عنوان المقالة: Development of New Iso-Cytoplasmic Rice-Restorer Lines and New Rice Hybrids with Superior Grain Yield and Grain-Quality Characteristics by Utilizing Restorers’ Fertility Genes
This research was carried out at the Experimental Farm of Sakha Agricultural Research
Station, Sakha, Kafr El-Sheikh, Egypt, during the 2018–2020 rice-growing seasons to develop and
evaluate four iso-cytoplasmic rice-restorer lines: NRL79, NRL80, NRL81, and NRL82, as well as
Giza 178, with ten new hybrids in order to estimate genotypic coefficient, phenotypic coefficient,
heritability in a broad sense, and advantage over Giza 178 as a check variety (control) of new restorer
lines. This study also estimated combining ability, gene action, better-parent heterosis (BP),
mid-parent heterosis (MP), and standard heterosis (SH) over Egyptian Hybrid 1 (IR69A × Giza 178)
as a check hybrid (control) for grain yield, agronomic traits, and some grain-quality characters in
restorer lines and hybrids. The percentage of advantage over commercial-variety Giza 178 (check)
was significant, and highly significant among the newly developed restorer fertility lines for all the
studied traits. This indicates that the selection is a highly effective factor in improving these traits.
New restorer fertility lines showed highly significant positive values over commercial restorer for
grain yield; the values ranged from 51% for NRL80 to 100.4% for NRL82, respectively. Meanwhile,
in regard to the grain shape of paddy rice, three lines of the promising lines showed highly significant
negative desirable values compared with Giza 178; the values ranged from −7.7% for the NRL80
to −15.2% for NRL79, respectively. Based on the superiority of the new lines, the new lines can be
used as new restorer fertility lines to breed promising new hybrids and new inbred rice lines or
varieties. From the results of the testcross experiment, the four promising lines were identified as
effective restorer fertility lines for two cytoplasmic male sterile (CMS) lines. Moreover, the six rice
hybrids showed values for SH heterosis of grain yield/plant of more than 15% over the check hybrid
variety, with high values of 1000-grain weight and desirable grain shape; these hybrids were G46A
× NRL81 (125.1%), G46A × NRL80 (66.9%), IR69A × NRL79 (47.2%), G46A × NRL79 (24.6%), IR69A
× NRL81 (23.4%), and IR69A × NRL82 (16.2%).
Publication Date
5/1/2022
Volume No
Issue No
DOI
https://doi.org/10.3390/genes13050808
Keywords
newly developed restorer lines; grain yield; yield components; heterosis; combining ability; Oryza sativa L.
محمد عبدالحميد عابدين | MOHAMED ABD ELHAMEID ABDEIN | 4463