Combining Ability for Some Earliness Indicators in Cotton Hybrids (Gossypium hirsutum L.)


                                 Ahmad Al Jouma(1) and Jamila Dirbas*(1)


 (1)- Cotton Research Administration, Aleppo, Syria.  

 (*Corrsponding author: Jamila Dirbas. E-Mail:

Received: 10/05/2020                                Accepted: 23/06/2020


The experiment was conducted at Hama Center for Scientific Agricultural Research during 2018 and 2019 seasons according to randomized complete block design with three replication. This research objected to study combining ability for earliness indicators of F1 hybrids resulted from half diallel program of twelve parents of upland cotton. Analysis of variance referred to significant differences among the genotypes for all characters. The percentages of δ2GCA/δ2SCA were more than one for all traits except node number to first sympodia brunch that indicated to addictive gene effect, whereas non addictive gene controlled to inheritance of node number to first sympodia. Parent Aleppo 124 was the best general combiner to days to first flowering and days to first boll (-4.51*) (-7.98*) respectively, while, parent Aleppo 118 to node number to first sympodia (-0.58*) and parent Fantum to earliness %. Subsequently, it can be entered to breeding programs for improvement of these traits. Hybrid (Millinium x Cherpan 432) had the best SCA for days to first flowering (-5.37*), hybrid (Fantum x Lider) days to first boll (-8.64*) and hybrid (Millinium x Lider) to earliness % (32.78*) therefor, it can be used in breeding programs for exploiting hybrid vigor. Hybrids had non-significant SCA that resulted from general combiner parents can be used to get distinct genetic combinations at late segregating generations.

Keyword:  cotton, combining ability, earliness, half diallel.

Full paper in Arabic: PDF