Abstract:

Pearl millet is a dual-purpose crop in semi-arid zones of Uganda. However, no studies have been conducted to
determine the gene effects for yield and yield-related traits and rust resistance in these environments; yet this
knowledge is important in improving grain yield and rust resistance. A North Carolina II mating design was
adopted to study the genetic effects for rust resistance and yield-related traits of improved pearl millet genotypes.
The experimental design to study the objectives was alpha in two [locations, seasons and replications]. A higher
proportion of general combining ability (GCA) effect was observed for grain yield, days to 50% flowering, days
to 50% anthesis, flower-anthesis interval, days to 50% physiological maturity, plant height, total tiller number,
number of productive tillers, percentage of productive tillers, panicle area, leaf area, 1000-grain weight,
biological yield and harvest index. The specific combining ability (SCA) effect was predominant for area under
disease progress curve. Eleven hybrids performed better than the best male parent and five crosses performed
better than the best female parent for grain yield while all the fifteen selected best crosses performed better than
all parents for area under disease progress curve. Ten crosses were more resistant to rust than the best male
parent and all the crosses were more resistant to rust than the female parents. The additive gene action was
predominant for grain yield, rust severity at 50% physiological maturity, days to 50% flowering, days to 50%
anthesis, total tiller number, percentage of productive tillers, panicle area, 1000-grain weight, biological yield,
harvest index and leaf area. High better-parent heterosis was also observed for most traits including grain yield
and rust resistance. The traits were also characterized by relatively low levels of narrow sense heritability.