الفهرس | Only 14 pages are availabe for public view |
Abstract The present investigation was carried out at El-Mattana Agric. Res. Station, Agric. Res. Center, Egypt, during the three successive seasons of 2000/2001, 2001/2002 and 2002/2003. The objective of the present investigation were to estimate mean performance, heterosis, general and specific combining abilities, as well as, correlations between different traits. The materials used in the this study were 7 durum wheat varieties (Triticum turgidum var. durum) differed widely in their genetic background and origin, i.e. Kucuk, Rascn/Kitti, Yavaros-79 (Bani Sweif 1), Terbol 97-4, Waha, Sohag 2 and Sohag 3. Parental genotypes, F1 hybrids and F2 populations were grown in a complete randomized block design with three replicates. The results obtained from this study are summarized in the following: 1- Mean performance: [1] Days to heading: Significant differences were observed among all studied genotypes the F1 crosses were later or intermediate in spike emergence between the respective parents, except three crosses which possessed the same values of its parents. On the other F2 crosses were earlier or intermediate in spike emergence between the respective parents except two crosses which were later than the respective parents and three crosses possessed the same values of its parents. [2] Days to maturity: most of F1 crosses were later than its respective parents, while most of F2 populations were intermediate or later in values of days to maturity between the respective parents. [3] Flag leaf area: wide variation was observed among all genotypes under study for flag leaf area. Some of F1 crosses were higher than their respective parents, whereas eleven of crosses of F2 populations were intermediate while the other genotypes were lower and/or higher than their respective parents. [4] Plant height: all F1 crosses were either taller or intermediate in height comparing with their respective parents. The same trend with some modifications was found in F2 populations, except two crosses (Kucuk x Waha) and (Waha x Sohag-3) which were shorter in height compared to the respective parents. [5] Number of spikes/plant: All F1 crosses were either higher and/or intermediate in number of spikes/plant comparing with their respective parents. Except three crosses which produce fewer tillers than its respective parents and one crosse gave the same values of one of its parents. whereas eleven of F2 populations were higher, seven population were intermediate and three crosses only were fewer in tillers than their respective parents. [6] Number of kernels/spike: Wide variation was observed among all studied genotypes. All F1 crosses were either intermediate and/or higher in values of kernels per spike comparing with their respective parents except five crosses showed lower number of kernels per spike compare to the respective parents, whereas all F2 crosses were 76 lower or intermediate in number of kernels per spike, except one cross only (Yavaros-79 x Waha) was higher than its respective parents. [7] Biological yield per plant: significant differences were observed among all parental lines, as well as, among F1 crosses and F2 populations. For F1 crosses 8 were higher, 10 were intermediate and 3 crosses were lower in values of biological yield/plant. With respect to F2 populations 8 crosses were higher, 7 were intermediate and 7 crosses were lower than their respective parents. [8] Grain yield/plant: significant difference were observed among all parental lines, as well as, among F1 crosses and F2 populations. For F1 crosses: 9 were higher, 8 intermediate and 4 crosses were lower in values of grain yield/plant. With respect to F2 populations: 8 crosses were higher, 8 were intermediate and 5 crosses were lower than their respective parents. [9] Harvest index: nine crosses of F1 crosses and ten of F2 populations exceeded their respective parents in values of harvest index, whereas the other genotypes were intermediate or lower than their respective parents. [10] 100-kernel weight: mean performance of the parental lines, F1 crosses and F2 populations were differed significantly in 100- kernel weight most of F1 crosses, as well as, F2 populations showed higher values of 100-kernel weight than respective parents. |