Almost all the sorghum [Sorghum bicolor (L.) Moench]
hybrids commercially exploited to date are based on A1
CMS (cytoplasmic-nuclear male-sterility) system. For
genetic diversification and to produce more heterotic
hybrids, all the available CMS systems are to be studied
for genetics of male-fertility restoration preferably in isonuclear backgrounds. The A1, A2, A3 and A4(M) cytoplasms
present in three different nuclear backgrounds were
crossed with two common restorers. The segregation of
fertile and sterile plants observed in F2 and BC1
populations during rainy and post-rainy seasons of 2007
was tested with χ2 for goodness of fit for monogenic,
digenic and trigenic ratios. The fertility restoration of A1
CMS system was governed by one basic gene and two
duplicate complimentary genes (45F:19S in F2) all acting
in dominant fashion while the fertility restoration of A2
and A3 CMS systems was governed by three genes where
all of the three complimentary genes in dominant condition
restore fertility (27F:37S in F2). The fertility restoration in
A
4(M) CMS system was governed by three genes where
any two of the three dominant duplicate-complimentary
genes restored fertility (54F:10S in F2) in post-rainy season
while two complementary genes in dominant state
restored fertility (9F:7S in F2) in rainy season in the
absence of expression of the third gene.
Keywords: Sorghum, Cytoplasmic-nuclear malesterility, fertility restoration, gene action
Year: 2010
Volume: 70
Issue: 3
Article DOI: N/A
Print ISSN: 0019-5200
Online ISSN: 0975-6906
P. Sanjana Reddy, V. S. Belum Reddy and A. Ashok Kumar info_circle
D. Manohar Rao info_circle