Abstract:
Gadam cultivar of sorghum has been characterized by low yields compared to the international yield levels
of sorghum. In this research, Gadam was crossed with Serena, Seredo, and Kari/Mtama-1 in an attempt to
increase yield through heterosis. The objective of this study was to determine the level of compatibility and
heterosis in crosses between Gadam and the three sorghum lines in a reciprocal crossing. Gadam was
crossed with the three lines and their reciprocals to make six treatments that were subjected to compatibility
and heterosis tests. The F1 hybrid lines and their parental controls were sown in a randomized complete
block design in three replicates. Compatibility and heterosis data variances were analyzed using R
statistical software. The cross between Gadam x Serena, Serena x Gadam and the parent Gadam exhibited
moderate mean plant height ranging from 99.5 cm to 120.5 cm. The cross Gadam x Serena recorded a
desirable negative mid-parent heterosis of -19.89 and -16.16 for plant height and days to maturity
respectively. All F1 hybrids recorded positive mid-parent heterosis for the panicle length, the number of
reproductive tillers, a thousand seed weight, and the number of tillers per plant. The crosses Gadam x
Seredo, Seredo x Gadam, Gadam x Serena and Kari/Mtama-1 x Gadam recorded significantly lower grain
filling percentages compared to their parents. In conclusion, the F1 hybrids differed significantly from their
reciprocal crosses especially in days of heading, flowering, and maturity indicating a significant maternal
influence in these traits. Also, the mid-parent and better parent heterosis had a nonsignificant difference in
quantitative traits assessed except for the plant height and grain filling percentage.
