Author
McCarty, Jack | |
WU, JIXIANG - MISSISSIPPI STATE UNIV | |
Jenkins, Johnie |
Submitted to: Euphytica
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/27/2007 Publication Date: 5/9/2008 Citation: McCarty Jr., J.C., Wu, J., Jenkins, J.N. 2008. Genetic association of cotton yield with its component traits in derived primitive accessions crossed by elite Upland cultivars using the conditional ADAA genetic model. Euphytica. 161:337-352. Interpretive Summary: Boll number, lint percentage, and boll weight are three component traits for lint yield of cotton. Developing high yielding cotton lines depends on the ability to understand the relationship of lint yield with these component traits. Fourteen day-neutral lines with good fiber quality derived from primitive cotton accessions were crossed with five commercial cultivars. The parents and their second generation progeny were grown and evaluated in 1998 and 1999 at Mississippi State, MS. The parents and third generation progeny were evaluated in 2000. Lint yield and the three component traits were analyzed using a conditional based genetic model. Results showed that boll number or boll number with lint percentage or boll weight contributed the majority of the phenotypic variance and genetic variance components for lint yield. Boll number was more important than the other two component traits in terms of contribution to genetic effects. The results further showed that the combination of boll number and boll weight greatly increased the contribution to lint yield compared to boll number alone. The genetic contribution effects were predicted for parents and crosses. Results showed that a balanced selection of boll weight and boll number should be used to obtain high yield cotton lines. Technical Abstract: Boll number, lint percentage, and boll weight are three component traits for lint yield of upland cotton, Gossypium hirsutum L. Selecting high yielding lines or hybrids depends on the ability to dissect the genetic relationship of lint yield with these component traits. In this study, 14 day-neutral lines with desirable fiber quality derived from primitive accessions were top crossed with five commercial cultivars. The F2 populations and their parents were grown in one location in 1998 and two field locations in 1999 at Mississippi State, MS. The F3 populations and parents were grown in two locations in 2000. Lint yield and three component traits were measured and analyzed by the ADAA genetic model with the mixed model based conditional approach. Results showed that boll number or boll number with lint percentage or boll weight contributed the majority of the phenotypic variance and genetic variance components for lint yield. Boll number played a more important role than the other two component traits in terms of additive, dominance, and additive × additive effects. The results further showed that the combination of boll number and boll weight greatly increased the contribution to lint yield even though boll weight itself had no significant contribution to lint yield compared to boll number alone. The genetic contribution effects were also predicted due to single component traits or their combinations for all parents and crosses. The results revealed that balanced selection of boll weight and boll number should be considered for obtaining high yielding hybrids or pure lines. |