Abstract:
The yam is an economic tuber crop utilized for food, feed, and various industrial applications. Botanical seed viability, seedling growth, and development are among factors that influence
plant population dynamics, development, structure, and sustainability. However, little is known
about seed viability, growth, and yield potential of seed-progenies developed using different mating
designs. This study assessed seed germination, seedling growth, and yield traits in seed-progenies
developed using North Carolina I (NC-1) and polycross mating designs. For this, seed germination
and seedling nursery trials established using seed-progenies from different yam crosses were used.
Results revealed that days to first seed germination (DAYFG), days to 50% germination (DAYSG),
coefficient of velocity of germination, seed emergence speed (SES), germination index, final germina tion percent, and seedling vigor index significantly (p < 0.05) varied within and among NC-1 and
PC-derived families. The mean days to first seed germination (DFSG) and DAYSG seed-progenies of
NC-1 were significantly lower than the polycross progenies. Moreover, the seedling-progenies from
the polycross produced a higher number of stems and more elongate tubers than those originated
from the NC-1 mating. Progenies of family TDr1687 from a polycross mating were among the
families that had the highest stem number (2.2), longest tuber (7.5 cm), and widest tuber (2.8 cm).
The inter-family means of both NC-1 and polycross had a non-significant variation for mean tuber
weight per plant. Our results suggest the relevance of seed germination and seedling attributes for
selection of superior progenies at the early generation stage trials in yam breeding.
