Determination of gene effects and variances in three bread wheat crosses [electronic resource].

Includes reference.

The present work was carried out at Etay-Elbarouri Research Station during four seasons from 2003 / 2004 to 2006/2007. Three crosses among six parents, namely Sills 1 x Genuniza 7, Sakha 93 x Dophin 2 and Gemmiza 9 x Giza 168 were used. Five populations (PI, P2, F, F. and F3) for each cross were used in this investigation.Significant positive heterotic effects were found for all characters, except for number of spikes plant in the second and third crosses and number of kernels spike’ in the first and third crosses. Overdorninanee above the higher parent was detected for all characters, except for number of kernels spike-1M the first eross.The other types of dominance were olso studied. Inbreeding depression estimates were found to be significant and positive for number of spikes planfl,number of kernels spike’ and grain yield plant” in all crosses. Additive gene effects were positive and significant for number of spikes plant’, of kernels spike’, and grain yield plant-1 in the third cross. While, significant negative additive effects were obtained for number of spikes plant 3, number of kernels spikel, grain yield plantl in the second cross and 100-kemerk; weight in the first and second crosses. Do minance gene effects were found to be significant for all characters in all crosses, except the second cross for both number of spikes plant-1’ and grain yield plant-1’ and number of kernels spike-1 in the first cross. Significant positive (E,) were found for 100-kernel weight in the first and theird crosses. Moreover (Fe) were found to be positive and significant for 100-kernel weight in the second and third crosses. High heritability estimates, in broad sense, were detected for all the studied characters, except number of spikes plant-1 --cond cross. Narrow sense heritability estimates ranged from 33.82% for number of sputcs pianfl to 82.20% for 100-kernel weight in the second cross. The parent-offspring regression heritability estimates ranged from 54.14% for number of spikes plant-1 in the second cross to 88.68% for grain yield plant’ in the first cross, The expected and actual genetic advance were moderate for 100- Kernel weight and high for grain yield plant-1 in all crosses Key words: Bread Wheat, Heterosis, Inbreeding GeneAction.

Summary in Arabic.

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