Combining ability and heterosis for earliness characters in line×tester population of Gossypium hirsutum L.

Abstract

The objective of this study was to estimate the general combining ability of the parents and specific combining ability of hybrids for earliness traits for line selection. Inheritance and interrelationships of earliness characters were evaluated in a line x tester design. Three intermediate-early-maturing female (lines) which are grown regionally and four early-maturing males (testers) cotton varieties were crossed in 2003. The twelve F(1) and seven parents were planted randomized block design with three replications in 2004. For each earliness trait, general combining ability (GCA) and specific combining ability and gene effects were estimated using the line x tester method of analysis and also were determined heterosis and narrow sense heritability. Parents and their hybrids (except the monopodial branch) were significant for all the earliness traits studied. Estimates of variance due to GCA and SCA and their ratio revealed predominantly non-additive gene effects for date of first square, date of first flowers and harvested rate of first picking. Among the lines, Ersan 92 and Maras 92 and among the testers Acala Royal was found to be the best general combiners for most of the earliness characters. Four out of twelve crosses namely Ersan 92 x Chirpan 603, Ersan 92 x Acala Maxa, Maras 92 x Acala Royal and Nazilli 87 x Acala Royal were found to be the best crosses for investigated earliness characters.

Combining ability for fiber quality parameters and within-boll yield components in intraspecific and interspecific cotton populations

“…Significant differences were detected among parents and hybrids in both fiber quality parameters and the line × tester analysis method has been widely used in self-and cross-pollinated plants by plant breeders (Konak et al, 1999;Mert et al, 2003;Ahuja and Dhayal, 2007;Basbag et al, 2007). Sprague and Tatum (1942) used the term "general combining ability" (GCA) to designate the average performance of a line in hybrid combinations, and they used the term "specific combining ability" (SCA) to define those cases in which certain combinations perform relatively better or worse than expected on the basis of the average performance of the lines involved.…”

Combining ability and character association of agronomic and biochemical traits in pea (Pisum sativum L.)

“…Among the different breeding tools, the line × tester analysis is used in both self as well as cross-pollinated crops to estimate general and specific combining abilities of specific traits and to determine favourable parents and crosses (Kempthorne, 1957). Combining ability analysis is an important tool for the selection of desirable parents together with the information regarding nature and magnitude of gene effects controlling quantitative traits (Basbag et al, 2007). Assessment of combining ability has been undertaken in some legume crops such as soybean (Mebrahtu and Devine, 2009); pigeonpea (Singh and Singh, 2009); pea (Narayan et al, 1998;Dhillon et al, 2006;Singh et al, 2007;Sharma et al, 2007;Ceyhan, 2003;Ceyhan et al, 2008).…”

High-density linkage map construction and QTL analysis for earliness-related traits in Gossypium hirsutum L

“…In terms of plant development, earliness may be described in reference to budding date, flowering timing (FT) and the whole growth period (WGP) [4]. Other agronomic traits, such as plant height (PH), node of the first fruiting branch (NFFB) and height of the NFFB (HNFFB), have also been used as earliness indexes [5, 6]. For example, Godoy and Palomo concluded that the lower the NFFB and the shorter the PH, the earlier the maturity [5].…”