Oguz Bilgin, Kayihan Z. Korkut, Alpay Balkan, and Ismet Baser*
The present study was conducted to evaluate magnitude of heterotic effects in F1 hybrids of seven durum wheat cultivars, and to investigate the performance and relationship of F1 hybrids and parents for the spike characters and to select suitable parents and population for designing an effective wheat breeding programme. Highly significant genetic variability was present in parents and their genetic combinations for the characters. The degree and direction of heterosis varied for different characters and for different hybrids. The highest heterosis over mid and better parents (120.14-109.93%) was recorded in hybrid of Kyzyltan91xIDSN209 for grain weight/spike. Maximum limits of heterosis over mid and better parent for spike length, spikelets/spike, grains/spike, spike density, grains/spikelets and spike harvest index were 8.77-8.14 (Svevo//GedxYav), 8.37-7.37 (Svevo//GedxYav), 74.71-57.06 (Kyzyltan91xZenit), 19.41-10.55 (Kyzyltan91//GedxYav), 72.41-57.23 (Kyzyltan91xIDSN209) and 23.29-18.74% (Kyzyltan91xIDSN 209), respectively. Kyzyltan91, Svevo and IDSN209 should be utilized to improve spike characters in the hybridization scheme, and the hybrids Kyzyltan91xIDSN261, Kyzyltan91xSvevo, Kyzyltan91xIDSN209, SvevoxZenit and Kyzyltan91xSvevo must be considered for finding out transgressive segregants in late segregations to develop a potential durum wheat variety.