Yam Breeding in Ghana

Abstract

CSIR-Crops Research Institute of Ghana is the National Centre of Specialization (NCOs) for Root and Tuber Crops and migrating into a Regional Centre of Excellence (RCOE) in Root and Tuber research in the West African sub-region. Yam is one of the major root and tuber crops of importance in the sub-region and for that matter the NCOS. Even though yams are indigenous to the West African sub-region, with the exception of Dioscorea alata (Asiatic origin), yams are often aptly described as an orphan crop due to the relatively little research effort compared to its significance in the sub-region in particular and the world at large. Breeding of yams therefore can be a challenge due to little literature available on the subject matter. This paper looks at the historic perspective, what can be done presently and projects into future direction of yam breeding in Ghana and the world at large. It also serves as a guide for yam breeding in particular and root and tuber crops in general.

Floral Biology and Pollination Efficiency in Yam (Dioscorea spp.)

“…The mating design in plant breeding refers to a schematic system of crossing to create variability from which transgressive segregants are selected to make new cultivars. In yam breeding, both unsupervised (open-pollinated incomplete pedigree where only one parent is known) and supervised (complete pedigree with both parents known) mating designs are used [69,70]. Unsupervised mating is often achieved with natural open pollination using polycross blocks.…”

“…Based on the experience, IITA yam breeding team uses 1 m × 1 m as the optimal distance between a male and a female parent for insect pollination. Although easy and cheap, the open pollination makes some genetic analyses (specific combining ability, broad and narrow sense heritability) difficult as the male parent of a cross is not often known [69]. Its success is also uncertain for species with asynchronous flowering.…”

“…Thus, it facilitates all genetic analyses such as the estimation of narrow-sense heritability, general and specific combining abilities, additive and non-additive variances, etc. [69]. However, the tiny size of flowers, asynchrony in flowering, incompatibility among parents and the relatively short life of pollen (4-5 h) are challenges for the bi-parental mating design.…”

The National Significance of a DNA Revolution: A Call for Policy Action towards Sustainable Development Goals (SDGs)

“…In the roots and tubers development sector, technologies such as TILLING (Targeting Induced Local Lesions in Genomes), zinc finger nuclease mediated mutagenesis and meganucleases have been experimentally used to obtain improved cultivars through targeted mutations [72]. Full-scale adoption and incorporation of these techniques would result in very desirable roots and tubers, especially in the wake of debilitating yields of cereals which are the most consumed food types.…”