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of recurrent parent genome in a backcross breed-
ing program. With the development and access
to reliable PCR-based allele-specific markers
such as simple sequence repeats (SSRs) and sin-
gle nucleotide polymorphisms (SNPs), MAS is
becoming an attractive option, particularly for
oligogenic traits such as QPM (Babu et al. 2004).
A rapid line conversion strategy for QPM has
been developed (Babu et al. 2005) consisting of a
two-generation backcross program that employs
foreground selection for the
o2
gene in both
backcross (BC) generations, background selec-
tion at non-target loci in the BC
2
generation, and
phenotypic selection for kernel modification and
other desirable agronomic traits in two subse-
quent selfed generations. This brings together
the salient features of both marker-aided and
phenotypic-based selection approaches, such as
fixing the large segregating generation for the
target allele (
o2
), reducing the linkage drag by
selection of flanking markers for recipient allele
type, recovering the maximum amount of the
recurrent parent genome within two BC genera-
tions, and providing scope for precise phenotypic
selection for desirable agronomic and biochem-
ical traits on a reduced number of progeny.
There are a few successful examples of MAS
for maize improvement using
o2
-specific molec-
ular markers (Babu et al. 2005; Gupta et al.
2009; Prasanna et al. 2010). The parental lines
of 'Vivek Hybrid 9' (CM145 and CM212) devel-
oped at Vivekananda Institute of Hill Agricul-
ture (VPKAS), Almora, India, were converted
into QPM versions through transfer of the
o2
gene using MAS and phenotypic screening for
endosperm modifiers. The MAS-derived QPM
hybrid 'Vivek QPM 9' was released in the year
2008 for commercial cultivation in zones I and
IV in India. Vivek QPM 9 shows a 41% increase
in tryptophan, 30% in lysine, 23% in histi-
dine, and 3.4% in methionine, coupled with a
12% reduction in leucine, as compared to Vivek
Hybrid 9. Domestic consumption of such QPM
grains will help in reducing protein malnutri-
tion in the hills and mountains. In view of this,
F
1
hybrid seeds of Vivek QPM 9 are being pro-
duced on a large scale for distribution in Uttarak-
hand and other parts of the country. A few vil-
lages in Uttarakhand have also been identified
for conversion to QPM villages. Vivek QPM 9
can potentially replace Vivek Hybrid 9 as well
as composites without any yield penalty in these
areas. The approach outlined above was also used
to develop QPM versions of several elite, early
maturing inbred lines adapted to the hill regions
of India (Gupta et al. 2009). QPM versions of
six elite inbred lines, which are the parents of
three single-cross hybrids
−
PEHM2, Parkash,
and PEEHM5
have been developed recently
by the Maize Genetics Unit, Indian Agricultural
Research Institute (IARI), New Delhi, through
the ICAR Network Project on Molecular Breed-
ing (Prasanna et al. 2010). A Network Project on
molecular breeding for QPM is also being imple-
mented in India, funded by the Department of
Biotechnology (DBT), Govt. of India, for con-
version of several important Indian maize inbred
lines into QPM versions.
−
QPMasanAnimalFeed
Another important use of QPM is as a less
expensive source of high protein animal feed
for monogastric animals, such as pigs and poul-
try. Unlike ruminant animals (i.e., cattle, sheep,
goats), monogastric animals require a more com-
plete protein than cereals alone can generally
provide. Conventional maize, insofar as it lacks
sufficient lysine and tryptophan, presents nutri-
tional protein limitations for monogastric ani-
mals. These amino acids are usually supple-
mented in animal feeds with soybeans, pulses, or
commercially produced synthetic amino acids.
QPM presents another option. Studies have doc-
umented improved growth in pigs and poultry
when QPM is substituted for conventional maize,
thereby
increasing
the
bioavailable
protein
(Sullivan et al. 1989).
Although using QPM in commercial feed
could possibly have a significant impact (Laud-
erdale
2000),
more
frequently,
the
poultry
industry
supplements
maize-based
feed
with
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