Six CMS lines possessing different cyto-sterility sources from O. rufipogon and O. nivara
were evaluated for pollen and spikelet sterility characters in advanced back cross
generations (BCs-BCs). All CMS lines showed 100 per cent spikelet sterility but the
pollen stainability varied depending on the CMS source. The lines viz., RPMS 1~1,
1-2, 1.3, 1-4 and RPMS 2 possessing cyto-sterility source from O. rufipogon and O.
nivara respectively were found to have gametophytic type of male sterility and RPMS
4 possessing g"nivara source was found to exhibit sporophytic male sterility system.
The maintenarti::e of complete male sterility with restorers of WA system indicate the
diversified nature of new male sterility sources. The field evaluation of these new
CMS lines along with CMS lines belonging to wild abortive (WA), O. perennis (IR
64A) and MS 577A sources, carried out during khari! 1994 and rabi 1994-95 seasons
demonstrated that in addition to stable male sterility the new CMS lines possessed
very good panicle and· stigma exsertion rate and high rate of outcrossing which will
goa long way in maximising the seed yield in hybrid rice seed production plots. The
efforts are on to identify effective restorers for the new CMS sources. Reduction in
the cost of hybrid seed and the nuclear and cytoplasmic diversification of hybrids will
help in large scale adoption and sustenance of hybrid rice technology in India
respectively, in the years ahead.
Keywords: Cytoplasmic diversification of male sterility, hybrid rice, inter-specific crosses, pollen sterility
Article DOI: NA
Print ISSN: 0019-5200
Online ISSN: 0975-6906
M. S. RAMESHA, B. C. VIRAKTAMATH, M. ILYAS AHMED AND C. H. M. VUAYAKUMAR info_circle