materials through intra- and inter-ploidy hybridization in sweet potato improvement. Third, we report such breeding schemes along with their procedures and recent experimental results. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
