Combining ability estimates for grain yield and its components of yellow maize inbred lines [electronic resource].

Includes references.

Six yellow maize (Zea mays L.) inbred lines were crossed in a half diallel mating scheme at Gemmeiza Agric. Res. Stn. in 2009. In 2010, the resulting 15 crosses along with three check hybrids; SC 162, SC 164 and SC 166 were evaluated at Gemmeiza and Mallawy, where GCA and SCA effects were estimated'; Location and crosses mean squares were significant for all traits except for no. of rows ear-1 .Significant cross x location interaction mean squares were recorded for all traits, except for ear diameter and no. of rows ear-1 . The mean squares associated with GCA and SCA were significant for all traits at both locations and also in the combined analysis, indicating that both additive and non-additive gene effects were involved in the inheritance of the traits. The ratio of GCA/SCA mean squares exceeded the unity for no. of rows ear-1 and no. of kernels row-1 at the two locations, and their combir.ied analysis. However, the same ratio was less than unity for ear diameter, 100-kernel weight and grain yielq fed.-1 at the two locations and their combined analysis, indicating that additive (a) and (aa) gene effects play an important role in the inheritance of the traits in the first case and non-additive was predominant in the second one. The ratio of GCA x L/SCA x L mean squares was less than unity for ear diameter, 100-kwt and grain yield fed.-1 , indicating that nonadditive genes were more interacted with location than additive ones for the traits in question, while the same ratio exceeded the unity for no. of rows ear-1 and no. of kernels row-1 , indicating that additive (a) and (aa) changed with changing the environments. The parental genotype (P2) was a good general combiner for no. of kernels row-1 and 100- kwt at Gemmeiza, while P4 was cpnsidered as a good general combiner for no. of rows ea(1 and 100-kernel weight at Mallawy and for no. of kernels row-1 at Gemmeiza. The same parental genotype performed as a good general combiner for ear diameter, no. of rows ea(1 and grain yield fed.-1 at Mallawy. The crosses; Pl x P3 and PS x P6 had significant inter- and intra-allelic interactions for ear diameter at both locations and their combined data, no. of kernels row-1 at Gemmeiza and combined data and grain yield fed.-1 at Mallawy. Moreover, the crosses; Pl x P2 , P2 x P4, P3 x P6 and PS x P6 surpassed the three check hybrids with respect to grain yield. Keywords: (Zea mays L.), GCA, SCA, gene effect, Diallel cross.

Summary in Arabic.

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