Estimation of Combining Ability, Dominance Degree and ‎Heterosis in Some Single Crosses of Bread Wheat ‎ ‎(Triticum eastivum L.) ‎

Mohamed Baker AlAbd AlWahed *(1) Ayman Alarfi (2)  and Jalal Abboud(3)

(1). Department of Field crops. Faculty of Agriculture. Al-Furat University, Deir Ez Zoar, Syria.  

(2). Tartus Agricultural Center, General Commission for Scientific Agricultural Research GCSAR. Damascus, Syria.

(*Corresponding author: Eng. Mohamed Baker AlAbd AlWahed. E-Mail:

Received: 16/01/2020                               Accepted: 02/03/2020


This study was carried out in cooperation between Faculty of Agricultural at Al- Furat University, and the General Commission for Scientific Agricultural Research in Izraa Research Station in Syria during 2016/2017 and 2017/2018 seasons. Seven bread wheat (Triticum aestivum L.) genotypes were used viz. Douma 64453, ACSAD 1252, ACSAD 1149, Douma 2, Douma 4, Jawaher14 and Sham6. Half diallel mating method was followed to get 21 hybrids. The hybrids and their parents were sown in the second season, using a randomized complete block design with three replications to estimate general combining ability, specific combining ability, dominance degree, and both mid and better parent heterosis for traits; number of days to heading, plant height, number of spikes per plant, number of grains per spike, biological yield per plant, thousand kernel weight, and grain yield per plant. The results indicated non-additive gene action in all trait inheritance, except number of spikes per plant, which was equally controlled by additive and non-additive genes. Three parents had high general combiners for grain yield, i.e. Douma64453, ACSAD1252 and Jawaher14. Thus, the derived progenies of these parents in the breeding program will have high gene inheritance. Many hybrids with positive specific combining ability were obtained from parents with positive general combining ability, which also have both mid and high parent heterosis, including (Sham6 x Douma64453), (ACSAD1252 x Jawahar14), (Jawahar14 x Douma4) and (Sham6 x ACSAD1149). Thus theses hybrids could be used for selection in segregating generations in order to reach high yielding wheat lines.  

Key words: Bread wheat, Combining ability, Heterosis, Dominance degree.

Full paper in Arabic: PDF