Ghrood Al Aswd*⁽¹⁾  Ghassan AL Lahham⁽¹⁾  and Saoud Shehab⁽¹⁾

(1). Crops Researcher Administration, General Commission for Scientific Agricultural Research (GCSAR), Damascus, Syria.

 (*Corresponding author: Dr. Ghrood Al Aswd. E-Mail: ghroodaswd@yahoo.com).

Received: 28/10/ 2015                                     Accepted: 02/12/ 2015

Abstract

The present investigation was conducted at the 1^st May Station in General Commission for Scientific Agricultural Research (GCSAR), Syria, during two successive seasons 2011 and 2012. The main objective was to study both the general (GCA) and specific (SCA) combining abilities and mid and better-parents heterosis of days to flowering, 100 seeds weight, percent of oil, percent of protein and grain yield. Half diallel cross was employed in randomized complete blocks design with four replications. Results revealed the dominance of variances of specific combining ability of yield and 100 seeds weight, indicating the importance of non-additive gene action. Therefore, these traits were affected by the over-dominance gene effect, while the additive gene action was predominant for days to flowering, percent of oil and percent of protein, that means the last three characters were affected by partial-dominance gene effect. The hybrids Sb239×Sb308, Sb235×Sb305, Sb235×Sb298, Sb181×Sb305 and  Sb181×Sb235 showed a positive and significant heterosis values comparing with best parent for grain yield trait. Because of that they are subjected to the over dominance effect, and most of those hybrids owned significant and positive SCA, this is can be attributed to the strong genetic relationship between them, because their effect is related to the existence of dominance.

Keywords: Half- diallel cross, General and specific combining ability, Heterosis, Soybean.

Full paper in Arabic:

السلوكية الوراثية لبعض الصفات الإنتاجية والنوعية لطرز من فول الصويا  [.Glycine max (L.) Merr]