Studies on heterosis of some maintainer and restorer lines for cytoplasmic male sterile system in hybrid rice [electronic resource].

Includes references.

This investigation was carried out to evaluate the manifestation of heterosis for eleven agronomic, yield and its components and panicle traits. Five parental lines were utilized to produce 20 hybrids, three of them were maintainer of the CMS lines, Le.lR58025B, IR69625B, IR68886B. The other two parental lines were Egyptian varieties identified as good restorers viz. Giza 178R and Giza 182R.The hybrids were obtained in a complete diallel crosses of five lines evaluated for different traits. The highest heterosis values versus better parent (B.P.)% of 88.3% was regarded for grain yield planr1 followed by panicles planr1 (75.66%) and tillers planr1 (69.38%). The highest mid-parants (M.P.)% heterosis values were observed for the same previous traits, respectively. On the other hand, the highest standard heterosis(S.H.)% of 83.8% was observed for tillers planr1, followed by grain yield planr1 (80.42%) and panicles planr1 (77.83%). Evaluation of hybrids for heterosis breeding based on six considerations, mean performance B.P., M.P. and S.H.%, SCA and GCA effects of female or male parent indicated that out of 20 hybrids studied that Giza 178R x IR68886B, Giza 182R x IR68886B, Giza 182R x Giza 178R and the reciprocal hybrids Giza 178R x Giza 182R and IR68886B x Giza 178R were the most promising ones for grain yield planr1 and most of the studied traits. The combinations involving the restorer lines Giza 178R and Giza 182R and the maintainer line IR68886B were the most promising ones for commercially exploit heterosis.

Summary in Arabic.

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