Diallel analysis among new yellow maize inbred lines for grain yield and other agronomic traits

Abstract

Yellow maize (Zea mays L.) is one of the important sources of animal feed in Egypt. The national maize programmes uses conventional crop breeding methodology, which depends on the development inbred lines of maize from open pollinated varieties or other heterogeneous sources. The objective of this study was to assess the general and specific combining ability for nine yellow maize inbred lines and their crosses for grain yield and other morphological traits, under Egyptian conditions. Nine new yellow maize inbred lines, derived from different yellow maize sources, were crossed in a half diallel mating scheme in 2020 summer season, at Gemmeiza Agricultural Research Station Gharbia Governorate in Egypt. The resulting 36 crosses, along with two commercial check hybrids (SC 168 and Pioneer SC 3444), were evaluated at three locations, i.e. Gemmeiza, Mallawy and Sids Agricultural Research Stations of the Agricultural Research Center (ARC), in 2021 summer season in Egypt. Overall, the additive gene effects played a major role in the inheritance of days to 50% silking, plant and ear heights; while the non-additive gene effects were mostly responsible for controlling the inheritance of grain yield. The parental inbred lines (P1 and P2) possessed significant (P<0.05) negative estimates of GCA effects for days to 50% silking towards earliness. The best general combiners were inbred lines P2 and P6 for plant and ear height, and these inbred lines would be good combiners for breeding to short hybrids and low ear placement. Crosses (P1xP9 and P3xP4) had desirable SCA effects and significantly out-yielded the two checks.