الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 216 |  |  |
| | | from | 216 | | |
Abstract
Objectives : 1- Study the genetic behavior for morphological and floral traits of the parental lines which affectionate by restoring ability. Consequently, the yield of seed set of hybrid rice.2-Study the hybrid vigor (Heterosis) for 24 F1s and estimate the genetic parameters for yield and its components. 3- Study the restoring ability of the pollen parents over different cytoplasmic sources, and detect an important Rf genes in rice by using SSR markers. Methods & Results :1- The experiment comprised hybrid progenies derived from 24 cross combinations generated through Line x Tester mating design.2- Four cytoplasmic male sterile lines (CMS) viz., IR69625A, IR58025A, Pusa 6A and G46A, possessing Wild abortive (WA) type and G46A possessing Gambaica type of cytoplasm were used as female lines. Six divers restorer cultivar viz., Giza178R, Giza182R, GZ5121-5-2R, GZ 6296-12-1-2-1-1, PR2 and PR78 were used as pollen parents (testers).3-The fertility restoration ability for each parent depend on its contains of Rf genes and gene expression in cytoplasmic sources.4-Floral traits for female parents are very important to increase the outcrossing rate in hybrid rice seed production. Conclusion:The parental lines Giza178R, PR2 and PR78 had good restoration ability for CMS lines to produce new hybrid combinations depending on cytoplasmic male sterile source.they had favorable male floral traits that influencing on the ability of restoration. The female line IR69625A, IR58025A and G46A were found to be a good combiners for floral traits under study. These female lines had desirable floral traits that could be utilize in increasing the outcrossing rate to get high seed set in hybrid rice seed production.The restoring ability does not depend only on the restorer genes and number or expression of Rf genes, but also depend on the genetic background of the CMS lines.